# AD 75-26-13: Structural Flap Modification

- Type: Airworthiness directive
- Status: Current
- Products: Textron BH.125 Series 400A, BH.125 Series 600A, DH.125 Series 3A/R, DH.125 Series 3A/RA and DH.125 Series 400A
- Effective: January 15, 1976
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-2469
- Registered aircraft: 4 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/449E3D8445C4FA70862569A4006F7F96.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/75-26-13

## The airworthiness directive

75-26-13 HAWKER SIDDELEY AVIATION: Amendment 39-2469. Applies to DH-125 series 3AR, S/N 25/148 and 149; series 3ARA, S/N 25/151, 152, 153, 155, 156, 158, 159, and NA 700 through NA 710; series 400 A, S/N NA 711 through NA 752 airplanes and to BH-125 series 400 A, S/N NA 753 through NA 780; and series 600A, S/N 25/6001 through 6004, 6007, 6009, 6010, 6011, 6013, 6014, 6016, 6018, 6020, 6022 through 6026, 6032, 6034, 6038, 6040, 6044, 6046, 6047, and 6051 airplanes.

Compliance required within the next 100 hours' time in service after the effective date of this AD, unless already accomplished.

To prevent structural damage to the inboard end of the flaps which can result from landing on heavily watered, or slush, or snow covered runways, incorporate the structural modification to the inboard end of the flap (L/H & R/H) in accordance with the accomplishment instructions in Hawker Siddeley Aviation Ltd. Service Bulletin 27-112 (2426), Revision 1, dated March 11, 1975, or an FAA-approved equivalent.

This amendment becomes effective on January 15, 1976.

## 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 5 of 50 models: BH.125 Series 400A, BH.125 Series 600A, DH.125 Series 400A, DH.125 Series 3A/R, DH.125 Series 3A/RA

## 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: 4 (4 by airframe model, 0 by engine model)
- Makers: Hawker Siddeley 4

Models with the most aircraft:

- [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)

All 2 models: https://openairdocs.org/ad/75-26-13/models.md
Every aircraft: https://openairdocs.org/ad/75-26-13/aircraft.md

Its text cites no advisory circulars or STCs.

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