# AD 74-12-03: Oxygen System

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC-8-61F, DC-8-62F and DC-8-63F
- Effective: June 6, 1974
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-1858
- Registered aircraft: 1 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/CD0825720A6302D6862569C9006EC48F.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/74-12-03

## The airworthiness directive

74-12-03 MCDONNELL DOUGLAS: Amendment 39-1858. Applies to DC-8-61F, -62F, -63F convertible freighter airplanes, certificated in all categories.

  (1) For all aircraft in the passenger configuration, within twenty-four (24) hours of receipt of this telegram, or prior to further flight, whichever occurs later, unless already accomplished within the last 50 hours, perform the passenger oxygen system leak check per paragraph 1(a) DACO Alert Service Bulletin A35-25 Revision A dated May 10, 1974, or later FAA-approved revisions. If the oxygen system does not pass the leak check, inspect, repair and replace worn piping as required, and replace broken and missing supports prior to next flight; repeat leak test per DACO A.S.B. A35-25 Revision A, paragraph 1(a). At intervals not to exceed 50 flight hours visually inspect for worn oxygen piping, replace as necessary, and conduct the leak test per DACO A.S.B. A35-25 Revision A, paragraph 1(a) until the modifications described by DACO A.S.B. A35-25 Revision A, paragraph 1(b) have been accomplished. Within 300 hours time in service after initial leak check, secure all oxygen piping, per DACO A.S.B. A35-25 Revision A, paragraph 1(b).

  (2) For aircraft in the full freighter configuration, prior to further flight after receipt of this telegram, close the oxygen hand shutoff valve on the passenger system and placard system inoperative until (1), above, is accomplished. Prior to conversion to passenger configuration, perform checks, repair, and modifications of (1) above. Paragraph 2, DACO A.S.B. A35-25 Revision A covers this subject.

This amendment becomes effective June 6, 1974, for all persons except those to whom it was made effective immediately by telegram dated May 11, 1974.

## 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-8-62F, DC-8-63F, DC-8-61F

## 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: 1 (1 by airframe model, 0 by engine model)
- Makers: Mcdonnell Douglas 1

Models with the most aircraft:

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

All 1 models: https://openairdocs.org/ad/74-12-03/models.md
Every aircraft: https://openairdocs.org/ad/74-12-03/aircraft.md

Its text cites no advisory circulars or STCs.

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