# AD 94-01-15: Bulb Seal

- 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: March 3, 1994
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-8797
- Docket: 93-NM-138-AD
- Registered aircraft: 63 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/100BCAEA74A9FAE4862569740072B702.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/94-01-15

## The airworthiness directive

94-01-15 BOEING: Amendment 39-8797. Docket 93-NM-138-AD.

Applicability: Model 747 series airplanes with a stretched upper deck, all line numbers up to and including line number 980; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent the bulb seal from coming off the fascia panels and being ingested into the turbofans of the escape systems on the stretched upper deck (SUD), which could impede the inflation of the escape slide during an emergency situation, accomplish the following:

  (a) Within 6 months after the effective date of this AD, install an aluminum seal retainer on the bulb seal attached to the fascia panel of the escape systems on the SUD, in accordance with Boeing Alert Service Bulletin 747-25A3056, dated July 12, 1993.

  (b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO). Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

  (c) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished.

  (d) The installation shall be done in accordance with Boeing Alert Service Bulletin 747-25A3056, dated July 12, 1993. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

  (e) This amendment becomes effective on March 3, 1994.

## 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/94-01-15/models.md
Every aircraft: https://openairdocs.org/ad/94-01-15/aircraft.md

Its text cites no advisory circulars or STCs.

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