# AD 88-20-01: Firewall Material

- Type: Airworthiness directive
- Status: Current
- Products: Textron A36, B36TC and F33A
- Effective: October 19, 1988
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-6017
- Registered aircraft: 3,641 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/823B9CDB7EFCCDF7862569B300529639.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/88-20-01

## The airworthiness directive

88-20-01 BEECH: Amendment 39-6017. Applies to the following airplanes certificated in any category:

MODEL SERIAL NUMBER F33A CE-1162 through CE-1223 A36 E-2383 through E-2405 E-2407 through E-2409 B36TC EA-468 through EA-470 EA-472 through EA-474

Compliance: Required within the next 100 hours time-in-service after the effective date of this AD, unless already accomplished.

To prevent a potential fire in the cabin, accomplish the following:

  (a) Remove the Mortell 931 sound deadener material from the aft side of the firewall in accordance with the instructions in Beech Service Bulletin Number 2249, dated April 1988.

  (b) Airplanes may be flown in accordance with FAR 21.197 to a location where this AD may be accomplished.

  (c) An equivalent means of compliance with this AD may be used if approved by the Manager, FAA, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; Telephone(316) 946-4400.

All persons affected by this directive may obtain copies of this document referred to herein upon request to Beech Aircraft Corporation, Commercial Service, Dept. 52, P.O. Box 85, Wichita, Kansas 67201-0085; or may examine this document at the FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106.

This amendment, 39-6017, becomes effective on October 19, 1988.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 3A15](https://openairdocs.org/tcds/3A15): Textron Aviation Inc.; names 3 of 27 models: B36TC, A36, F33A

## 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: 3,641 (3,641 by airframe model, 0 by engine model)
- Makers: Beech 3,110, Raytheon 530, Beech/Goedkerj L 1

Models with the most aircraft:

- [Beech A36](https://openairdocs.org/model/beech-a36): 1,907 aircraft (airframe model)
- [Beech F33A](https://openairdocs.org/model/beech-f33a): 978 aircraft (airframe model)
- [Raytheon A36](https://openairdocs.org/model/raytheon-a36): 448 aircraft (airframe model)
- [Beech B36TC](https://openairdocs.org/model/beech-b36tc): 225 aircraft (airframe model)
- [Raytheon B36TC](https://openairdocs.org/model/raytheon-b36tc): 82 aircraft (airframe model)
- [Beech/Goedkerj L A36](https://openairdocs.org/model/beech-goedkerj-l-a36): 1 aircraft (airframe model)

All 8 models: https://openairdocs.org/ad/88-20-01/models.md
Every aircraft: https://openairdocs.org/ad/88-20-01/aircraft.md

Its text cites no advisory circulars or STCs.

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