# AD 85-21-03: Engine Modification

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC-8-71, DC-8-72 and DC-8-73
- Effective: November 4, 1985
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-5143
- Registered aircraft: 3 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/B288C5A0BB54C82F862569F2006B8C4A.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/85-21-03

## The airworthiness directive

85-21-03 McDONNELL DOUGLAS: Amendment 39-5143. Applies to McDonnell Douglas Model DC-8-71, -72, and -73 series airplanes certificated in any category. To minimize inflight shutdowns due to oil loss, accomplish the following unless previously accomplished:

A. Within eighteen (18) months, or three thousand (3,000) landings, whichever occurs earlier, after the effective date of this AD, modify at least one engine on each side of the airplane in accordance with paragraph B., below, and complete the modifications on all engines within thirty-six (36) months, or six thousand (6,000) landings, whichever occurs earlier after the effective date of this AD.

B. Accomplish the modification described in paragraph A., above, in accordance with McDonnell Douglas Service Bulletin 71-96, dated February 12, 1985, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region.

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

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

All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to the 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 4344 Donald Douglas Drive, Long Beach, California.

This amendment becomes effective November 4, 1985.

## 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/85-21-03/models.md
Every aircraft: https://openairdocs.org/ad/85-21-03/aircraft.md

Its text cites no advisory circulars or STCs.

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