# AD 87-24-02: Longeron Fittings

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 747-100 Series, 747-100B Series, 747-100B SUD Series, 747-200B Series, 747-200C Series, 747-200F Series, 747-300 Series, 747-400 Series, 747-400D Series, 747-400F Series, 747SP Series and 747SR Series
- Effective: December 24, 1987
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-5768
- Registered aircraft: 63 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/AA950C449C7EF7AD8625695900728BEC.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/87-24-02

## The airworthiness directive

87-24-02 BOEING: Amendment 39-5768. Applies to Model 747 series airplanes, as listed in Boeing Alert Service Bulletin 747-53A2280, dated April 16, 1987, certificated in any category. Compliance required as indicated, unless previously accomplished.

To detect cracking of the body station (BS) 2598 longeron skin splice fittings and breakage of the tension bolts common to the fittings, accomplish the following:

A. Prior to the accumulation of 10,000 landings, or within 500 landings after the effective date of this AD, whichever occurs later, perform a detailed visual inspection of BS 2598 longeron skin splice fittings for cracking, and tension bolts common to these fittings for breakage, in accordance with Boeing Alert Service Bulletin 747-53A2280, dated April 16, 1987, or later FAA-approved revision. Reinspect the splice fittings and tension bolts common to stringer 11 longeron at intervals not to exceed 2,000 landings; and reinspect the splice fitting and tension bolts common to stringer 23 longeron at intervals not to exceed 4,000 landings.

B. If any longeron skin splice fitting is cracked, prior to further flight replace the fitting and the tension bolt common to that fitting, in accordance with Boeing Alert Service Bulletin 747-53A2280, dated April 16, 1987, or later FAA-approved revision.

C. If a tension bolt is broken, but the fitting to which it is common is not cracked, prior to further flight, replace the bolt in accordance with Boeing Alert Service Bulletin 747- 53A2280, dated April 16, 1987, or later FAA-approved revision. This constitutes terminating action for the requirement to inspect the tension bolt.

D. Prior to the accumulation of 10,000 landings on new (replaced) BS 2598 longeron skin splice fittings, perform a detailed visual inspection of the splice fittings for cracking, in accordance with Boeing Alert Service Bulletin 747-53A2280, dated April 16, 1987, or later FAA-approved revision. Reinspect the splice fittingscommon to stringer 11 longeron at intervals not to exceed 3,000 landings; and reinspect the splice fittings common to stringer 23 longeron at intervals not to exceed 6,000 landings. Replace cracked fittings prior to further flight, in accordance with the service bulletin.

E. An alternate means of compliance or adjustment of the compliance time, which provide an acceptable level of safety and which has the concurrence of an FAA Principal Maintenance Inspector, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.

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

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or Seattle Aircraft Certification Office, FAA, Northwest Mountain Region, 9010 East Marginal Way South, Seattle, Washington.

This amendment becomes effective December 24, 1987.

## 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 12 of 14 models: 747-100B Series, 747SP Series, 747-400D Series, 747-400F Series, 747-200B Series, 747-200F Series, 747-300 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: 63 (63 by airframe model, 0 by engine model)
- Makers: Boeing 63

Models with the most aircraft:

- [Boeing 747-446](https://openairdocs.org/model/boeing-747-446): 10 aircraft (airframe model)
- [Boeing 747-422](https://openairdocs.org/model/boeing-747-422): 8 aircraft (airframe model)
- [Boeing 747-412](https://openairdocs.org/model/boeing-747-412): 5 aircraft (airframe model)
- [Boeing 747-400F](https://openairdocs.org/model/boeing-747-400f): 4 aircraft (airframe model)
- [Boeing 747-409](https://openairdocs.org/model/boeing-747-409): 4 aircraft (airframe model)
- [Boeing 747-481F](https://openairdocs.org/model/boeing-747-481f): 3 aircraft (airframe model)
- [Boeing 747-409F](https://openairdocs.org/model/boeing-747-409f): 3 aircraft (airframe model)
- [Boeing 747-481](https://openairdocs.org/model/boeing-747-481): 3 aircraft (airframe model)
- [Boeing 747-428F](https://openairdocs.org/model/boeing-747-428f): 3 aircraft (airframe model)
- [Boeing 747-123](https://openairdocs.org/model/boeing-747-123): 2 aircraft (airframe model)
- [Boeing 747-251F](https://openairdocs.org/model/boeing-747-251f): 2 aircraft (airframe model)
- [Boeing 747-443](https://openairdocs.org/model/boeing-747-443): 2 aircraft (airframe model)
- [Boeing 747-438](https://openairdocs.org/model/boeing-747-438): 2 aircraft (airframe model)
- [Boeing 747-428](https://openairdocs.org/model/boeing-747-428): 2 aircraft (airframe model)
- [Boeing 747-257B](https://openairdocs.org/model/boeing-747-257b): 1 aircraft (airframe model)
- [Boeing 747-283B](https://openairdocs.org/model/boeing-747-283b): 1 aircraft (airframe model)
- [Boeing 747-121](https://openairdocs.org/model/boeing-747-121): 1 aircraft (airframe model)
- [Boeing 747-131](https://openairdocs.org/model/boeing-747-131): 1 aircraft (airframe model)
- [Boeing 747-128](https://openairdocs.org/model/boeing-747-128): 1 aircraft (airframe model)
- [Boeing 747-273C](https://openairdocs.org/model/boeing-747-273c): 1 aircraft (airframe model)

All 24 models: https://openairdocs.org/ad/87-24-02/models.md
Every aircraft: https://openairdocs.org/ad/87-24-02/aircraft.md

Its text cites no advisory circulars or STCs.

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