# AD 86-19-06: Air Ducts

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 737-300 Series
- Effective: October 2, 1986
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-5404
- Registered aircraft: 8 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/292A37A15ECBF376862568AA006B2518.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/86-19-06

## The airworthiness directive

86-19-06 BOEING: Amendment 39-5404. Applies to Boeing Model 737-300 airplanes listed in Boeing Service Bulletin 737-21-1085, dated February 14, 1986, certificated in any category. Compliance required within 180 days after the effective date of this amendment, unless already accomplished.

To ensure air ducts have adequate flammability characteristics accomplish the following:

A. Replace air ducts in accordance with Boeing Service Bulletin 737-21-1085, dated February 14, 1986, or later FAA-approved revisions.

B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.

C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD.

All persons affected by this directive who have not already received the applicable service bulletin from the manufacturer may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124-2207. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington.

This amendment becomes effective October 2, 1986.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A16WE](https://openairdocs.org/tcds/A16WE): The Boeing Company; names 1 of 17 models: 737-300 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: 8 (8 by airframe model, 0 by engine model)
- Makers: Boeing 8

Models with the most aircraft:

- [Boeing 737-300](https://openairdocs.org/model/boeing-737-300): 4 aircraft (airframe model)
- [Boeing 737-301](https://openairdocs.org/model/boeing-737-301): 1 aircraft (airframe model)
- [Boeing 737-306](https://openairdocs.org/model/boeing-737-306): 1 aircraft (airframe model)
- [Boeing 737-319](https://openairdocs.org/model/boeing-737-319): 1 aircraft (airframe model)
- [Boeing 737-330](https://openairdocs.org/model/boeing-737-330): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/86-19-06/models.md
Every aircraft: https://openairdocs.org/ad/86-19-06/aircraft.md

Its text cites no advisory circulars or STCs.

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