# AD 61-24-03: Throttle Interlock Modification

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC-8-11, DC-8-12, DC-8-21, DC-8-31, DC-8-32, DC-8-33, DC-8-41, DC-8-42, DC-8-43, DC-8-51, DC-8-52, DC-8-53 and 15 more
- Effective: November 23, 1961
- Published: November 23, 1961
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 8 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/43111FEA67B6E73C862569BC00751377.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/61-24-03

## The airworthiness directive

61-24-03 DOUGLAS: Amdt. 371 Part 507 Federal Register November 23, 1961. Applies to All DC-8 Aircraft, Serial Nos. 45252-45289, 45291-45306, 45376-45393, 45408-45413, 45416-45419, 45421-45431, 45433-45437, 45442-45445, 45526, 45565-45570, 45588-45606, 45609-45614, 45616-45628, 45636.

Compliance required within 1,000 hours' time in service after the effective date of this AD, but in no event later than February 28, 1962.

To prevent inadvertent application of forward thrust when reverse thrust is desired under emergency conditions, the following modification shall be accomplished:

Incorporate a throttle-thrust brake interlock system which will:

  (a) Prevent application of reverse thrust until the reverse buckets are in the reverse thrust position, and

  (b) Return a throttle to the detent position should the corresponding buckets move from the reverse thrust position.

The modification shall be accomplished in accordance with technical data approved by theChief, Engineering and Manufacturing Branch, FAA Western Region.

(Douglas DC-8 Service Bulletin Nos. 78-48, 78-50, 78-51 and 78-52 for DC-8 aircraft equipped with JT3C6, JT3D-1, JT4A and Rolls Royce RCO-12 engines, respectively, pertain to this same subject and describe particular FAA approved means of compliance with this AD.)

When the above modification is accomplished, compliance with the provisions of AD 61-21-02 is no longer required.

This directive effective November 23, 1961.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4A25](https://openairdocs.org/tcds/4A25): The Boeing Company; names 27 of 27 models: DC-8-41, DC-8-52, DC-8-61, DC-8-53, DC-8-51, DC-8-63, DC-8-11, DC-8-72F…

## 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: 8 (8 by airframe model, 0 by engine model)
- Makers: Douglas 5, Mcdonnell Douglas 3

Models with the most aircraft:

- [Douglas DC-8-73](https://openairdocs.org/model/douglas-dc-8-73): 2 aircraft (airframe model)
- [Douglas DC-8-73F](https://openairdocs.org/model/douglas-dc-8-73f): 2 aircraft (airframe model)
- [Mcdonnell Douglas DC-8-62](https://openairdocs.org/model/mcdonnell-douglas-dc-8-62): 1 aircraft (airframe model)
- [Mcdonnell Douglas DC-8-63](https://openairdocs.org/model/mcdonnell-douglas-dc-8-63): 1 aircraft (airframe model)
- [Mcdonnell Douglas DC-8-63F](https://openairdocs.org/model/mcdonnell-douglas-dc-8-63f): 1 aircraft (airframe model)
- [Douglas DC-8-72](https://openairdocs.org/model/douglas-dc-8-72): 1 aircraft (airframe model)

All 6 models: https://openairdocs.org/ad/61-24-03/models.md
Every aircraft: https://openairdocs.org/ad/61-24-03/aircraft.md

Its text cites no advisory circulars or STCs.

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