# AD 84-09-04: Engine Thrust Reversers

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC-8-71, DC-8-72 and DC-8-73
- Effective: June 1, 1984
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-4855
- Registered aircraft: 3 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/8D0F36FB3E555BCA862569F2006A52F8.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/84-09-04

## The airworthiness directive

84-09-04 MCDONNELL DOUGLAS: Amendment 39-4855. Applies to McDonnell Douglas Model DC-8-70 series airplanes equipped with P/N C24466000 Thrust Reverser Hydraulic Control Units (HCU's) on the inboard thrust reversers, certificated in all categories.

Compliance required as indicated in the body of this AD, unless previously accomplished:

A. Replace P/N C24466000 HCU's on both inboard (#2 & #3) engine thrust reversers with P/N C24466000-/-2, P/N C24466001-2, or other FAA approved units, within 30 days after the effective date of this AD. The AFM limitations required by AD 82-19-51 R1, Amendment 39-4714 may be removed after HCU's are replaced on all aircraft in each operator's fleet.

Note: P/N C24466000 HCU's can be modified to P/N C24466000-/-2 in accordance with CFMI Service Bulletin (CFM-56-2) 78-057, dated March 30, 1982, or later FAA approved revisions.

B. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region.

C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplanes to a base to comply with the requirements of this AD.

All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Director, Publications and Training, C1-750 (54-60). These documents also may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or at the Los Angeles Aircraft Certification Office, 4344 Donald Douglas Drive, Long Beach, California.

This supersedes Amendment 39-4714 (48 FR 40212), AD 82-19-51.

This amendment becomes effective June 1, 1984.

## 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 3 of 27 models: DC-8-73, DC-8-71, DC-8-72

## 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: 3 (3 by airframe model, 0 by engine model)
- Makers: 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-8-72](https://openairdocs.org/model/douglas-dc-8-72): 1 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/84-09-04/models.md
Every aircraft: https://openairdocs.org/ad/84-09-04/aircraft.md

Its text cites no advisory circulars or STCs.

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