# AD 68-16-01: Placard To Prevent Engine Flameout

- Type: Airworthiness directive
- Status: Current
- Products: Textron 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 and DH.125 Series 400A
- Effective: August 5, 1968
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-626
- Registered aircraft: 2 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/FA709DD0EB25A9D1862569A40054A2C8.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/68-16-01

## The airworthiness directive

68-16-01 HAWKER SIDDELEY: Amendment 39-626. Applies to all Series of Model DH- 125 airplanes.

Compliance required as indicated, unless already accomplished.

To prevent engine flameouts during icing conditions, within the next 15 hours' time in service after the effective date of this AD, or before further flight into known or predicted icing conditions, whichever occurs first, install a placard on the flight instrument panel in clear view of the pilot reading as follows:

"TURN ENGINE RELIGHT SWITCH ON WHEN OPERATING ENGINE ANTI- ICING SYSTEM."

This supersedes Amendment 39-549 (33 F.R. 2504), AD 68-03-02.

This amendment becomes effective August 5, 1968.

## 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 8 of 50 models: DH.125 Series 1A/R-522, DH.125 Series 400A, DH.125 Series 3A/R, DH.125 Series 1A, DH.125 Series 1A-522, DH.125 Series 3A, DH.125 Series 1A/S-522, 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: 2 (2 by airframe model, 0 by engine model)
- Makers: Hawker Siddeley 2

Models with the most aircraft:

- [Hawker Siddeley DH.125-3A/RA](https://openairdocs.org/model/hawker-siddeley-dh-125-3a-ra): 2 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/68-16-01/models.md
Every aircraft: https://openairdocs.org/ad/68-16-01/aircraft.md

Its text cites no advisory circulars or STCs.

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