1. HIRF Regualtion Jean-Christophe LAMY 15/12/2015 MR 05.002

2. INTRODUCTION Origin? Why Effect on Systems? Composite Material
HIRF: Human (Radars, Antennas)
Why Effect on Systems?
Composite Material
Critical Computers

3. HIRF (High Intensity Radiation Field)

4. Frequency Band (10 kHz-40GHz)

5. HIRF Regulation (History)
Before 1988 in Europe
NO Regulation for HIRF Protection
Only concern at Equipment level
(Equipment qualification RTCA/DO160-B sec 20)

6. HIRF Regulation (History)
After 1988 in Europe (from A320 TypeCertificate)
With Introduction of „super“ critical systems (FADEC, FBW) and EFIS
HIRF requirements introduced via Special Conditions (CRI/SC)
CRI: Certification Review Item
SC : Special Condition

7. HIRF Regulation (History)
Requirement for Critical System
Level A system not perturbated when exposed to External Certification Envrionment
Requirement for Essential System
Level B/C systems not perturbated when exposed to External Normal Environment

8. HIRF Regulation (History)
After 1988 in USA
HIRF requirements introduced via Special Conditions (Issue Paper/SC)
Level A system not perturbated when exposed to External Certification I (Certification) or level A equipment not pertubated when exposed to 100V/m, Cat W DO160 sec20)
Level B/C NO requirements

9. HIRF Regulation (History)
In early 90’
JAA were presently developing in co-operation with the FAA, a regulatory project for HIRF (cordinated JAA/FAA Electromagnetic Effects Harmonisation Working Group).
The objective of the project is the issuance of an NPA (Notice of Proposed Amendment) in parallel with an FAA NPRM leading to a final regulation and associated advisory material and Users Guide.
The EEHWG adopted a set of HIRF environment levels in November 1998

10. HIRF JAA/EASA Policy INT POLs
JAA has temporary adopted EEHWG activity with INT POLs (INT POL25/2, 23/1, 27&29/1) with:
External HIRF Environments (Certification, Normal, Severe)
Set of requirements (Critical, Essentials)

11. Definition of the Regulatory HIRF Environments
This environment is based on the available data representing all authorised transmitters in Western Europe and the United States.
Certification HIRF Environment
Normal HIRF Environment
FREQUENCY FIELD STRENGTH (V/m)
PEAK AVERAGE
10 kHz – 500 kHz
500 kHz - 2 MHz
2 MHz - 30 MHz
30 MHz – 100 MHz
100 MHz – 200 MHz
200 MHz – 400 MHz
400 MHz - 1 GHz
1 GHz - 2 GHz 1,
2 GHz - 4 GHz 3,
4 GHz - 6 GHz 3,
6 GHz - 8 GHz
8 GHz - 12 GHz 1,
12 GHz - 18 GHz
18 GHz - 40 GHz
FREQUENCY FIELD STRENGTH (V/m)
PEAK AVERAGE
10 kHz - 2 MHz
2 MHz - 30 MHz
30 MHz MHz
100 MHz – 400 MHz
400 MHz – 700 MHz
700 MHz - 1 GHz
1 GHz - 2 GHz 2,
2 GHz - 6 GHz 3,
6 GHz - 8 GHz 1,
8 GHz - 12 GHz 3,
12 GHz - 18 GHz 2,
18 GHz - 40 GHz

12. Definition of the Regulatory HIRF Environments
Severe HIRF Environment
FREQUENCY FIELD STRENGTH (V/m)
PEAK AVERAGE
10 kHz kHz
100 kHz MHz
400 MHz – 700 MHz
700 MHz - 1 GHz
1 GHz - 2 GHz 5,
2 GHz - 4 GHz 6,
4 GHz - 6 GHz 7,
6 GHz - 8 GHz 1,
8 GHz - 12 GHz 5,
12 GHz - 18 GHz 2,
18 GHz - 40 GHz 1,

13. HIRF - Requirements
 Critical systems must function normally when the aircraft is exposed to the normal HIRF environment
Critical systems must be designed and installed such that to ensure their critical functions when the aircraft is exposed to the certification HIRF environment
Essential systems, equipment providing essential function are not affected when exposed to DO 160 Cat R/T
NB: Non-essential systems do not have regulatory constraints for HIRF

14. B or C (ESSENTIAL SYSTEM)
ENVIRONMENT
CERTIFICATION LEVEL
CERTIFICATION
NORMAL
EQUIPMENT LEVEL
A (CRITICAL SYSTEM)
Function must not be adversely affected during and after exposure to HIRF.
Any system interruptions should be evaluated to assure continued performance of the aircraft function and should be approved by the cognisant aviation certification authority.
Affected systems must automatically recover upon removal of HIRF effects, unless this conflicts with other operational or functional requirements of that system.
Systems must not be adversely affected during an after aircraft exposure to HIRF.
As required by the equipment qualification procedures.
B or C (ESSENTIAL SYSTEM)
No requirement
Equipment must not be adversely affected during and after exposure to the defined test level

15. Methods of Compliance (ED 107)
Level A system

16. Methods of Compliance (ED 107)
Level A system (classical Method for Radiated Susceptibility):
A) ESTABLISH ATTENUATION CURVES
TESTS ON SYSTEM/EQUIPMENT

17. Methods of Compliance (ED 107)
PHASE A):
GENERIC ATTENUATION CURVES (100MHz-18GHz) or
LOW LEVEL TESTS (LLSF)

18. Methods of Compliance (ED 107)
PHASE B:
The Category level = f (Ext Env * ATT curves) + Margin
Use of Categories of DO 160 Section 20

19. Generic Attenuation Curve

20. Less Classical Method  Test on Aircraft level with real threat
Similarity Approach (reuse of data of similar system
with similar location on similar Aircraft
Futur development: HIRF-SE project (virtual environment)

21. Methods of Compliance (ED 107)
Level B/C systems:
Level B system: Equipment Test
DO 160 section 20 Cat R (150 V/m peak) or
Normal HIRF Environment + Attenuation
DO 160 section 20 Cat D, E, F, G
Level C system: Equipment Test
DO 160 section 20 Cat T (5V/m average)

22. Methods of Compliance (ED 107)
DO 160 section 20 Categories

23. Regulatory References HIRF (advisory)
AC/ACJs
AC/AMC Certification of Systems for HIRF Effects
USER‘S GUIDE ED-107A/ARP5583A HIRF User‘s Guide
ED14/DO160
Section 20 HIRF

24. Latest HIRF Regulation
FAR , , 27/ published in September 2007 (adoption of HIRF NPRM) and associated AC
CS July 2015 and AMC ( , 27/ published in futur CS Adts)
Both Regulations are now harmonized

25. Applicable HIRF Regulation for new TC
Large A/C
(+ AMC for guidance)
General Aviation + Rotorcaft
HIRF/SC (+ED 107A for guidance)
( and 27/ AMC released
in the near futur)

26. Applicable HIRF Regulation for Changes/STC
(installation/modification of susceptible systems)
A/C certified before 1988
- Dedicated HIRF Special Condition/Interpretative Material based
on latest INT POL 25/2, 23/1 or 27&29/1) (Authority Request) or
- Elect to comply with latest regulation (Applicant’s Request)
(+ AMC for guidance)
(or , 27/ when new CSs released )
A/C certified after 1988
- Use of HIRF Special Condition of the TCDS or
- Elect to comply with latest AMC for
guidance(or , 27/ once CSs released)
(Applicant’s Request, if HIRF SC not based on latest INT POLs)