ASTM F2425-05a(2018)

Standard Specification for Continued Airworthiness System for Weight-Shift-Control Aircraft

ABSTRACT
This specification covers continued airworthiness requirements for the manufacture of weight-shift-control aircraft and their qualification for possible certification. A safety directive shall be distributed to all registered owners and appropriate CAAwhen a condition is found to exist that may also exist in other aircraft in the fleet and which would cause a deviation from original design or unsafe condition for flight, rendering the aircraft unairworthy. Service bulletins should be distributed to all registered owners by the manufacturer when no unsafe condition exists that could lead to an unairworthy condition, but a service problem has become repetitive for which the manufacturer has developed a design change, or service procedure change that will contribute to the improvement or convenience of operation or maintenance of the aircraft. The manufacturer should issue service letters on any subject that is considered helpful to the owners.
SCOPE
1.1 The following continued airworthiness requirements apply for the manufacture of weight-shift-control aircraft and their qualification for possible certification.  
1.2 This specification applies to aircraft seeking civil aviation authority approval, in the form of flight certificates, flight permits, or other like documentation.  
1.3 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 requirements prior to use.  
1.4 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: 31-Dec-2017
• ICS: 49.020 - Aircraft and space vehicles in general
• Technical Committee: F37 - Light Sport Aircraft
• Drafting Committee: F37.40 - Weight Shift

Relations

• Replaces: ASTM F2425-05a(2009) - Standard Specification for Continued Airworthiness System for Weight-Shift-Control Aircraft
• Effective Date: 01-Jan-2018
• Referred By: ASTM F3060-20 - Standard Terminology for Aircraft
• Effective Date: 01-Jan-2018
• Referred By: ASTM F3199-16a - Standard Guide for Wing Interface Documentation for Weight Shift Control Aircraft
• Effective Date: 01-Jan-2018

Overview

ASTM F2425-05a(2018): Standard Specification for Continued Airworthiness System for Weight-Shift-Control Aircraft establishes key requirements and procedures to ensure the ongoing safety and operational suitability of weight-shift-control aircraft. Developed by ASTM International’s Committee F37, this standard provides a framework for manufacturers, aircraft owners, and regulatory authorities to maintain airworthiness throughout the service life of these aircraft, especially as they pursue certification from civil aviation authorities (CAA).

Key Topics

• Continued Airworthiness Requirements: Provides guidelines for monitoring, documenting, and maintaining the airworthiness of weight-shift-control aircraft.
• Safety Directives and Communication:
  • Mandatory safety directives must be distributed to all registered owners and the relevant CAA if an unsafe condition that affects a fleet is identified.
  • Service bulletins and letters are issued to address repetitive service problems or provide helpful maintenance information but are not mandatory unless involving safety of flight.
• Documentation and Recordkeeping:
  • Manufacturers are responsible for keeping a comprehensive list of registered aircraft owners, including ownership and contact details.
  • All records documenting compliance, maintenance, and safety directives must be maintained in a secure location and be accessible, even if the manufacturer ceases operations.
• Owner Responsibilities:
  • Aircraft owners must read and comply with the manufacturer’s continued airworthiness information.
  • Owners are responsible for reporting safety or service issues and for keeping their contact details current with the manufacturer or CAA.
• Manufacturer Responsibilities:
  • Must investigate reported safety issues, issue required directives or bulletins, maintain documentation, and ensure accessible records for future support of the aircraft fleet.

Applications

ASTM F2425-05a(2018) is essential for:

• Manufacturers of Weight-Shift-Control Aircraft: This standard must be followed by aircraft manufacturers seeking civil aviation authority approval for their aircraft. It supports the certification process by ensuring ongoing compliance with safety and operational standards.
• Aircraft Owners and Operators: Owners are required to adhere to maintenance protocols, comply with safety notices, and keep their registration information updated for continued airworthiness.
• Civil Aviation Authorities (CAA): Regulatory bodies use these specifications to assess conformity during certification, issue flight certificates, and oversee fleet airworthiness.
• Maintenance Organizations: Provides standardized procedures for maintenance, service bulletin implementation, and recordkeeping to increase safety and reliability for light sport aircraft.

Related Standards

For comprehensive compliance and optimized safety, ASTM F2425-05a(2018) is often used alongside other standards related to light sport and weight-shift-control aircraft, including:

• ASTM F2245: Standard Specification for Design and Performance of Light Sport Airplane
• ASTM F2295: Standard Practice for Continued Airworthiness of Aircraft
• ASTM F2339: Standard Practice for Design and Manufacture of Aircraft
• Relevant certification and guidance documents issued by civil aviation authorities such as FAA and EASA

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By adhering to ASTM F2425-05a(2018), stakeholders in the weight-shift-control aircraft sector ensure a robust continued airworthiness system, enhance safety, and support regulatory compliance. This contributes to safer skies and reliable operations for recreational and sport aviation worldwide. The standard also aligns with internationally recognized practices under the WTO Technical Barriers to Trade (TBT) Committee, improving global acceptance for aircraft certification and operation.

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: F2425 −05a (Reapproved 2018)
Standard Specification for
Continued Airworthiness System for Weight-Shift-Control
Aircraft
This standard is issued under the fixed designation F2425; 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 4. Monitoring, Investigation, and Remedial Action
4.1 The manufacturer shall maintain contact with owners
1.1 The following continued airworthiness requirements
apply for the manufacture of weight-shift-control aircraft and who report incidents or other situations that relate to safety,
operations, or maintenance of aircraft produced and placed in
their qualification for possible certification.
service. The manufacturer shall promptly investigate all re-
1.2 This specification applies to aircraft seeking civil avia-
ported failures, malfunctions, or defects and develop the
tion authority approval, in the form of flight certificates, flight
appropriate corrective action. The magnitude of the service
permits, or other like documentation.
problem shall define the subsequent publication to the regis-
1.3 This standard does not purport to address all of the
tered owners.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
5. Safety Directives
priate safety, health, and environmental practices and deter-
5.1 A safety directive shall be distributed to all registered
mine the applicability of regulatory requirements prior to use.
owners and appropriate CAAwhen a condition is found to exist
1.4 This international standard was developed in accor-
that may also exist in other aircraft in the fleet and which would
dance with internationally recognized principles on standard-
cause a deviation from original design or unsafe condition for
ization established in the Decision on Principles for the
flight, rendering the aircraft unairworthy. This change, main-
Development of International Standards, Guides and Recom-
tenance procedure, inspection procedure, or other procedures
mendations issued by the World Trade Organization Technical
deemed appropriate by the manufacturer is mandatory and
Barriers to Trade (TBT) Committee.
must be performed and documented in the individual aircraft
logs in order for that aircraft to maintain compliance with
2. Terminology
ASTM standards.
2.1 Acronyms:
5.2 A safety directive shall not be issued to address situa-
2.1.1 AOI—Aircraft Operating Instructions
tions that do not present a safety of flight issue. These
2.1.2 CAA—Civil Aviation Authority situations include, but are not limited to, circumstances in
which service publications are issued to improve or enhance
the following:
3. Registered Operators List Documentation
5.2.1 Spare part sales;
3.1 The manufacturer shall maintain a list of registered
5.2.2 Aircraft performance, capability, or efficiency, unless
aircraft owners that includes all aircraft in service by serial
the change is needed for the aircraft to meet the minimum
number, registration number, together with the name and
design and performance standards identified in the consensus
address of the owner.
standard and the manufacturer’s statement of compliance;
3.2 In cases where the appropriate CAA maintains records
5.2.3 Aircraft appearance;
of registered owners sufficient for tracking aircraft and the
5.2.4 Aircraft maintainability; or
manufacturer has access to such records, the manufacturer may
5.2.5 Anyotheraircraftcharacteristicwhentheactioncalled
elect to utilize such records for complying with this section.
for does not remedy an unsafe condition, including those
related to reliability which do not have an impact on safety of
flight.
This specification is under the jurisdiction of ASTM Committee F37 on Light
6. Service Bulletin Documents
Sport Aircraft and is the direct responsibility of Subcommittee F37.40 on Weight
Shift.
6.1 Service bulletins should be distributed to all registered
Current edition approved Jan. 1, 2018. Published January 2018. Originally
owners by the manufacturer when no unsafe condition exists
approved in 2005. Last previous edition approved in 2009 as F2425 – 05a (2009).
DOI: 10.1520/F2425-05AR18. that could lead to an unairworthy condition, but a service
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F2425 − 05a (2018)
problem has become repetitive for which the manufacturer has they may do so by making use of the original m
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