ASTM F3061/F3061M-23b

Standard Specification for Systems and Equipment in Aircraft

SCOPE
1.1 This specification covers the systems and equipment aspects of airworthiness and design for aircraft. The material was developed through open consensus of international experts in general aviation. This information was created by focusing on Level 1, 2, 3, and 4 Normal Category aeroplanes. The content may be more broadly applicable; it is the responsibility of the Applicant to substantiate broader applicability as a specific means of compliance. The topics covered within this specification are: Basic Information, Electrical Systems, Environmental Requirements, Manual Flight Controls, Automatic Flight Controls, Flight Data and Voice Recording, Hazard Mitigation, Hydraulic Systems, Instrumentation, Mechanical Systems and Equipment, Exterior Lighting, Oxygen Systems, Pneumatic Systems, Lightning Protection, and High-Intensity Radiated Field (HIRF) Protection.  
1.2 An applicant intending to propose this information as Means of Compliance for a design approval must seek guidance from their respective oversight authority (for example, published guidance from applicable civil aviation authorities (CAAs) concerning the acceptable use and application thereof. For information on which oversight authorities have accepted this standard (in whole or in part) as an acceptable Means of Compliance to their regulatory requirements (hereinafter “the Rules”), refer to the ASTM Committee F44 web page (www.astm.org/COMMITTEE/F44.htm).  
1.3 This document may present information in either SI units, English Engineering units, or both; the values stated in each system may not be exact equivalents. Each system shall be used independently of the other; combining values from the two systems may result in nonconformance with the standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Sep-2023
• ICS: 49.020 - Aircraft and space vehicles in general
• Technical Committee: F44 - General Aviation Aircraft
• Drafting Committee: F44.50 - Systems and Equipment

Relations

• Replaces: ASTM F3061/F3061M-23a - Standard Specification for Systems and Equipment in Aircraft
• Effective Date: 01-Oct-2023
• Refers: ASTM F3309/F3309M-24 - Standard Practice for Simplified Safety Assessment of Systems and Equipment in Small Aircraft
• Effective Date: 01-Mar-2024
• Refers: ASTM F3532-23 - Standard Practice for Protection of Aircraft Systems from Intentional Unauthorized Electronic Interactions
• Effective Date: 01-Nov-2023
• Refers: ASTM F3233/F3233M-23a - Standard Specification for Flight and Navigation Instrumentation in Aircraft
• Effective Date: 01-Nov-2023
• Refers: ASTM F3232/F3232M-23a - Standard Specification for Flight Controls in Small Aircraft
• Effective Date: 01-Oct-2023
• Refers: ASTM F3116/F3116M-23a - Standard Specification for Design Loads and Conditions
• Effective Date: 01-Oct-2023
• Refers: ASTM F3367-23 - Standard Practice for Simplified Methods for Addressing High-Intensity Radiated Fields (HIRF) and Indirect Effects of Lightning on Aircraft
• Effective Date: 01-Oct-2023
• Refers: ASTM F3179/F3179M-23 - Standard Specification for Performance of Aircraft
• Effective Date: 01-Sep-2023
• Refers: ASTM F3232/F3232M-23 - Standard Specification for Flight Controls in Small Aircraft
• Effective Date: 01-May-2023
• Refers: ASTM F3116/F3116M-23 - Standard Specification for Design Loads and Conditions
• Effective Date: 15-Mar-2023
• Refers: ASTM F3179/F3179M-22e1 - Standard Specification for Performance of Aircraft
• Effective Date: 01-Jan-2022
• Refers: ASTM F3367-21a - Standard Practice for Simplified Methods for Addressing High-Intensity Radiated Fields (HIRF) and Indirect Effects of Lightning on Aircraft
• Effective Date: 01-Nov-2021
• Referred By: ASTM F3227/F3227M-22 - Standard Specification for Environmental Systems in Aircraft
• Effective Date: 01-Oct-2023
• Referred By: ASTM F3229/F3229M-17(2023) - Standard Practice for Static Pressure System Tests in Small Aircraft
• Effective Date: 01-Oct-2023
• Referred By: ASTM F3231/F3231M-23 - Standard Specification for Electrical Systems for Aircraft with Combustion Engine Electrical Power Generation
• Effective Date: 01-Oct-2023

Overview

ASTM F3061/F3061M-23b: Standard Specification for Systems and Equipment in Aircraft is an international benchmark established by ASTM for airworthiness and design of aircraft systems and equipment. Developed by consensus among aviation experts, this specification provides comprehensive requirements applicable primarily to Level 1, 2, 3, and 4 Normal Category aeroplanes, with the possibility for broader use if appropriately substantiated. The standard covers the entire lifecycle of key aircraft systems, addressing safety, compliance, and performance, thereby supporting applicants and manufacturers aiming to meet airworthiness certification.

Key Topics

This ASTM aircraft systems standard encompasses a broad array of critical topics for airworthiness and compliance, including:

• Basic Information and Equipment Identification: Mandates appropriate function, installation, and marking of equipment.
• Electrical and Environmental Systems: Sets requirements for reliability, safety, and functional performance in both conventional and electric/hybrid aircraft.
• Manual and Automatic Flight Controls: Covers controls’ design, installation, and interaction, ensuring operational safety.
• Flight Data and Voice Recording: Specifies criteria for recording devices, supporting safety investigations.
• Hazard Mitigation: Details practices for fire protection, takeoff warning systems, hazard isolation, and high-energy rotor containment.
• Hydraulic and Pneumatic Systems: Addresses pressure, fluid management, and failure prevention.
• Instrumentation: Defines instrumentation requirements for accurate flight and systems information.
• Mechanical Systems and Equipment: Including landing gear requirements, performance testing, and shock absorption.
• Exterior Lighting and Oxygen Systems: Ensures compliance with operational and safety standards.
• Lightning and High-Intensity Radiated Field (HIRF) Protection: Mandates measures for electromagnetic interference resilience.
• Network Information Security: Requires risk assessments and mitigation of intentional unauthorized electronic interactions.
• Software and Airborne Electronic Hardware: Establishes development assurance processes and verification methods.

Applications

This aircraft systems specification is directly applicable to manufacturers, designers, and applicants seeking type certification of general aviation aircraft. Key practical uses include:

• Design Compliance: Providing a recognized structure to demonstrate system safety, reliability, and regulatory conformity.
• Means of Compliance Substantiation: Used by applicants to show that aircraft systems meet regulatory requirements, subject to approval by applicable civil aviation authorities.
• Risk Mitigation: Facilitating the identification, classification, and management of failure conditions, including fire hazards and system redundancy assessments.
• Cross-System Integration: Addressing potential interactions between varied systems-such as electrical, mechanical, or control systems-to prevent adverse effects on safety or performance.
• Updated Certification Approaches: Incorporates current methodologies for hardware, software, and network security, responding to evolving threats and technology trends.
• Global Standardization: Promotes uniformity and clarity in international type approval and safety assurance processes, reducing duplication and inconsistency.

Related Standards

ASTM F3061/F3061M-23b references and aligns with several essential industry standards, ensuring comprehensive coverage of aircraft systems. Key related standards include:

• ASTM F3060: Terminology for Aircraft
• ASTM F3083/F3083M: Specification for Emergency Conditions and Occupant Safety
• ASTM F3116/F3116M: Specification for Design Loads and Conditions
• ASTM F3117/F3117M: Specification for Crew Interface in Aircraft
• ASTM F3153: Specification for Verification of Aircraft Systems and Equipment
• ASTM F3173/F3173M: Aircraft Handling Characteristics
• ASTM F3179/F3179M: Performance of Aircraft
• ASTM F3227/F3227M / F3228: Environmental and Flight Data/Voice Recording in Small Aircraft
• ASTM F3230: Practice for Safety Assessment of Systems and Equipment
• ASTM F3231/F3231M / F3316/F3316M: Electrical Systems Specifications
• ASTM F3232/F3232M: Flight Controls in Small Aircraft
• F3233/F3233M: Instrumentation in Aircraft
• F3234/F3234M: Exterior Lighting
• F3236: High-Intensity Radiated Field (HIRF) Protection in Small Aircraft

Additional external references include SAE ARP4754 for system development, RTCA DO-178 and DO-254 for software/hardware assurance, and guidance from various Civil Aviation Authorities (CAAs).

Conclusion

ASTM F3061/F3061M-23b is an essential standard for the effective design, verification, and certification of aircraft systems and equipment, advancing safety, performance, and global consistency in general aviation. By following this standard, stakeholders benefit from clear compliance pathways, robust hazard mitigation, and up-to-date technological guidance, supporting safer skies worldwide.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F3061/F3061M − 23b
Standard Specification for
Systems and Equipment in Aircraft
This standard is issued under the fixed designation F3061/F3061M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
1.1 This specification covers the systems and equipment
ization established in the Decision on Principles for the
aspects of airworthiness and design for aircraft. The material
Development of International Standards, Guides and Recom-
was developed through open consensus of international experts
mendations issued by the World Trade Organization Technical
in general aviation. This information was created by focusing
Barriers to Trade (TBT) Committee.
on Level 1, 2, 3, and 4 Normal Category aeroplanes. The
content may be more broadly applicable; it is the responsibility
2. Referenced Documents
of the Applicant to substantiate broader applicability as a
2.1 Following is a list of external standards referenced
specific means of compliance. The topics covered within this
throughout this specification; the earliest revision acceptable
specification are: Basic Information, Electrical Systems, Envi-
for use is indicated. In all cases later document revisions are
ronmental Requirements, Manual Flight Controls, Automatic
acceptable if shown to be equivalent to the listed revision, or if
Flight Controls, Flight Data and Voice Recording, Hazard
otherwise formally accepted by the governing civil aviation
Mitigation, Hydraulic Systems, Instrumentation, Mechanical
authority; earlier revisions are not acceptable.
Systems and Equipment, Exterior Lighting, Oxygen Systems,
Pneumatic Systems, Lightning Protection, and High-Intensity
2.2 ASTM Standards:
Radiated Field (HIRF) Protection.
F3060 Terminology for Aircraft
F3083/F3083M Specification for Emergency Conditions,
1.2 An applicant intending to propose this information as
Occupant Safety and Accommodations
Means of Compliance for a design approval must seek guid-
F3116/F3116M Specification for Design Loads and Condi-
ance from their respective oversight authority (for example,
tions
published guidance from applicable civil aviation authorities
F3117/F3117M Specification for Crew Interface in Aircraft
(CAAs) concerning the acceptable use and application thereof.
F3153 Specification for Verification of Aircraft Systems and
For information on which oversight authorities have accepted
Equipment
this standard (in whole or in part) as an acceptable Means of
F3173/F3173M Specification for Aircraft Handling Charac-
Compliance to their regulatory requirements (hereinafter “the
teristics
Rules”), refer to the ASTM Committee F44 web page
F3179/F3179M Specification for Performance of Aircraft
(www.astm.org/COMMITTEE/F44.htm).
F3227/F3227M Specification for Environmental Systems in
1.3 This document may present information in either SI
Aircraft
units, English Engineering units, or both; the values stated in
F3228 Specification for Flight Data and Voice Recording in
each system may not be exact equivalents. Each system shall
Small Aircraft
be used independently of the other; combining values from the
F3230 Practice for Safety Assessment of Systems and
two systems may result in nonconformance with the standard.
Equipment in Small Aircraft
1.4 This standard does not purport to address all of the
F3231/F3231M Specification for Electrical Systems for Air-
safety concerns, if any, associated with its use. It is the
craft with Combustion Engine Electrical Power Genera-
responsibility of the user of this standard to establish appro-
tion
priate safety, health, and environmental practices and deter-
F3232/F3232M Specification for Flight Controls in Small
mine the applicability of regulatory limitations prior to use.
Aircraft
F3233/F3233M Specification for Flight and Navigation In-
strumentation in Aircraft
This specification is under the jurisdiction of ASTM Committee F44 on General
Aviation Aircraft and is the direct responsibility of Subcommittee F44.50 on
Systems and Equipment. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved Oct. 1, 2023. Published November 2023. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 2015. Last previous edition approved in 2023 as F3061/F3061M–23a. Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/F3061_F3061M-23B. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F3061/F3061M − 23b
F3234/F3234M Specification for Exterior Lighting in Small intention to permit access or to enter/exit. The movable barrier
Aircraft must be opened and closed without the use of tools to operate.
F3236 Specification for High Intensity Radiated Field
3.2.4 development assurance level, n—a development assur-
(HIRF) Protection in Small Aircraft
ance level is an indication of the level of those planned and
F3309/F3309M Practice for Simplified Safety Assessment of
systematic actions used to substantiate, to an adequate level of
Systems and Equipment in Small Aircraft
confidence, that errors in requirements, design, and implemen-
F3316/F3316M Specification for Electrical Systems for Air-
tation have been identified and corrected such that the system
craft with Electric or Hybrid-Electric Propulsion
satisfies the applicable certification basis.
F3367 Practice for Simplified Methods for Addressing High-
3.2.5 latched, adj—in door systems (reference 13.12),
Intensity Radiated Fields (HIRF) and Indirect Effects of
means the latches are fully engaged with their structural
Lightning on Aircraft
counterparts and held in position by the latch operating
F3532 Practice for Protection of Aircraft Systems from
mechanism.
Intentional Unauthorized Electronic Interactions
3.2.6 latches, n—in door systems (reference 13.12), mov-
2.3 SAE Standard:
able mechanical elements that, when engaged, prevent the door
SAE ARP4754, Rev A Guidelines for Development of Civil
from opening.
Aircraft Systems
3.2.7 locked, adj—in door systems (reference 13.12), means
2.4 Other Standards:
the locks are fully engaged.
AC/AMC 20-136 Protection of Aircraft Electrical/Electronic
Systems against the Indirect Effects of Lightning
3.2.8 locks, n—in door systems (reference 13.12), mechani-
FAA-S-8081-14B, Change 5 Private Pilot Practical Test
cal elements, in addition to the latch operating mechanism, that
Standards for Airplane
monitor the latch positions and, when engaged, prevent latches
RTCA DO-178, Rev B Software Considerations in Airborne
from becoming disengaged.
Systems and Equipment Certification
3.2.9 pneumatic system elements, n—components associ-
RTCA DO-254 Design Assurance Guidance for Airborne
5 ated with systems that use bleed air or other sources of
Electronic Hardware
compressed gas for their function (ice protection, vapor cycle
cooling, rudder bias, door seal inflation, brake heating, emer-
3. Terminology
gency gear extension, emergency braking, etc.) Within the
3.1 Terminology specific to this standard is provided below.
context of pressurization systems, pneumatic system elements
For general terminology, refer to Terminology F3060.
include the valve(s) that regulates cabin inflow as well as all
3.2 Definitions of Terms Specific to This Standard: upstream equipment items that utilize bleed air; refer to 3.2.10.
3.2.1 closed, adj—in door systems (reference 13.12), means
3.2.10 pressurization system elements, n—components
the door has been placed within the doorframe in such a
downstream of the valve(s) that regulates cabin inflow; refer to
position that the latches can be operated to the “latched”
3.2.9.
condition. Fully closed means the door is placed within the
3.2.11 primary function, n—a primary function is a function
doorframe in the position it will occupy when the latches are in
that is installed to comply with applicable requirements for a
the latched condition.
required function and that provides the most pertinent controls
3.2.2 continued safe flight and landing, n—continued safe
or information instantly and directly to the pilot.
flight and landing is defined as the capability for continued
3.2.12 primary system, n—a primary system is a system that
controlled flight and landing, possibly using emergency
provides a primary function.
procedures, but without requiring pilot skill beyond that
needed to pass the Private Pilot Practical Test Standard for
3.2.13 secondary system, n—a secondary system is a redun-
Airplane (refer to FAA-S-8081-14B), or requiring pilot forces
dancy system that provides the same function as the primary
beyond those defined in Specification F3173/F3173M. Landing
system.
may occur either at an airport or at an emergency landing
3.2.14 unsafe system operating condition, n—an unsafe
location consistent with established emergency procedures.
system operating condition is any system operating condition
Some aircraft damage may be realized, either during flight or
which, if not detected and properly accommodated by crew
upon landing.
action, would cause one or more serious injuries.
3.2.3 door, n—in door systems (reference 13.12), a movable
barrier that is located on the exterior of the fuselage or in the
4. Basic Information
primary pressure vessel on a pressurized aircraft with the
NOTE 1—The requirements of this chapter are applicable to all systems
and equipment installed in the aircraft. These requirements are in addition
to and do not supersede any additional system specific requirements
identified elsewhere in these design standards or contained in the rules of
Available from SAE International (SAE), 400 Commonwealth Dr., Warrendale,
the governing civil aviation authority.
PA 15096, http://www.sae.org.
Available from Federal Aviation Administration (FAA), 800 Independence
4.1 Function and Installation:
Ave., SW, Washington, DC 20591, http://www.faa.gov.
4.1.1 Each item of installed equipment must be of a kind
Available from RTCA, 1150 18th NW, Suite 910, Washington, DC 20036,
https://www.rtca.org. and design appropriate to its intended function.
F3061/F3061M − 23b
4.1.2 Each item of installed equipment must be marked in a
Level 1 and Low-Stall All Others
and Day-VFR
way that makes it clear to an installer the equipment’s
Reserved The aircraft systems and associated components,
identification, function, or operating limitations, or any appli-
considered separately and in relation to other systems,
cable combination of these factors. It is acceptable to reference must be designed and installed so that each
Catastrophic Failure Condition is “extremely
equipment installation manuals for function or limitation
improbable.”
information.
4.2.2.2
4.1.3 Each item of installed equipment must be installed
Level 1 and Low-Stall All Others
according to limitations specified for that equipment.
and Day-VFR
4.1.4 Each item of installed equipment must function prop-
Reserved The aircraft systems and associated components,
erly when installed.
considered separately and in relation to other systems,
must be designed and installed so that each
4.1.5 The aircraft systems and equipment required for type
Hazardous Failure Condition is “extremely remote.”
certification or by operating rules must be designed and
4.2.2.3
installed so that they perform as intended under the aircraft
Level 1 and Low-Stall All Others
operating and environmental conditions.
and Day-VFR
Reserved The aircraft systems and associated components,
NOTE 2—The intent of this requirement is to provide assurance that the
considered separately and in relation to other systems,
required systems and equipment will function as intended in the expected
must be designed and installed so that each Major
operating and environmental conditions. It is recognized that random
Failure Condition is “remote.”
failures will occur throughout the aircraft life and that the failed device
may no longer “perform as intended.” The acceptability of such failures or
combination of failures and their associated risks are addressed under the
requirements of 4.2.
4.1.6
Level 1 and Low-Stall All Others
and Day-VFR
Reserved All aircraft systems and equipment must be designed
and installed so that they do not adversely affect the
safety of the aircraft or its occupants.
4.1.7 All aircraft systems and equipment must be designed
and installed so that they do not adversely affect the proper
functioning of those systems or equipment, or both, covered by
4.1.5.
4.1.8 Those systems and equipment not required for type
certification or by operating rules are not required to perform
their intended function under all aircraft operating and envi-
ronmental conditions, provided that the resultant failure con-
ditions are classified as “Negligible Failure Condition” in the
assessment conducted per 4.2.1; refer to Practice F3230.
4.1.8.1 Non-required systems and equipment with failure
conditions classified more severe than “Negligible Failure
Condition” are not required to perform their intended function
under all aircraft operating and environmental conditions,
provided the failure is appropriately annunciated to the crew.
4.1.8.2 When addressing the requirements of 4.2, if any
credit is taken for the installation, or any aspect, of these
non-required systems, the portion of the system for which
credit is taken must comply with 4.1.4.
4.2 System Safety Requirements:
4.2.1 An assessment of the aircraft and system functions
must be performed to identify and classify the various Failure
Conditions associated with each function.
4.2.1.1 Practice F3230 provides one method of satisfying
4.2 for all normal category aircraft.
4.2.1.2 Practice F3309/F3309M provides one method of
satisfying 4.2 for a limited set of aircraft as defined in that
practice.
4.2.2 The equipment, systems, and installations must be
designed to minimize hazards to the aircraft in the event of a
probable malfunction or failure.
4.2.2.1
F3061/F3061M − 23b
to jet aircraft with high takeoff and landing speeds.
4.2.2.4
Level 1 and Low-Stall All Others 4.2.4
and Day-VFR
Level 1 and Low-Stall All Others
Reserved For definitions of the failure condition severities and
and Day-VFR
the qualitative probability terms used in 4.2.2, refer to
Reserved Based on the results of the assessment per 4.2.1, the
Practice F3230.
depth of analysis required to show compliance may be
determined in accordance with Practice F3230 or
4.2.3 As used in 4.2, the term “systems” refers to all
Practice F3309/F3309M.
pneumatic systems, fluid systems, electrical systems, mechani-
4.2.5 Reserved
cal systems, and powerplant systems included in the aircraft
4.2.6
design except as provided in 4.2.3.1 – 4.2.3.3.
Level 1 and Low-Stall All Others
4.2.3.1 Powerplant systems provided as part of the type-
and Day-VFR
certified engine are not subject to the provisions of 4.2.
Reserved Information concerning an unsafe system operating
4.2.3.2 The flight structure (such as wing, fuselage, condition must be provided in a timely manner to the
crew to enable them to take appropriate corrective
empennage, engine-mounting, control surfaces and their asso-
action; refer to 3.2.14.
ciated simple systems, and landing gear and their primary
4.2.6.1
attachments) are not subject to the provisions of 4.2.
Level 1 and Low-Stall All Others
4.2.3.3 Single failures within brake systems, including as-
and Day-VFR
sociated systems and components, are not subject to the
Reserved In showing compliance with the provisions of 4.2.6, if
immediate pilot awareness and immediate or
provisions of 4.2 provided it is shown that the aircraft can be
subsequent corrective action is required, the
brought to rest, with a braked-roll stopping distance of not
information required by 4.2.6 must be presented in
more than two times that obtained in determining the landing
accordance with Specification F3117/F3117M.
distance per Specification F3179/F3179M, following:
4.2.6.2
(1) Failure of any electrical, pneumatic, hydraulic, or
Level 1 and Low-Stall All Others
mechanical connecting or transmitting element; or
and Day-VFR
(2) Loss of any single source of hydraulic or other brake- Reserved In showing compliance with the provisions of 4.2.6,
one method of assessing an unsafe system operating
operating energy.
condition is presented in Appendix X2.
NOTE 3—The allowances of 4.2.3.3 have traditionally been applied only
F3061/F3061M − 23b
4.3 Systems and Equipment, Network Information Security in accordance with the Development Assurance Level assign-
Protection: ment methodology outlined in SAE ARP4754; refer to 3.2.4.
4.3.1 4.4.1.1 Once a DAL has been assigned, RTCA DO-178
provides an acceptable means to satisfy the requirements of
Level 1 and Low-Stall All Others
and Day-VFR
4.4.1 for software and DO-254 provides an acceptable means
Reserved Connectivity of aircraft systems to external networks or
to satisfy 4.4.1 for AEH; refer to Section 2.
devices can lead to an increased risk of intentional
unauthorized electronic interactions (IUEI). Aircraft 4.4.2 System Level Verification—Software and airborne
systems and equipment must have mitigations to
electronic hardware within systems and equipment installed in
protect against failure conditions that could result from
certification level 1 and 2 normal category aircraft may be
IUEI.
approved using system level verification.
4.3.2 When aircraft systems are connected to external net-
4.4.2.1 Specification F3153 provides an acceptable method
works or devices, a security assessment must be performed
to meet the requirements of 4.4.2; Refer to Section 2.
that:
4.3.2.1
NOTE 4—The acceptability of this method varies between regulatory
agencies. It is generally not considered an acceptable approach for
Level 1 and Low-Stall All Others
and Day-VFR complex, novel systems such as fly-by-wire or propulsion systems. The
Reserved Identifies any security risks that could lead to abnormal
applicant must seek individual guidance from their respective CAA
system operation that would be considered a failure
concerning the use of system level verification.
condition;
4.3.2.2
5. Electrical Systems
Level 1 and Low-Stall All Others
5.1 Electrical System Requirements—In addition to the
and Day-VFR
Reserved Demonstrates that adequate mitigations have been applicable requirements of this specification, electrical systems
provided to prevent the failure condition from
shall comply with the provisions of 5.1.1 and 5.1.2.
occurring. The mitigations must be shown to be
5.1.1 Electrical systems for aircraft equipped with
appropriate for the severity of failure condition that
they protect against.
combustion-engine propulsion shall comply with the provi-
4.3.3 Practice F3532 is an acceptable method of meeting sions of Specification F3231/F3231M.
4.3.1 and 4.3.2.
5.1.2 Electrical systems for aircraft equipped with electric
propulsion shall comply with the provisions of Specification
4.4 Software and Airborne Electronic Hardware:
F3316/F3316M.
Level 1 and All other Level 1 and level 2 All Others
Low-Stall and
Day-VFR
6. Environmental Requirements
Reserved Software and airborne Software and airborne
electronic hardware can be electronic hardware must be
6.1 Ventilation Requirements—In addition to the applicable
addressed via development addressed via development
requirements of this specification, ventilation systems shall
assurance in accordance with assurance in accordance with
comply with the corresponding provisions of Specification
4.4.1 4.4.1.
Or
F3227/F3227M.
Via System level verification in
accordance with 4.4.2.
6.2 Pressurization Requirements—In addition to the appli-
4.4.1 Development Assurance—Software and Airborne cable requirements of this specification, pressurization systems
Electronic Hardware must be designed with the appropriate shall comply with the corresponding provisions of Specifica-
Development Assurance Level (DAL) as specified in Table 1 or tion F3227/F3227M.
TABLE 1 Development Assurance Level Requirements
A
Classification of Failure Conditions
Negligible Minor Major Hazardous Catastrophic
A
Assessment Level
Software (SW) and Airborne Electronic Hardware (AEH)
B
Development Assurance Levels (DALs)
I P=D P=C, S=D P=C, S=D P=C, S=C
C C C
(See ) (See ) (See )
II No SW P=D P=C, S=D P=C, S=C P=C, S=C
C C C
and/or (See ) (See ) (See )
III HW DAL P=D P=C, S=D P=C, S=C P=B, S=C
C C C
Requirement (See ) (See ) (See )
IV P=D P=C, S=D P=B, S=C P=A, S=B
C C C
(See ) (See ) (See )
A
Refer to Practice F3230.
B
The letters of the alphabet used above denote the typical SW and AEH DALs. “P” indicates the primary system; “S” indicates the secondary system; “A,” “B,” “C,” and
“D” indicate the DAL in accordance with RTCA DO-178 or RTCA DO-254 as applicable. For example, an indication of “P=A” would translate to a SW or AEH DAL of “A”
on the primary system.
C
A secondary system is not necessarily required; however, if a secondary system is needed to meet the probability goals of Practice F3230, then that secondary system
must meet the stated DAL goal.
F3061/F3061M − 23b
7. Manual Flight Controls generated by a line passing through the center of the propeller
hub making an angle of 5° forward or aft of the plane of
7.1 Manual Flight Control Requirements—In addition to the
rotation of the propeller.
applicable requirements of this specification, manual flight
controls shall comply with the corresponding provisions of 10.3 Flammable Fluid Fire Protection:
Specification F3232/F3232M. 10.3.1 Lines, tanks, or equipment containing fuel, oil, or
other flammable fluids may not be installed in compartments to
8. Automatic Flight Controls
be used by the crew or passengers unless adequately shielded,
isolated, or otherwise protected so that any breakage or failure
8.1 Automatic Flight Control Requirements—In addition to
of such an item would not create a hazard.
the applicable requirements of this specification, automatic
10.3.2 In each area where flammable fluids or vapors might
flight controls shall comply with the corresponding provisions
escape by leakage of a fluid system, there must be means to
of Specification F3232/F3232M.
minimize the probability of ignition of the fluids and vapors,
and the resultant hazard if ignition does occur; compliance
9. Flight Data and Voice Recording
must be shown by analysis or test.
9.1 Flight Recorder Requirements—In addition to the appli-
10.3.3
cable requirements of this specification, flight data and voice
Level 1 All Others
recording installations shall comply with the provisions of
Reserved Possible sources and paths of fluid leakage, and
Specification F3228.
means of detecting leakage, must be considered when
showing compliance with 10.3.2.
10. Hazard Mitigation
10.3.4
10.1 Takeoff Warning System:
Level 1 All Others
Reserved Flammability characteristics of fluids, including effects
Level 1 All Others
of any combustible or absorbing materials, must be
Reserved Unless it can be shown that a lift or longitudinal trim
considered when showing compliance with 10.3.2.
device that affects the takeoff performance of the
aircraft would not give an unsafe takeoff configuration
10.3.5
when selected out of an approved takeoff position, a
Level 1 All Others
takeoff warning system must be installed and meet the
Reserved Possible ignition sources, including electrical faults,
requirements of 10.1.1 – 10.1.4.
overheating of equipment, and malfunctioning of
10.1.1
protective devices, must be considered when showing
compliance with 10.3.2.
Level 1 All Others
Reserved In showing compliance with 10.1, the system must
10.3.6
provide to the pilots an aural warning that is
Level 1 All Others
automatically activated during the initial portion of the
Reserved Means available for controlling or extinguishing a fire,
takeoff roll if the aircraft is in a configuration that would
such as stopping flow of fluids, shutting down
not allow a safe takeoff.
equipment, fireproof containment, or use of
10.1.2
extinguishing agents, must be considered when
showing compliance with 10.3.2.
Level 1 All Others
Reserved The warning provided in accordance with 10.1.1 must
10.3.7
continue until the configuration is changed to allow
Level 1 All Others
safe takeoff, or action is taken by the pilot to abandon
Reserved Ability of aircraft components that are critical to safety
the takeoff roll.
of flight to withstand fire and heat must be considered
10.1.3
when showing compliance with 10.3.2.
Level 1 All Others
10.3.8
Reserved In showing compliance with 10.1, the means used to
Level 1 All Others
activate the system must function properly for all
Reserved If action by the flight crew is required to prevent or
authorized takeoff power settings and procedures and
counteract a fluid fire (for example, equipment
throughout the ranges of takeoff weights, altitudes, and
shutdown or actuation of a fire extinguisher), quick
temperatures for which certification is requested.
acting means must be provided to alert the crew.
10.1.4
10.3.9
Level 1 All Others
Level 1 All Others
Reserved For the purpose of showing compliance with 10.1, an
Reserved Each area where flammable fluids or vapors might
unsafe takeoff configuration is the inability to rotate or
escape by leakage of a fluid system must be identified
the inability to prevent an immediate stall after rotation.
and defined.
This section is not intended to apply to control locks;
refer to Specification F3232/F3232M.
10.4 Fire Protection of Cargo and Baggage Compartments:
10.4.1 Sources of heat within each cargo and baggage
.
compartment that are capable of igniting the compartment
10.2 Pilot Compartment—For each pilot compartment, the
contents must be shielded and insulated to prevent such
pilot and the aerodynamic controls listed in Specification
ignition.
F3117/F3117M, excluding cables and control rods, must be
suitably protected from items of mass departing a propeller.
10.2.1 The provisions of 10.2 may be met by ensuring that
no part of the pilot or the controls lies in the region between the
plane of rotation of any inboard propeller and the surface
F3061/F3061M − 23b
10.4.2 10.7.4
Level 4 All Others Single Engine All Others
If the requirements of either 10.4.3 or 10.4.4 are not Reserved Reserved Each shutoff must be outside of the engine
met, each cargo and baggage compartment must be compartment unless an equal degree of safety is
located where the presence of a fire would be easily provided with the shutoff inside the compartment.
discovered by the pilots when seated at their duty
10.7.5
station, or it must be equipped with a smoke or fire
detector system to give a warning at the pilots’ station,
Single Engine All Others
and provide sufficient access to enable a pilot to
Reserved Not more than 0.95 L [0.25 US gal] of flammable fluid
effectively reach any part of the compartment with the
may escape into the engine compartment after engine
contents of a hand held fire extinguisher.
shutoff. For those installations where the flammable
fluid that escapes after shutdown cannot be limited to
10.4.3
0.95 L [0.25 US gal], it must be demonstrated that this
Level 4 All Others
greater amount can be safely contained or drained
If the requirements of either 10.4.2 or 10.4.4 are not Reserved
overboard.
met, each cargo and baggage compartment must be
10.7.6
equipped with a smoke or fire detector system to give
a warning at the pilots’ station. In addition, each
Single Engine All Others
compartment must meet the requirements of
Reserved There must be means to guard against inadvertent
Specification F3083/F3083M.
operations of each shutoff means, and to make it
possible for the crew to reopen the shutoff means in
10.4.4
flight after it has been closed.
Level 4 All Others
10.7.7
If the requirements of either 10.4.2 or 10.4.3 are not Reserved
met, each cargo and baggage compartment must be
Reciprocating Engine Turbine Engine Aircraft
constructed and sealed to contain any fire within the
Aircraft
compartment.
Reserved Engine installations need not have an engine oil
system shutoff if the conditions of 10.7.7.1 and
10.5 Fire Protection of Flight Controls—Flight controls
10.7.7.2 are met.
located in designated fire zones, or in adjacent areas that would
10.7.7.1
be subjected to the effects of fire in the designated fire zones,
must be constructed of fireproof material or be shielded so that Reciprocating Engine Turbine Engine Aircraft
Aircraft
they are capable of withstanding the effects of a fire.
Reserved To comply with 10.7.7, the oil tank must be integral
with, or mounted on, the engine.
10.6 Lines, Fittings, and Components:
10.6.1 Except as provided in 10.6.3 and 10.6.4,
10.7.7.2
components, lines, and fittings must be shielded or located so
Reciprocating Engine Turbine Engine Aircraft
as to safeguard against the ignition of leaking flammable fluid.
Aircraft
Reserved To comply with 10.7.7, all oil system components
10.6.2 Except as provided in 10.6.3 and 10.6.4, flexible hose
external to the engine must be fireproof or located in
assemblies (hose and end fittings) must be shown to be suitable
areas not subject to engine fire conditions.
for the particular application.
10.7.8 Power operated shut off valves must have means to
10.6.3 Subsections 10.6.1 and 10.6.2 do not apply to lines,
indicate to the flight crew when the valve has reached the
fittings, and components, which are already approved as part of
selected position and must be designed so that the valve will
the type certificated engine.
not move from the selected position under vibration conditions
10.6.4 Subsections 10.6.1 and 10.6.2 do not apply to vent
likely to exist at the valve location.
and drain lines, and their fittings, whose failure will not result
in, or add to, a fire hazard. 10.8
Single Engine All Others
10.7 Shutoff Means:
Reserved Engine-driven accessories essential to safe operation
10.7.1
must be distributed among two or more engines so
that the failure of any one engine will not impair safe
Single Engine All Others
operation through the malfunctioning of these
Reserved Each engine installation must have means to shut off
accessories.
or otherwise prevent hazardous quantities of
flammable liquids from flowing into, within, or through
10.9 Equipment Containing High Energy Rotors:
any engine compartment, except in lines, fittings, and
components forming an integral part of an engine. 10.9.1 High energy rotors contained in equipment such as
Auxiliary Power Units (APUs) and constant speed drive units
10.7.2
must be able to withstand damage caused by malfunctions,
Single Engine All Others
vibration, abnormal speeds, and abnormal temperatures.
Reserved The closing of the fuel shutoff valve for any engine
may not make any fuel unavailable to the remaining
10.9.2 Auxiliary rotor cases in equipment such as Auxiliary
engines that would be available to those engines with
Power Units (APUs) and constant speed drive units must be
that valve open.
able to contain damage caused by the failure of high energy
10.7.3
rotor blades.
Single Engine All Others
10.9.3 Equipment control devices, systems, and instrumen-
Reserved Operation of any shutoff means may not interfere with
tation must reasonably ensure that no operating limitations
the later emergency operation of other equipment such
as propeller feathering devices.
affecting the integrity of high energy rotors in equipment such
as Auxiliary Power Units (APUs) and constant speed drive
units will be exceeded in service.
F3061/F3061M − 23b
10.9.4 As an alternative to 10.9.1 – 10.9.3, it may be shown 13.1.1
by test that equipment containing high energy rotors can
Level 4 All Others
The main landing gear system must be designed so Reserved
contain any failure of a high energy rotor that occurs at the
that if it fails due to overloads during takeoff and
highest speed obtainable with the normal speed control devices
landing (assuming the overloads to act in the upward
inoperative.
and aft directions), the failure mode is not likely to
cause the spillage of enough fuel from any part of the
10.9.5 As an alternative to 10.9.1 – 10.9.4, equipment
fuel system to constitute a fire hazard.
containing high energy rotors may be located where rotor
13.1.2
failure will neither endanger the occupants nor adversely affect
continued safe flight. Level 4 All Others
Compliance with the provisions of 13.1.1 may be Reserved
shown by analysis or tests, or both.
11. Hydraulic Systems
13.2 Shock Absorption Tests:
11.1 Hydraulic Systems:
13.2.1 Except as provided in 13.2.1.1 – 13.2.1.3, it must be
11.1.1 Each hydraulic system and its elements must
shown by energy absorption tests that the limit load factors
withstand, without yielding, the structural loads expected in
selected for design in accordance with Specification F3116/
addition to hydraulic loads.
F3116M for takeoff and landing weights will not be exceeded.
11.1.2 A means to verify the quantity of hydraulic fluid in
13.2.1.1 For increases in previously approved takeoff or
the system must be provided.
landing weights, or both, the requirements of 13.2.1 may be
11.1.3 A means to indicate the pressure in each hydraulic
shown by analysis based on tests conducted on a landing gear
system which supplies two or more primary functions must be
system with identical energy absorption characteristics.
provided to the flight crew.
13.2.1.2
11.1.4 There must be means to ensure that the pressure,
Level 1 and Low-Stall All Others
including transient (surge) pressure, in any part of the system
The requirements of 13.2.1 may be shown by analysis Reserved
will not exceed the safe limit above design operating pressure.
based on previously approved wheel-type landing gear
11.1.5 There must be means to prevent excessive pressure
on aircraft with similar weights and performance.
resulting from fluid volumetric changes in all lines which are
13.2.1.3
likely to remain closed long enough for such changes to occur.
Level 1 and Low-Stall All Others
11.1.6 The minimum design burst pressure must be 2.5
The requirements of 13.2.1 may be shown by analysis Reserved
times the operating pressure. based on landing gear for which adequate experience
and substantiating data are available.
11.1.7 Each system must be substantiated by proof pressure
tests. 13.2.2 The landing gear may not fail, but may yield, in a test
11.1.7.1 When proof tested, no part of any system may fail, showing its reserve energy absorption capacity, simulating a
malfunction, or experience a permanent set. descent velocity of 1.2 times the limit descent velocity,
11.1.7.2 The proof load of each system must be at least 1.5 assuming wing lift equal to the weight of the aeroplane.
times the maximum operating pressure of that system.
13.3 Limit Drop Tests:
11.1.8 A hydraulic accumulator or reservoir may be in-
13.3.1 If compliance with 13.2.1 is shown by free drop tests,
stalled on the engine side of any firewall if: it is an integral part
these tests must be made on the complete aeroplane, or on units
of an engine or propeller system; or, the reservoir is nonpres-
consisting of wheel, tire, and shock absorber, in their proper
surized and the total capacity of all such nonpressurized
relation, from free drop heights not less than those determined
reservoirs is 0.95 L [0.25 US gal] or less.
by the following formula in conjunction with Table 2:
1⁄2
12. Instrumentation
W
h 5 C· (1)
S D
S
12.1 Instrumentation Requirements—In addition to the ap-
plicable requirements of this specification, instrumentation
13.3.1.1 In complying with the requirements of 13.3.1, the
shall comply with the provisions of Specification F3233/
free drop height may not be less than 0.234 m [9.2 in.] and
F3233M.
need not be more than 0.475 m [18.7 in.].
13.3.2 If the effect of wing lift is provided for in free drop
13. Mechanical Systems & Equipment
tests, the landing gear must be dropped with an effective
13.1 Landing Gear:
weight equal to that derived from the following formula in
conjunction with Table 3:
h1 d · 1 2 L
@ ~ !#
W 5 W· (2)
S D
e
h1d
TABLE 2 Legend for Drop Test Height Formula
Variable Value SI Units English Units
h Height of Free Drop Test m in.
C Unit Correction Factor 0.0414 3.6
W Design Maximum Takeoff Weight kg lb
m
2 2
S Wing Area (including fuselage projection) m ft
F3061/F3061M − 23b
TABLE 3 Legend for Effective Weight Formula
Variable Value SI Units English Units
W Effective Weight to be used in Drop Test kg lb
e m
h Specified Drop Height m in.
d Deflection Under Impact of the Tire at the Approved Inflation Pressure
PLUS m in.
Vertical Component of Axle Travel relative to the Drop Mass
For Main Gear Units, W
M
(Static Weight on that Unit with the Aircraft in Level Attitude, with the Nose
Wheel clear for nose-wheel type aircraft)
For Tail Gear Units, W
T
W (Static Weight on the Tail Unit with the Aircraft in the Tail-Down Attitude) kg lb
m
For Nose Wheel Units, W
N
(Vertical Component of the Static Reaction at the Nose Wheel, assuming that
the Mass of the Aircraft acts at the Center of Gravity and exerts a force of 1.0 g
Downward and 0.33 g Forward)
A
L Ratio of Assumed Wing Lift to Aircraft Weight — —
A
L need not be more than 0.667.
13.3.3 The limit inertia load factor must be determined in a 13.4.2 The critical landing condition for each of the design
rational or conservative manner, during the drop test, using a conditions specified in Specification F3116/F3116M must be
landing gear unit attitude, and applied drag loads, that represent used for proof strength.
the landing conditions.
13.5 Reserve Energy Absorption Drop Tests:
13.3.4 The value of d used in the computation of W in
e
13.5.1 If compliance with the reserve energy absorption
13.3.2 may not exceed the value actually obtained in the drop
requirements in 13.2.2 is shown by free drop tests, the drop
test.
height may not be less than 1.44 times that specified in 13.3.
13.3.5 The limit inertia load factor must be determined from
13.5.2 If the effect of wing lift is provided for, the units must
the drop test in 13.3.2 according to the following formula in
be dropped with an effective weight equal to that derived from
conjunction with Table 4:
the following formula in conjunction with Table 5:
n ·W
j e
h
n 5 1L (3)
W W 5 W· (4)
S D
e
h1d
13.3.6 The value of n determined in accordance with 13.3.5
13.6 Landing Gear Extension / Retraction Systems:
may not be more than the limit inertia load factor used in the
13.6.1 For aircraft with retractable landing gear, each land-
landing conditions in Specification F3116/F3116M.
ing gear retracting mechanism and its supporting structure
must be designed for maximum flight load factors with the gear
13.4 Ground Load Dynamic Tests:
13.4.1 If compliance with the ground load requirements of retracted.
Specification F3116/F3116M is shown dynamically by drop 13.6.2 For aircraft with retractable landing gear, each land-
test, one drop test must be conducted that meets the require- ing gear retracting mechanism and its supporting structure
ments of 13.3 except that the drop height must be either: 2.25 must be designed for the combination of friction, inertia, brake
times the drop height prescribed in 13.3.1; or, sufficient to torque, and air loads, occurring during retraction at any
develop 1.5 times the limit load factor. airspeed up to 1.6 times V with flaps retracted.
S1
TABLE 4 Legend for Limit Inertia Load Factor Formula
Variable Value SI Units English Units
n Limit Inertia Load Factor — —
n Acceleration (dv/dt, in g’s) as recorded in the Drop Test
j
PLUS — —
1.0
W Effective Weight to be used in Drop Test kg lb
e m
For Main Gear Units, W
M
(Static Weight on that Unit with the Aircraft in Level Attitude, with the Nose
Wheel clear for nose-wheel type aircraft)
For Tail Gear Units, W
T
W (Static Weight on the Tail Unit with the Aircraft in the Tail-Down Attitude) kg lb
m
For Nose Wheel Units, W
N
(Vertical Component of the Static Reaction at the Nose Wheel, assuming that
the Mass of the Aircraft acts at the Center of Gravity and exerts a force of 1.0 g
Downward and 0.33 g Forward)
A
L Ratio of Assumed Wing Lift to Aircraft Weight — —
A
L need not be more than 0.667.
F3061/F3061M − 23b
TABLE 5 Legend for Reserve Energy Effective Weight Formula
Variable Value SI Units English Units
W Effective Weight to be used in Drop Test kg lb
e m
h Specified Drop Height m in
d Deflection Under Impact of the Tire at the Approved Inflation Pressure
PLUS m in
Vertical Component of Axle Travel relative to the Drop Mass
For Main Gear Units, W
M
(Static Weight on that Unit with the Aircraft in Level Attitude, with the Nose
Wheel clear for nose-wheel type aircraft)
For Tail Gear Units, W
T
W (Static Weight on the Tail Unit with the Aircraft in the Tail-Down Attitude) kg lb
m
For Nose Wheel Units, W
N
(Vertical Component of the Static Reaction at the Nose Wheel, assuming that
the Mass of the Aircraft acts at the Center of Gravity and exerts a force of 1.0 g
Downward and 0.33 g Forward)
13.6.3 For aircraft with retractable landing gear, each land- 13.6.9.3 If there is a manual shutoff for the warning device
ing gear retracting mechanism and its supporting structure used to satisfy 13.6.9.1, the warning system must be designed
must be designed for any load factor up to those specified in so that when the warning has been suspended after one or more
Specification F3116/F3116M for the flaps-extended condition. throttles are closed, subsequent retardation of any throttle to, or
13.6.4 For aircraft with retractable landing gear, the landing beyond, the position for normal landing approach will activate
gear and retracting mechanism, including the wheel well doors, the warning device.
must withstand flight loads, including loads resulting from all 13.6.9.4 At least one warning device must function continu-
yawing conditions specified in Specification F3116/F3116M,
ously when the wing flaps are extended beyond the maximum
with the landing gear extended at any speed up to at least 1.6 approach flap position, using a normal landing procedure, if the
times V with the flaps retracted.
landing gear is not fully extended and locked.
S1
13.6.5 For aircraft with retractable landing gear, there must 13.6.9.5 There may not be a manual shutoff for the warning
be positive means (other than the use of hydraulic pressure) to
device used to satisfy 13.6.9.4.
keep the landing gear extended.
13.6.9.6 The flap position sensing unit for the warning
13.6.6 For landplanes with retractable landing gear that
device used to satisfy 13.6.9.4 may be installed at any suitable
cannot be extended manually, there must be means to extend
location.
the landing gear in the event of either: any reasonably probable
13.6.9.7 The system for the warning device used to satisfy
failure in the normal landing gear operation system; or, any
13.6.9.4 may use any part of the system (including the aural
reasonably probable failure in a power source that would
warning device) for the warning device used to satisfy 13.6.9.1.
prevent the operation of the normal landing gear operation
13.6.10 For aircraft with retractable landing gear, if the
system.
landing gear bay is used as the location for equipment other
13.6.7 For aircraft with retractable landing gear, the proper
than the landing gear, that equipment must be designed and
functioning of the retracting mechanism must be shown by
installed to minimize damage from items such as a tire burst, or
operation tests.
rocks, water, and slush that may enter the landing gear bay.
13.6.8 For aircraft with retractable landing gear, there must
13.6.11 If nose/tail wheel steering is installed, movement of
be a landing gear position indicator (as well as necessary
the pilot’s steering control must not result in a condition that
switches to actuate the indicator) or other means to inform the
would interfere with the retraction or extension of the landing
pilot that each gear is secured in the extended (or retracted)
gear.
position.
13.7 Wheels:
13.6.8.1 If switches are used, they must be loc
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F3061/F3061M − 23a F3061/F3061M − 23b
Standard Specification for
Systems and Equipment in Aircraft
This standard is issued under the fixed designation F3061/F3061M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This specification covers the systems and equipment aspects of airworthiness and design for aircraft. The material was
developed through open consensus of international experts in general aviation. This information was created by focusing on Level
1, 2, 3, and 4 Normal Category aeroplanes. The content may be more broadly applicable; it is the responsibility of the Applicant
to substantiate broader applicability as a specific means of compliance. The topics covered within this specification are: Basic
Information, Electrical Systems, Environmental Requirements, Manual Flight Controls, Automatic Flight Controls, Flight Data and
Voice Recording, Hazard Mitigation, Hydraulic Systems, Instrumentation, Mechanical Systems and Equipment, Exterior Lighting,
Oxygen Systems, Pneumatic Systems, Lightning Protection, and High-Intensity Radiated Field (HIRF) Protection.
1.2 An applicant intending to propose this information as Means of Compliance for a design approval must seek guidance from
their respective oversight authority (for example, published guidance from applicable civil aviation authorities (CAAs) concerning
the acceptable use and application thereof. For information on which oversight authorities have accepted this standard (in whole
or in part) as an acceptable Means of Compliance to their regulatory requirements (hereinafter “the Rules”), refer to the ASTM
Committee F44 web page (www.astm.org/COMMITTEE/F44.htm).
1.3 This document may present information in either SI units, English Engineering units, or both; the values stated in each system
may not be exact equivalents. Each system shall be used independently of the other; combining values from the two systems may
result in nonconformance with the standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 Following is a list of external standards referenced throughout this specification; the earliest revision acceptable for use is
indicated. In all cases later document revisions are acceptable if shown to be equivalent to the listed revision, or if otherwise
formally accepted by the governing civil aviation authority; earlier revisions are not acceptable.
This specification is under the jurisdiction of ASTM Committee F44 on General Aviation Aircraft and is the direct responsibility of Subcommittee F44.50 on Systems
and Equipment.
Current edition approved Sept. 1, 2023Oct. 1, 2023. Published September 2023November 2023. Originally approved in 2015. Last previous edition approved in 2023 as
F3061/F3061M–23. DOI: 10.1520/F3061_F3061M-23A.–23a. DOI: 10.1520/F3061_F3061M-23B.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F3061/F3061M − 23b
2.2 ASTM Standards:
F3060 Terminology for Aircraft
F3083/F3083M Specification for Emergency Conditions, Occupant Safety and Accommodations
F3116/F3116M Specification for Design Loads and Conditions
F3117/F3117M Specification for Crew Interface in Aircraft
F3153 Specification for Verification of Aircraft Systems and Equipment
F3173/F3173M Specification for Aircraft Handling Characteristics
F3179/F3179M Specification for Performance of Aircraft
F3227/F3227M Specification for Environmental Systems in Aircraft
F3228 Specification for Flight Data and Voice Recording in Small Aircraft
F3230 Practice for Safety Assessment of Systems and Equipment in Small Aircraft
F3231/F3231M Specification for Electrical Systems for Aircraft with Combustion Engine Electrical Power Generation
F3232/F3232M Specification for Flight Controls in Small Aircraft
F3233/F3233M Specification for Flight and Navigation Instrumentation in Aircraft
F3234/F3234M Specification for Exterior Lighting in Small Aircraft
F3236 Specification for High Intensity Radiated Field (HIRF) Protection in Small Aircraft
F3309/F3309M Practice for Simplified Safety Assessment of Systems and Equipment in Small Aircraft
F3316/F3316M Specification for Electrical Systems for Aircraft with Electric or Hybrid-Electric Propulsion
F3367 Practice for Simplified Methods for Addressing High-Intensity Radiated Fields (HIRF) and Indirect Effects of Lightning
on Aircraft
F3532 Practice for Protection of Aircraft Systems from Intentional Unauthorized Electronic Interactions
2.3 SAE Standard:
SAE ARP4754, Rev A Guidelines for Development of Civil Aircraft Systems
2.4 Other Standards:
AC/AMC 20-136 Protection of Aircraft Electrical/Electronic Systems against the Indirect Effects of Lightning
FAA-S-8081-14B, Change 5 Private Pilot Practical Test Standards for Airplane
RTCA DO-178, Rev B Software Considerations in Airborne Systems and Equipment Certification
RTCA DO-254 Design Assurance Guidance for Airborne Electronic Hardware
3. Terminology
3.1 Terminology specific to this standard is provided below. For general terminology, refer to Terminology F3060.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 closed, adj—in door systems (reference 13.12), means the door has been placed within the doorframe in such a position that
the latches can be operated to the “latched” condition. Fully closed means the door is placed within the doorframe in the position
it will occupy when the latches are in the latched condition.
3.2.2 continued safe flight and landing, n—continued safe flight and landing is defined as the capability for continued controlled
flight and landing, possibly using emergency procedures, but without requiring pilot skill beyond that needed to pass the Private
Pilot Practical Test Standard for Airplane (refer to FAA-S-8081-14B), or requiring pilot forces beyond those defined in
Specification F3173/F3173M. Landing may occur either at an airport or at an emergency landing location consistent with
established emergency procedures. Some aircraft damage may be realized, either during flight or upon landing.
3.2.3 door, n—in door systems (reference 13.12), a movable barrier that is located on the exterior of the fuselage or in the primary
pressure vessel on a pressurized aircraft with the intention to permit access or to enter/exit. The movable barrier must be opened
and closed without the use of tools to operate.
3.2.4 development assurance level, n—a development assurance level is an indication of the level of those planned and systematic
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from SAE International (SAE), 400 Commonwealth Dr., Warrendale, PA 15096, http://www.sae.org.
Available from Federal Aviation Administration (FAA), 800 Independence Ave., SW, Washington, DC 20591, http://www.faa.gov.
Available from RTCA, 1150 18th NW, Suite 910, Washington, DC 20036, https://www.rtca.org.
F3061/F3061M − 23b
actions used to substantiate, to an adequate level of confidence, that errors in requirements, design, and implementation have been
identified and corrected such that the system satisfies the applicable certification basis.
3.2.5 latched, adj—in door systems (reference 13.12), means the latches are fully engaged with their structural counterparts and
held in position by the latch operating mechanism.
3.2.6 latches, n—in door systems (reference 13.12), movable mechanical elements that, when engaged, prevent the door from
opening.
3.2.7 locked, adj—in door systems (reference 13.12), means the locks are fully engaged.
3.2.8 locks, n—in door systems (reference 13.12), mechanical elements, in addition to the latch operating mechanism, that monitor
the latch positions and, when engaged, prevent latches from becoming disengaged.
3.2.9 pneumatic system elements, n—components associated with systems that use bleed air or other sources of compressed gas
for their function (ice protection, vapor cycle cooling, rudder bias, door seal inflation, brake heating, emergency gear extension,
emergency braking, etc.) Within the context of pressurization systems, pneumatic system elements include the valve(s) that
regulates cabin inflow as well as all upstream equipment items that utilize bleed air; refer to 3.2.43.2.10.
3.2.10 pressurization system elements, n—components downstream of the valve(s) that regulates cabin inflow; refer to 3.2.33.2.9.
3.2.11 primary function, n—a primary function is a function that is installed to comply with applicable requirements for a required
function and that provides the most pertinent controls or information instantly and directly to the pilot.
3.2.12 primary system, n—a primary system is a system that provides a primary function.
3.2.13 secondary system, n—a secondary system is a redundancy system that provides the same function as the primary system.
3.2.14 unsafe system operating condition, n—an unsafe system operating condition is any system operating condition which, if
not detected and properly accommodated by crew action, would cause one or more serious injuries.
4. Basic Information
NOTE 1—The requirements of this chapter are applicable to all systems and equipment installed in the aircraft. These requirements are in addition to and
do not supersede any additional system specific requirements identified elsewhere in these design standards or contained in the rules of the governing
civil aviation authority.
4.1 Function and Installation:
4.1.1 Each item of installed equipment must be of a kind and design appropriate to its intended function.
4.1.2 Each item of installed equipment must be marked in a way that makes it clear to an installer the equipment’s identification,
function, or operating limitations, or any applicable combination of these factors. It is acceptable to reference equipment
installation manuals for function or limitation information.
4.1.3 Each item of installed equipment must be installed according to limitations specified for that equipment.
4.1.4 Each item of installed equipment must function properly when installed.
4.1.5 The aircraft systems and equipment required for type certification or by operating rules must be designed and installed so
that they perform as intended under the aircraft operating and environmental conditions.
NOTE 2—The intent of this requirement is to provide assurance that the required systems and equipment will function as intended in the expected operating
and environmental conditions. It is recognized that random failures will occur throughout the aircraft life and that the failed device may no longer
“perform as intended.” The acceptability of such failures or combination of failures and their associated risks are addressed under the requirements of
4.2.
F3061/F3061M − 23b
4.1.6
Level 1 and Low-Stall and Day-VFR All Others
Reserved All aircraft systems and equipment must be designed and installed so that they do not adversely affect the safety
of the aircraft or its occupants.
4.1.7 All aircraft systems and equipment must be designed and installed so that they do not adversely affect the proper functioning
of those systems or equipment, or both, covered by 4.1.5.
4.1.8 Those systems and equipment not required for type certification or by operating rules are not required to perform their
intended function under all aircraft operating and environmental conditions, provided that the resultant failure conditions are
classified as “Negligible Failure Condition” in the assessment conducted per 4.2.1; refer to Practice F3230.
4.1.8.1 Non-required systems and equipment with failure conditions classified more severe than “Negligible Failure Condition”
are not required to perform their intended function under all aircraft operating and environmental conditions, provided the failure
is appropriately annunciated to the crew.
4.1.8.2 When addressing the requirements of 4.2, if any credit is taken for the installation, or any aspect, of these non-required
systems, the portion of the system for which credit is taken must comply with 4.1.4.
4.2 System Safety Requirements:
4.2.1 An assessment of the aircraft and system functions must be performed to identify and classify the various Failure Conditions
associated with each function.
4.2.1.1 Practice F3230 provides one method of satisfying 4.2 for all normal category aircraft.
4.2.1.2 Practice F3309/F3309M provides one method of satisfying 4.2 for a limited set of aircraft as defined in that practice.
4.2.2 The equipment, systems, and installations must be designed to minimize hazards to the aircraft in the event of a probable
malfunction or failure.
4.2.2.1
Level 1 and Low-Stall and Day-VFR All Others
Reserved The aircraft systems and associated components, considered separately and in relation to other systems, must be
designed and installed so that each Catastrophic Failure Condition is “extremely improbable.”
4.2.2.2
Level 1 and Low-Stall and Day-VFR All Others
Reserved The aircraft systems and associated components, considered separately and in relation to other systems, must be
designed and installed so that each Hazardous Failure Condition is “extremely remote.”
4.2.2.3
Level 1 and Low-Stall and Day-VFR All Others
Reserved The aircraft systems and associated components, considered separately and in relation to other systems, must be
designed and installed so that each Major Failure Condition is “remote.”
F3061/F3061M − 23b
4.2.2.4
Level 1 and Low-Stall and Day-VFR All Others
Reserved For definitions of the failure condition severities and the qualitative probability terms used in 4.2.2, refer to
Practice F3230.
4.2.3 As used in 4.2, the term “systems” refers to all pneumatic systems, fluid systems, electrical systems, mechanical systems,
and powerplant systems included in the aircraft design except as provided in 4.2.3.14.2.3.1 – 4.2.3.3 through 4.2.3.3.
4.2.3.1 Powerplant systems provided as part of the type-certified engine are not subject to the provisions of 4.2.
4.2.3.2 The flight structure (such as wing, fuselage, empennage, engine-mounting, control surfaces and their associated simple
systems, and landing gear and their primary attachments) are not subject to the provisions of 4.2.
4.2.3.3 Single failures within brake systems, including associated systems and components, are not subject to the provisions of
4.2 provided it is shown that the aircraft can be brought to rest, with a braked-roll stopping distance of not more than two times
that obtained in determining the landing distance per Specification F3179/F3179M, following:
(1) Failure of any electrical, pneumatic, hydraulic, or mechanical connecting or transmitting element; or
(2) Loss of any single source of hydraulic or other brake-operating energy.
NOTE 3—The allowances of 4.2.3.3 have traditionally been applied only to jet aircraft with high takeoff and landing speeds.
4.2.4
Level 1 and Low-Stall and Day-VFR All Others
Reserved Based on the results of the assessment per 4.2.1, the depth of analysis required to show compliance may be
determined in accordance with Practice F3230 or Practice F3309/F3309M.
4.2.5 Reserved
4.2.6
Level 1 and Low-Stall and Day-VFR All Others
Reserved Information concerning an unsafe system operating condition must be provided in a timely manner to the crew to
enable them to take appropriate corrective action; refer to 3.2.8.
Reserved Information concerning an unsafe system operating condition must be provided in a timely manner to the crew to
enable them to take appropriate corrective action; refer to 3.2.14.
4.2.6.1
Level 1 and Low-Stall and Day-VFR All Others
Reserved In showing compliance with the provisions of 4.2.6, if immediate pilot awareness and immediate or subsequent
corrective action is required, the information required by 4.2.6 must be presented in accordance with Specification
F3117/F3117M.
4.2.6.2
Level 1 and Low-Stall and Day-VFR All Others
Reserved In showing compliance with the provisions of 4.2.6, one method of assessing an unsafe system operating
condition is presented in Appendix X2.
F3061/F3061M − 23b
4.3 Systems and Equipment, Network Information Security Protection:
4.3.1
Level 1 and Low-Stall and Day-VFR All Others
Reserved Connectivity of aircraft systems to external networks or devices can lead to an increased risk of intentional
unauthorized electronic interactions (IUEI). Aircraft systems and equipment must have mitigations to protect
against failure conditions that could result from IUEI.
4.3.2 When aircraft systems are connected to external networks or devices, a security assessment must be performed that:
4.3.2.1
Level 1 and Low-Stall and Day-VFR All Others
Reserved Identifies any security risks that could lead to abnormal system operation that would be considered a failure
condition;
4.3.2.2
Level 1 and Low-Stall and Day-VFR All Others
Reserved Demonstrates that adequate mitigations have been provided to prevent the failure condition from occurring. The
mitigations must be shown to be appropriate for the severity of failure condition that they protect against.
4.3.3 Practice F3532 is an acceptable method of meeting 4.3.1 and 4.3.2.
4.4 Software and Airborne Electronic Hardware:
Level 1 and Low-Stall and All other Level 1 and level 2 All Others
Day-VFR
Reserved Software and airborne electronic hardware can be addressed via Software and airborne electronic hardware must be addressed via
development assurance in accordance with 4.4.1 development assurance in accordance with 4.4.1.
Or
Via System level verification in accordance with 4.4.2.
4.4.1 Development Assurance—Software and Airborne Electronic Hardware must be designed with the appropriate Development
Assurance Level (DAL) as specified in Table 1 or in accordance with the Development Assurance Level assignment methodology
outlined in SAE ARP4754; refer to 3.2.23.2.4.
TABLE 1 Development Assurance Level Requirements
A
Classification of Failure Conditions
Negligible Minor Major Hazardous Catastrophic
A
Assessment Level
Software (SW) and Airborne Electronic Hardware (AEH)
B
Development Assurance Levels (DALs)
I P=D P=C, S=D P=C, S=D P=C, S=C
C C C
(See ) (See ) (See )
II No SW P=D P=C, S=D P=C, S=C P=C, S=C
C C C
and/or (See ) (See ) (See )
III HW DAL P=D P=C, S=D P=C, S=C P=B, S=C
C C C
Requirement (See ) (See ) (See )
IV P=D P=C, S=D P=B, S=C P=A, S=B
C C C
(See ) (See ) (See )
A
Refer to Practice F3230.
B
The letters of the alphabet used above denote the typical SW and AEH DALs. “P” indicates the primary system; “S” indicates the secondary system; “A,” “B,” “C,” and
“D” indicate the DAL in accordance with RTCA DO-178 or RTCA DO-254 as applicable. For example, an indication of “P=A” would translate to a SW or AEH DAL of “A”
on the primary system.
C
A secondary system is not necessarily required; however, if a secondary system is needed to meet the probability goals of Practice F3230, then that secondary system
must meet the stated DAL goal.
F3061/F3061M − 23b
4.4.1.1 Once a DAL has been assigned, RTCA DO-178 provides an acceptable means to satisfy the requirements of 4.4.1 for
software and DO-254 provides an acceptable means to satisfy 4.4.1 for AEH; refer to Section 2.
4.4.2 System Level Verification—Software and airborne electronic hardware within systems and equipment installed in certification
level 1 and 2 normal category aircraft may be approved using system level verification.
4.4.2.1 Specification F3153 provides an acceptable method to meet the requirements of 4.4.2; Refer to Section 2.
NOTE 4—The acceptability of this method varies between regulatory agencies. It is generally not considered an acceptable approach for complex, novel
systems such as fly-by-wire or propulsion systems. The applicant must seek individual guidance from their respective CAA concerning the use of system
level verification.
5. Electrical Systems
5.1 Electrical System Requirements—In addition to the applicable requirements of this specification, electrical systems shall
comply with the provisions of 5.1.1 and 5.1.2.
5.1.1 Electrical systems for aircraft equipped with combustion-engine propulsion shall comply with the provisions of Specification
F3231/F3231M.
5.1.2 Electrical systems for aircraft equipped with electric propulsion shall comply with the provisions of Specification
F3316/F3316M.
6. Environmental Requirements
6.1 Ventilation Requirements—In addition to the applicable requirements of this specification, ventilation systems shall comply
with the corresponding provisions of Specification F3227/F3227M.
6.2 Pressurization Requirements—In addition to the applicable requirements of this specification, pressurization systems shall
comply with the corresponding provisions of Specification F3227/F3227M.
7. Manual Flight Controls
7.1 Manual Flight Control Requirements—In addition to the applicable requirements of this specification, manual flight controls
shall comply with the corresponding provisions of Specification F3232/F3232M.
8. Automatic Flight Controls
8.1 Automatic Flight Control Requirements—In addition to the applicable requirements of this specification, automatic flight
controls shall comply with the corresponding provisions of Specification F3232/F3232M.
9. Flight Data and Voice Recording
9.1 Flight Recorder Requirements—In addition to the applicable requirements of this specification, flight data and voice recording
installations shall comply with the provisions of Specification F3228.
10. Hazard Mitigation
10.1 Takeoff Warning System:
Level 1 All Others
Reserved Unless it can be shown that a lift or longitudinal trim device that affects the takeoff performance of the aircraft
would not give an unsafe takeoff configuration when selected out of an approved takeoff position, a takeoff
warning system must be installed and meet the requirements of 10.1.1 through 10.1.4.
Reserved Unless it can be shown that a lift or longitudinal trim device that affects the takeoff performance of the aircraft
would not give an unsafe takeoff configuration when selected out of an approved takeoff position, a takeoff
warning system must be installed and meet the requirements of 10.1.1 – 10.1.4.
F3061/F3061M − 23b
10.1.1
Level 1 All Others
Reserved In showing compliance with 10.1, the system must provide to the pilots an aural warning that is automatically
activated during the initial portion of the takeoff roll if the aircraft is in a configuration that would not allow a safe
takeoff.
10.1.2
Level 1 All Others
Reserved The warning provided in accordance with 10.1.1 must continue until the configuration is changed to allow safe
takeoff, or action is taken by the pilot to abandon the takeoff roll.
10.1.3
Level 1 All Others
Reserved In showing compliance with 10.1, the means used to activate the system must function properly for all authorized
takeoff power settings and procedures and throughout the ranges of takeoff weights, altitudes, and temperatures
for which certification is requested.
10.1.4
Level 1 All Others
Reserved For the purpose of showing compliance with 10.1, an unsafe takeoff configuration is the inability to rotate or the
inability to prevent an immediate stall after rotation. This section is not intended to apply to control locks; refer to
Specification F3232/F3232M.
.
10.2 Pilot Compartment—For each pilot compartment, the pilot and the aerodynamic controls listed in Specification F3117/
F3117M, excluding cables and control rods, must be suitably protected from items of mass departing a propeller.
10.2.1 The provisions of 10.2 may be met by ensuring that no part of the pilot or the controls lies in the region between the plane
of rotation of any inboard propeller and the surface generated by a line passing through the center of the propeller hub making an
angle of 5° forward or aft of the plane of rotation of the propeller.
10.3 Flammable Fluid Fire Protection:
10.3.1 Lines, tanks, or equipment containing fuel, oil, or other flammable fluids may not be installed in compartments to be used
by the crew or passengers unless adequately shielded, isolated, or otherwise protected so that any breakage or failure of such an
item would not create a hazard.
10.3.2 In each area where flammable fluids or vapors might escape by leakage of a fluid system, there must be means to minimize
the probability of ignition of the fluids and vapors, and the resultant hazard if ignition does occur; compliance must be shown by
analysis or test.
10.3.3
Level 1 All Others
Reserved Possible sources and paths of fluid leakage, and means of detecting leakage, must be considered when showing
compliance with 10.3.2.
10.3.4
Level 1 All Others
Reserved Flammability characteristics of fluids, including effects of any combustible or absorbing materials, must be
considered when showing compliance with 10.3.2.
F3061/F3061M − 23b
10.3.5
Level 1 All Others
Reserved Possible ignition sources, including electrical faults, overheating of equipment, and malfunctioning of protective
devices, must be considered when showing compliance with 10.3.2.
10.3.6
Level 1 All Others
Reserved Means available for controlling or extinguishing a fire, such as stopping flow of fluids, shutting down equipment,
fireproof containment, or use of extinguishing agents, must be considered when showing compliance with 10.3.2.
10.3.7
Level 1 All Others
Reserved Ability of aircraft components that are critical to safety of flight to withstand fire and heat must be considered
when showing compliance with 10.3.2.
10.3.8
Level 1 All Others
Reserved If action by the flight crew is required to prevent or counteract a fluid fire (for example, equipment shutdown or
actuation of a fire extinguisher), quick acting means must be provided to alert the crew.
10.3.9
Level 1 All Others
Reserved Each area where flammable fluids or vapors might escape by leakage of a fluid system must be identified and
defined.
10.4 Fire Protection of Cargo and Baggage Compartments:
10.4.1 Sources of heat within each cargo and baggage compartment that are capable of igniting the compartment contents must
be shielded and insulated to prevent such ignition.
F3061/F3061M − 23b
10.4.2
Level 1 All Others
Level 4 All Others
If the requirements of either 10.4.3 or 10.4.4 are not met, each cargo and baggage compartment must be located Reserved
where the presence of a fire would be easily discovered by the pilots when seated at their duty station, or it must
be equipped with a smoke or fire detector system to give a warning at the pilots’ station, and provide sufficient
access to enable a pilot to effectively reach any part of the compartment with the contents of a hand held fire
extinguisher.
10.4.3
Level 1 All Others
Level 4 All Others
If the requirements of either 10.4.2 or 10.4.4 are not met, each cargo and baggage compartment must be Reserved
equipped with a smoke or fire detector system to give a warning at the pilots’ station. In addition, each
compartment must meet the requirements of Specification F3083/F3083M.
10.4.4
Level 1 All Others
Level 4 All Others
If the requirements of either 10.4.2 or 10.4.3 are not met, each cargo and baggage compartment must be Reserved
constructed and sealed to contain any fire within the compartment.
10.5 Fire Protection of Flight Controls—Flight controls located in designated fire zones, or in adjacent areas that would be
subjected to the effects of fire in the designated fire zones, must be constructed of fireproof material or be shielded so that they
are capable of withstanding the effects of a fire.
10.6 Lines, Fittings, and Components:
10.6.1 Except as provided in 10.6.3 and 10.6.4, components, lines, and fittings must be shielded or located so as to safeguard
against the ignition of leaking flammable fluid.
10.6.2 Except as provided in 10.6.3 and 10.6.4, flexible hose assemblies (hose and end fittings) must be shown to be suitable for
the particular application.
10.6.3 Subsections 10.6.1 and 10.6.2 do not apply to lines, fittings, and components, which are already approved as part of the
type certificated engine.
10.6.4 Subsections 10.6.1 and 10.6.2 do not apply to vent and drain lines, and their fittings, whose failure will not result in, or
add to, a fire hazard.
10.7 Shutoff Means:
10.7.1
Single Engine All Others
Reserved Each engine installation must have means to shut off or otherwise prevent hazardous quantities of flammable
liquids from flowing into, within, or through any engine compartment, except in lines, fittings, and components
forming an integral part of an engine.
10.7.2
Single Engine All Others
Reserved The closing of the fuel shutoff valve for any engine may not make any fuel unavailable to the remaining engines
that would be available to those engines with that valve open.
F3061/F3061M − 23b
10.7.3
Single Engine All Others
Reserved Operation of any shutoff means may not interfere with the later emergency operation of other equipment such as
propeller feathering devices.
F3061/F3061M − 23b
10.7.4
Single Engine All Others
Reserved Each shutoff must be outside of the engine compartment unless an equal degree of safety is provided with the
shutoff inside the compartment.
10.7.5
Single Engine All Others
Reserved Not more than 0.95 L [0.25 US gal] of flammable fluid may escape into the engine compartment after engine
shutoff. For those installations where the flammable fluid that escapes after shutdown cannot be limited to 0.95 L
[0.25 US gal], it must be demonstrated that this greater amount can be safely contained or drained overboard.
10.7.6
Single Engine All Others
Reserved There must be means to guard against inadvertent operations of each shutoff means, and to make it possible for
the crew to reopen the shutoff means in flight after it has been closed.
10.7.7
Single Engine All Others
Reciprocating Engine Aircraft Turbine Engine Aircraft
Reserved Engine installations need not have an engine oil system shutoff if the conditions of 10.7.7.1 and 10.7.7.2 are met.
10.7.7.1
Single Engine All Others
Reciprocating Engine Aircraft Turbine Engine Aircraft
Reserved To comply with 10.7.7, the oil tank must be integral with, or mounted on, the engine.
10.7.7.2
Single Engine All Others
Reciprocating Engine Aircraft Turbine Engine Aircraft
Reserved To comply with 10.7.7, all oil system components external to the engine must be fireproof or located in areas not
subject to engine fire conditions.
10.7.8 Power operated shut off valves must have means to indicate to the flight crew when the valve has reached the selected
position and must be designed so that the valve will not move from the selected position under vibration conditions likely to exist
at the valve location.
10.8
Single Engine All Others
Reserved Engine-driven accessories essential to safe operation must be distributed among two or more engines so that the
failure of any one engine will not impair safe operation through the malfunctioning of these accessories.
10.9 Equipment Containing High Energy Rotors:
10.9.1 High energy rotors contained in equipment such as Auxiliary Power Units (APUs) and constant speed drive units must be
able to withstand damage caused by malfunctions, vibration, abnormal speeds, and abnormal temperatures.
10.9.2 Auxiliary rotor cases in equipment such as Auxiliary Power Units (APUs) and constant speed drive units must be able to
contain damage caused by the failure of high energy rotor blades.
F3061/F3061M − 23b
10.9.3 Equipment control devices, systems, and instrumentation must reasonably ensure that no operating limitations affecting the
integrity of high energy rotors in equipment such as Auxiliary Power Units (APUs) and constant speed drive units will be exceeded
in service.
10.9.4 As an alternative to 10.9.110.9.1 – 10.9.3 through 10.9.3, it may be shown by test that equipment containing high energy
rotors can contain any failure of a high energy rotor that occurs at the highest speed obtainable with the normal speed control
devices inoperative.
10.9.5 As an alternative to 10.9.110.9.1 – 10.9.4 through 10.9.4, equipment containing high energy rotors may be located where
rotor failure will neither endanger the occupants nor adversely affect continued safe flight.
11. Hydraulic Systems
11.1 Hydraulic Systems:
11.1.1 Each hydraulic system and its elements must withstand, without yielding, the structural loads expected in addition to
hydraulic loads.
11.1.2 A means to verify the quantity of hydraulic fluid in the system must be provided.
11.1.3 A means to indicate the pressure in each hydraulic system which supplies two or more primary functions must be provided
to the flight crew.
11.1.4 There must be means to ensure that the pressure, including transient (surge) pressure, in any part of the system will not
exceed the safe limit above design operating pressure.
11.1.5 There must be means to prevent excessive pressure resulting from fluid volumetric changes in all lines which are likely to
remain closed long enough for such changes to occur.
11.1.6 The minimum design burst pressure must be 2.5 times the operating pressure.
11.1.7 Each system must be substantiated by proof pressure tests.
11.1.7.1 When proof tested, no part of any system may fail, malfunction, or experience a permanent set.
11.1.7.2 The proof load of each system must be at least 1.5 times the maximum operating pressure of that system.
11.1.8 A hydraulic accumulator or reservoir may be installed on the engine side of any firewall if: it is an integral part of an engine
or propeller system; or, the reservoir is nonpressurized and the total capacity of all such nonpressurized reservoirs is 0.95 L [0.25
US gal] or less.
12. Instrumentation
12.1 Instrumentation Requirements—In addition to the applicable requirements of this specification, instrumentation shall comply
with the provisions of Specification F3233/F3233M.
13. Mechanical Systems & Equipment
13.1 Landing Gear:
F3061/F3061M − 23b
13.1.1
Level 1 All Others
Level 4 All Others
The main landing gear system must be designed so that if it fails due to overloads during takeoff and landing Reserved
(assuming the overloads to act in the upward and aft directions), the failure mode is not likely to cause the spillage
of enough fuel from any part of the fuel system to constitute a fire hazard.
13.1.2
Level 1 All Others
Level 4 All Others
Compliance with the provisions of 13.1.1 may be shown by analysis or tests, or both. Reserved
13.2 Shock Absorption Tests:
13.2.1 Except as provided in 13.2.1.113.2.1.1 – 13.2.1.3 through 13.2.1.3, it must be shown by energy absorption tests that the
limit load factors selected for design in accordance with Specification F3116/F3116M for takeoff and landing weights will not be
exceeded.
13.2.1.1 For increases in previously approved takeoff or landing weights, or both, the requirements of 13.2.1 may be shown by
analysis based on tests conducted on a landing gear system with identical energy absorption characteristics.
13.2.1.2
Level 1 and Low-Stall All Others
The requirements of 13.2.1 may be shown by analysis based on previously approved wheel-type landing gear on Reserved
aircraft with similar weights and performance.
13.2.1.3
Level 1 and Low-Stall All Others
The requirements of 13.2.1 may be shown by analysis based on landing gear for which adequate experience and Reserved
substantiating data are available.
13.2.2 The landing gear may not fail, but may yield, in a test showing its reserve energy absorption capacity, simulating a descent
velocity of 1.2 times the limit descent velocity, assuming wing lift equal to the weight of the aeroplane.
13.3 Limit Drop Tests:
13.3.1 If compliance with 13.2.1 is shown by free drop tests, these tests must be made on the complete aeroplane, or on units
consisting of wheel, tire, and shock absorber, in their proper relation, from free drop heights not less than those determined by the
following formula in conjunction with Table 2:
1⁄2
W
h 5 C· (1)
S D
S
13.3.1.1 In complying with the requirements of 13.3.1, the free drop height may not be less than 0.234 m [9.2 in.] and need not
be more than 0.475 m [18.7 in.].
TABLE 2 Legend for Drop Test Height Formula
Variable Value SI Units English Units
h Height of Free Drop Test m in.
C Unit Correction Factor 0.0414 3.6
W Design Maximum Takeoff Weight kg lb
m
2 2
S Wing Area (including fuselage projection) m ft
F3061/F3061M − 23b
13.3.2 If the effect of wing lift is provided for in free drop tests, the landing gear must be dropped with an effective weight equal
to that derived from the following formula in conjunction with Table 3:
h1@d · ~1 2 L!#
W 5 W· (2)
S D
e
h1d
13.3.3 The limit inertia load factor must be determined in a rational or conservative manner, during the drop test, using a landing
gear unit attitude, and applied drag loads, that represent the landing conditions.
13.3.4 The value of d used in the computation of W in 13.3.2 may not exceed the value actually obtained in the drop test.
e
13.3.5 The limit inertia load factor must be determined from the drop test in 13.3.2 according to the following formula in
conjunction with Table 4:
n ·W
j e
n 5 1L (3)
W
13.3.6 The value of n determined in accordance with 13.3.5 may not be more than the limit inertia load factor used in the landing
conditions in Specification F3116/F3116M.
13.4 Ground Load Dynamic Tests:
13.4.1 If compliance with the ground load requirements of Specification F3116/F3116M is shown dynamically by drop test, one
drop test must be conducted that meets the requirements of 13.3 except that the drop height must be either: 2.25 times the drop
height prescribed in 13.3.1; or, sufficient to develop 1.5 times the limit load factor.
13.4.2 The critical landing condition for each of the design conditions specified in Specification F3116/F3116M must be used for
proof strength.
13.5 Reserve Energy Absorption Drop Tests:
13.5.1 If compliance with the reserve energy absorption requirements in 13.2.2 is shown by free drop tests, the drop height may
not be less than 1.44 times that specified in 13.3.
13.5.2 If the effect of wing lift is provided for, the units must be dropped with an effective weight equal to that derived from the
following formula in conjunction with Table 5:
h
W 5 W· (4)
S D
e
h1d
13.6 Landing Gear Extension / Retraction Systems:
TABLE 3 Legend for Effective Weight Formula
Variable Value SI Units English Units
W Effective Weight to be used in Drop Test kg lb
e m
h Specified Drop Height m in.
d Deflection Under Impact of the Tire at the Approved Inflation Pressure
PLUS m in.
Vertical Component of Axle Travel relative to the Drop Mass
For Main Gear Units, W
M
(Static Weight on that Unit with the Aircraft in Level Attitude, with the Nose
Wheel clear for nose-wheel type aircraft)
For Tail Gear Units, W
T
W (Static Weight on the Tail Unit with the Aircraft in the Tail-Down Attitude) kg lb
m
For Nose Wheel Units, W
N
(Vertical Component of the Static Reaction at the Nose Wheel, assuming that
the Mass of the Aircraft acts at the Center of Gravity and exerts a force of 1.0 g
Downward and 0.33 g Forward)
A
L Ratio of Assumed Wing Lift to Aircraft Weight — —
A
L need not be more than 0.667.
F3061/F3061M − 23b
TABLE 4 Legend for Limit Inertia Load Factor Formula
Variable Value SI Units English Units
n Limit Inertia Load Factor — —
n Acceleration (dv/dt, in g’s) as recorded in the Drop Test
j
PLUS — —
1.0
W Effective Weight to be used in Drop Test kg lb
e m
For Main Gear Units, W
M
(Static Weight on that Unit with the Aircraft in Level Attitude, with the Nose
Wheel clear for nose-wheel type aircraft)
For Tail Gear Units, W
T
W (Static Weight on the Tail Unit with the Aircraft in the Tail-Down Attitude) kg lb
m
For Nose Wheel Units, W
N
(Vertical Component of the Static Reaction at the Nose Wheel, assuming that
the Mass of the Aircraft acts at the Center of Gravity and exerts a force of 1.0 g
Downward and 0.33 g Forward)
A
L Ratio of Assumed Wing Lift to Aircraft Weight — —
A
L need not be more than 0.667.
TABLE 5 Legend for Reserve Energy Effective Weight Formula
Variable Value SI Units English Units
W Effective Weight to be used in Drop Test kg lb
e m
h Specified Drop Height m in
d Deflection Under Impact of the Tire at the Approved Inflation Pressure
PLUS m in
Vertical Component of Axle Travel relative to the Drop Mass
For Main Gear Units, W
M
(Static Weight on that Unit with the Aircraft in Level Attitude, with the Nose
Wheel clear for nose-wheel type aircraft)
For Tail Gear Units, W
T
W (Static Weight on the Tail Unit with the Aircraft in the Tail-Down Attitude) kg lb
m
For Nose Wheel Units, W
N
(Vertical Component of the Static Reaction at the Nose Wheel, assuming that
the Mass of the Aircraft acts at the Center of Gravity and exerts a force of 1.0 g
Downward and 0.33 g Forward)
13.6.1 For aircraft with retractable landing gear, each landing gear retracting mechanism and its supporting structure must be
designed for maximum flight load factors with the gear retracted.
13.6.2 For aircraft with retractable landing gear, each landing gear retracting mechanism and its supporting structure must be
designed for the combination of friction, inertia, brake torque, and air loads, occurring during retraction at any airspeed up to 1.6
times V with flaps retracted.
S1
13.6.3 For aircraft with retractable landing gear, each landing gear retracting mechanism and its supporting structure must be
designed for any load factor up to those specified in Specification F3116/F3116M for the flaps-extended condition.
13.6.4 For aircraft with retractable landing gear, the landing gear and retracting mechanism, including the wheel well doors, must
withstand flight loads, including loads resulting from all yawing conditions specified in Specification F3116/F3116M, with the
landing gear extended at any speed up to at least 1.6 times V with the flaps retracted.
S1
13.6.5 For aircraft with retractable landing gear, there must be positive means (other than the use of hydraulic pressure) to keep
the landing gear extended.
13.6.6 For landplanes with retractable landing gear that cannot be extended manually, there must be means to extend the landing
gear in the event of either: any reasonably probable failure in the normal landing gear operation system; or, any reasonably
probable failure in a power source that would prevent the operation of the normal landing gear operation system.
13.6.7 For aircraft with retractable landing gear, the proper functioning of the retracting mechanism must be shown by operation
tests.
13.6.8 For aircraft with retractable landing gear, there must be a landing gear position indicator (as well as necessary switches to
actuate the indicator) or other means to inform the pilot that each gear is secured in the extended (or retracted) position.
F3061/F3061M − 23b
13.6.8.1 If switches are used, they must be located and coupled to the lan
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