IEC TR 62396-6:2017

IEC TR 62396-6 ®
Edition 1.0 2017-07
TECHNICAL
REPORT
colour
inside
Process management for avionics – Atmospheric radiation effects –
Part 6: Extreme space weather – Potential impact on the avionics environment
and electronics
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IEC TR 62396-6 ®
Edition 1.0 2017-07
TECHNICAL
REPORT
colour
inside
Process management for avionics – Atmospheric radiation effects –

Part 6: Extreme space weather – Potential impact on the avionics environment

and electronics
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 03.100.50; 31.020; 49.060 ISBN 978-2-8322-4512-5

– 2 – IEC TR 62396-6:2017 © IEC 2017
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Abbreviated terms and acronyms . 7
5 Extreme space weather (ESW) . 8
5.1 General . 8
5.2 Space weather relevant to avionics . 8
5.3 Examples of proton spectra for GLEs . 9
5.4 GLEs in recent history . 10
5.5 GLEs inferred from historical data . 11
5.5.1 General . 11
5.5.2 The Carrington event . 11
5.5.3 The AD774-775 event . 11
5.6 Defining an extreme space weather environment . 12
5.6.1 General . 12
5.6.2 ESW level 1: February 1956 GLE . 13
5.6.3 ESW level 2: An event much larger than the February 1956 GLE,
approximately representative of a 1-in-1 000-year event . 15
5.7 Forecasting the occurrence of an extreme space weather event . 15
5.8 Acceleration factors in ground testing . 16
5.9 Real-time atmospheric radiation monitoring and aircraft in-flight radiation
monitoring . 16
6 Considerations of ESW impact on infrastructure related to flight operations . 17
Bibliography . 18

Figure 1 – 23 February 1956 GLE – Integral and differential proton spectra fitted with
band and exponential functions . 10
Figure 2 – 19 October 1989 GLE – Integral and differential proton spectra fitted with
band and exponential functions . 10
Figure 3 – Proton spectra for galactic cosmic ray background (solid red line) and
February 1956 GLE (dashed blue line), and ratio between the two (green dotted line) . 13
Figure 4 – Integral neutron spectra at ground level (top) and 12 km altitude (bottom)
for GCR and GLE conditions at two cut-off rigidities . 14

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PROCESS MANAGEMENT FOR AVIONICS –
ATMOSPHERIC RADIATION EFFECTS –

Part 6: Extreme space weather –
Potential impact on the avionics environment and electronics

FOREWORD
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 62396-6, which is a technical report, has been prepared by IEC technical
committee 107: Process management for avionics.
This first edition cancels and replaces the first edition of IEC PAS 62396-6 published in 2014.
This edition constitutes a technical revision. The technical changes with respect to the
previous edition are the contents of the present document.

– 4 – IEC TR 62396-6:2017 © IEC 2017
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
107/298/DTR 107/305/RVDTR
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62396 series, published under the general title Process
management for avionics – Atmospheric radiation effects can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

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INTRODUCTION
This document provides information intended to improve the understanding of extreme space
weather events.
Rarely occurring natural hazards can have a high impact to society and national economies.
Natural events have no respect for national boundaries and the whole world can suffer. The
April 2010 Icelandic (Eyjafjallajökull) volcano eruption and resulting ash cloud and the
March 2011 Japanese earthquake and tsunami demonstrated how devastating rarely
occurring natural events can be.
In 2011 the UK recognised “extreme space weather” (ESW) events (also referred to as solar
super storms and sometimes simply as super storms) as one of these rare, but high impact,
hazards. There is evidence of the impact of ESW events in the past. During an event in
February 1956, which was monitored at ground level, a rise in radiation flux of more than 2
orders of magnitude was derived for aircraft environments.
The document does not consider high altitude nuclear explosions or any other man-made
modifications of space weather.

.
– 6 – IEC TR 62396-6:2017 © IEC 2017
PROCESS MANAGEMENT FOR AVIONICS –
ATMOSPHERIC RADIATION EFFECTS –

Part 6: Extreme space weather –
Potential impact on the avionics environment and electronics

1 Scope
This part of IEC 62396, which is a technical report, provides information intended to improve
the understanding of extreme space weather events; it details the mechanisms and conditions
that produce “extreme space weather” (ESW) as a result of a large increase in the activity on
the surface of the sun and it discusses the potent
...