IEC PAS 62396-3:2007

Process management for avionics - Atmospheric radiation effects - Part 3: Optimising system design to accommodate the Single Event Effects (SEE) of atmospheric radiation

Provides guidance to those involved in the design of avionic systems and equipment. Builds on the initial guidance on the system level approach to Single Event Effects in IEC/TS 62396-1, considers some avionic systems and provides basic methods to accommodate SEE so that system hardware assurance levels may be met.

General Information

• Status: Replaced
• Publication Date: 17-Sep-2007
• ICS: 03.100.50 - Production. Production management
• ICS: 31.020 - Electronic components in general
• ICS: 49.060 - Aerospace electric equipment and systems
• Technical Committee: TC 107 - Process management for avionics
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 28-Aug-2008

Relations

• Replaced By: IEC TS 62396-3:2008 - Process management for avionics - Atmospheric radiation effects - Part 3: Optimising system design to accommodate the single event effects (SEE) of atmospheric radiation
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC/PAS 62396-3
Edition 1.0 2007-09
PUBLICLY AVAILABLE
SPECIFICATION
PRE-STANDARD
Process management for avionics – Atmospheric radiation effects –
Part 3: Optimising system design to accommodate the Single Event Effects
(SEE) of atmospheric radiation

IEC/PAS 62396-3:2007(E)
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IEC/PAS 62396-3
Edition 1.0 2007-09
PUBLICLY AVAILABLE
SPECIFICATION
PRE-STANDARD
Process management for avionics – Atmospheric radiation effects –
Part 3: Optimising system design to accommodate the Single Event Effects
(SEE) of atmospheric radiation

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
M
ICS 03.100.50; 31.020; 49.060 ISBN 2-8318-9203-1

– 2 – PAS 62396-3 © IEC:2007(E)

CONTENTS
FOREWORD.3

1 Scope and object.5

2 Normative References .5

3 Terms and definitions .5

4 Avionic Systems .5
4.1 Lift control flap and slat .6
4.2 Engine thrust.7
4.3 Systems impacted by atmospheric radiation .7
4.3.1 Aircraft system level .7
4.3.2 Electronic equipment level.7
4.3.3 Component level.8
4.4 SEE at system level .8
4.4.1 Hard errors and effects.8
4.4.2 Soft error accommodation.8
4.4.3 Component technology susceptibility .8
5 Optimisation of system design .8
5.1 Avionic system optimisation.8
5.2 Equipment level optimisation of soft error SEE .9
5.2.1 SEE Detection .9
5.2.2 Soft error accommodation, and error detection and correction .10
5.2.3 Accommodation of non-destructive hard faults.11
5.3 Component level optimisation of SEE .11
5.3.1 Use of larger geometry atmospheric SEE tolerant parts .11
5.3.2 Selective use of larger geometry atmospheric SEE tolerant parts .11
5.3.3 Use of components not subject to hard faults or errors .11
5.3.4 Use of components subject to non destructive hard faults or errors .12

Figure 1 – Lift control flap and slat.6
Figure 2 – Engine thrust.7

PAS 62396-3 © IEC:2007(E) – 3 –

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
PROCESS MANAGEMENT FOR AVIONICS –

ATMOSPHERIC RADIATION EFFECTS –

Part 3: Optimising system design to accommodate the Single Event

Effects (SEE) of atmospheric radiation

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
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A PAS is a technical specification not fulfilling the requirements for a standard but made
available to the public.
IEC-PAS 62396-3 has been processed by IEC technical committee 107: Process management
for avionics.
The text of this PAS is based on the This PAS was approved for publication
following document: by the P-members of the committee
concerned as indicated in the following
document:
Draft PAS Report on voting
107/62/NP 107/73/RVN
Following publication of this PAS, which is a pre-standard publication, the technical committee
or subcommittee concerned will transform it into an International Standard.

– 4 – PAS 62396-3 © IEC:2007(E)

This PAS shall remain valid for an initial maximum period of three years starting from 2007-09.

The validity may be extended for a single three-year period, following which it shall be revised

to become another type of normative document or shall be withdrawn

IEC/PAS 62396 consists of the following parts, under the general title Process management

for avionics – Atmospheric radiation effects:

• Part 2: Guidelines for single event effects testing for avionics systems

• Part 3: Optimising system design to accommodate the Single Event Effects (SEE) of

atmospheric radiation
• Part 4: Guidelines for designing with high voltage aircraft electronics and potential
single event effects
• Part 5: Guidelines for assessing thermal neutron fluxes and effects in avionics
systems
PAS 62396-3 © IEC:2007(E) – 5 –

PROCESS MANAGEMENT FOR AVIONICS –

ATMOSPHERIC RADIATION EFFECTS –

Part 3: Optimising system design to accommodate the Single Event
Effects (SEE) of atmospheric radiation

1 Scope and object
This PAS is intended to provide guidance to those involved in the design of avionic systems
and equipment. It builds on the initial guidance on the system level approach to Single Event
Effects in IEC/TS 62396-1, considers some avionic systems and provides basic methods to
accommodate SEE so that System Hardware Assurance levels may be met.
2 Normative references
The following referenced documents are indispensable for the application of this document,
only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
IEC/TS 62396-1, Process management for avionics – Atmospheric radiation effects – Part 1:
Accommodation of atmospheric radiation effects via single event effects within avionics
electronic equipment
IEC/TS 62239, Process management for avionics – Preparation of an electronic components
management plan
3 Terms and definitions
For the purpose of this document, the terms and definitions of IEC/TS 62396-1 and IEC/TS
62239 apply.
4 Avionic Systems
In IEC/TS 62396-1, it was detailed that systems for which failure may have the most severe
impact on the aircraft are classified as level A and require the most rigorous approach to
single event effects and parts control. Two examples of avionic systems are provided for the

purposes of clarification.
– 6 – PAS 62396-3 © IEC:2007(E)

4.1 Lift control flap and slat

The flow of air over the wing surfaces is controlled by flaps and slats, the position of the

majority of these are under the pilot’s control, redundancy may be achieved by having more

than one actuation method. See Figure 1.

Electronically powered surface

Hydromechanical drive
Figure 1 – Lift control flap and slat

PAS 62396-3 © IEC:2007(E) – 7 –

4.2 Engine thrust
The engines have to provide thrust as required by the demand and the flight profile. If the

aircraft has more than one engine, then loss of engine thrust may be accommodated by the

level of redundancy. The engine equipment may be dual redundant and have two lanes either

of which can perform the required function if the other fails. See Figure 2.

Figure 2 – Engine thrust
4.3 Systems impacted by atmospheric radiation
Atmospheric radiation may affect the electronic parts of the system. The high energy
secondary or thermal neutron radiation interacts with the silicon within semiconductor
elements of an electronic component to produce a charge which may cause SEE in the
localised area within that device, which may potentially affect the equipment and in turn the
system. Current avionic electronic systems use state of the art electronic components with
feature sizes well below 1 µm, and SEE do occur in these devices but utilising correct system
design aspects for the electronic elements an overall effect on the system performance is
avoided. This type of approach requires careful selection and maintenance of electronic
components throughout equipment level life see IEC/TS 62239.
The approach to system level optimization of design may be conducted by considering the
system at 3 levels.
4.
...