# AD 78-07-07: Lightning Strike Damage to Radome

- Type: Airworthiness directive
- Status: Current
- Products: Textron BH.125 Series 400A, BH.125 Series 600A, DH.125 Series 1A, DH.125 Series 1A-522, DH.125 Series 1A/R-522, DH.125 Series 1A/S-522, DH.125 Series 3A, DH.125 Series 3A/R, DH.125 Series 3A/RA, DH.125 Series 400A, HS.125 Series 600A and HS.125 Series 700A
- Effective: May 3, 1978
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-3170
- Registered aircraft: 26 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D006AAEF2A82698D862569A5007632DF.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/78-07-07

## The airworthiness directive

78-07-07 HAWKER SIDDELEY AVIATION, LIMITED: Amendment 39-3170. Applies to Model DH/BH/HS-125 airplanes, certificated in all categories, all series, up to and including the 700A series, but excluding all 700A series airplanes except S/N 0201, 0202, 0203, and 0204, and also excluding S/N 25/025.

Compliance is required as indicated, unless already accomplished.

To prevent possible lightning strike damage to the radome which could result in loss of the radome, within the next 150 hours time in service after the effective date of this AD, remove the lightning diverter strips from the radome and install new diverter strips in accordance with the section entitled "Accomplishment Instructions" and associated drawings of Hawker Siddeley Aviation, Limited, Modification Service Bulletin 53-50(2626), dated August 26, 1977, including Revision 1 (pages 1, 5, 6, and 8) dated October 4, 1977, or an FAA-approved equivalent.

This amendment becomes effective May 3, 1978.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A3EU](https://openairdocs.org/tcds/A3EU): Textron Aviation Inc.; names 12 of 50 models: HS.125 Series 600A, HS.125 Series 700A, DH.125 Series 1A/R-522, BH.125 Series 400A, BH.125 Series 600A, DH.125 Series 400A, DH.125 Series 3A/R, DH.125 Series 1A…

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 26 (26 by airframe model, 0 by engine model)
- Makers: British Aerospace 14, Hawker Siddeley 11, Raytheon 1

Models with the most aircraft:

- [British Aerospace HS 125-700A](https://openairdocs.org/model/british-aerospace-hs-125-700a): 14 aircraft (airframe model)
- [Hawker Siddeley HS.125 SERIES 700A](https://openairdocs.org/model/hawker-siddeley-hs-125-series-700a): 7 aircraft (airframe model)
- [Hawker Siddeley BH.125-400A](https://openairdocs.org/model/hawker-siddeley-bh-125-400a): 2 aircraft (airframe model)
- [Hawker Siddeley DH.125-3A/RA](https://openairdocs.org/model/hawker-siddeley-dh-125-3a-ra): 2 aircraft (airframe model)
- [Raytheon HS 125-700A](https://openairdocs.org/model/raytheon-hs-125-700a): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/78-07-07/models.md
Every aircraft: https://openairdocs.org/ad/78-07-07/aircraft.md

Its text cites no advisory circulars or STCs.

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