# AD 75-23-09: Nose Cargo Door Latch System

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 747-200C Series and 747-200F Series
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-2420
- Registered aircraft: 3 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/8EFEDD7BC989693F86256832005CA6FB.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/75-23-09

## The airworthiness directive

75-23-09 BOEING: Amendment 39-2420. Applies to all Boeing 747-200C and 747-200F series airplanes certificated in all categories. Compliance required as indicated. In addition to the door warning light procedures in Boeing B-747 Operations Manual Bulletin 74-13, the following procedures are required to provide assurance of latch system integrity. Before further flight, and thereafter following each nose cargo door operation, accomplish the following: A. Close door electrically or manually until each latch pin is extended and the green, latches closed, light is illuminated on the nose door control panel at the loadmaster's station. B. Pull and collar circuit breakers C1407/28V DC "control nose cargo door." Circuit breakers are located on the P15 panel on the right hand side of the electronics bay. Access to this area is either from the ground through the electronics bay hatch or through the main deck floor. Optional to pulling and collaring C1407 and C1572 circuit breakers, pull and collar C1629, C1630, C1631, C1632, C1633, and C1634 circuit breakers on the H122 cargo door power panel. C. Placard the nose door control panel H121 and the nose wheel well control panel P37, "POWER REMOVED PER AD - CIRCUIT BREAKERS C1407 AND C1572 PULLED:" If optional circuit breakers procedure is used, placard the H122 cargo door power panel, "POWER REMOVED - CIRCUIT BREAKERS PULLED." D. Verify that all 16 latches are closed for dispatch by noting that each latch pin is fully extended into the latch fitting, per Boeing B-747 Dispatch Deviation Procedures Guide, Document D6-33391, page 2.52.6B, View B. Boeing Service Bulletin 747-52-2117 will be released in the near future which will give instructions for the modification of the nose cargo door latch and lock system. Incorporation of this FAA approved modification will constitute terminating action under the inspection provisions of this AD. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5. U.S.C. 552 (a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. The documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington.

This amendment becomes effective upon publication in the Federal Register for all persons except those to whom it was made effective immediately by telegram dated October 23, 1975.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A20WE](https://openairdocs.org/tcds/A20WE): The Boeing Company; names 2 of 14 models: 747-200F Series, 747-200C Series

## 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: Boeing 3

Models with the most aircraft:

- [Boeing 747-251F](https://openairdocs.org/model/boeing-747-251f): 2 aircraft (airframe model)
- [Boeing 747-273C](https://openairdocs.org/model/boeing-747-273c): 1 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/75-23-09/models.md
Every aircraft: https://openairdocs.org/ad/75-23-09/aircraft.md

Its text cites no advisory circulars or STCs.

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