# AD 88-21-05: Exhaust Systems (STC SA980NM)

- Type: Airworthiness directive
- Status: Current
- Products: Aerostar PA-60-600 (Aerostar 600), PA-60-601 (Aerostar 601), PA-60-601P (Aerostar 601P), PA-60-602P (Aerostar 602P) and PA-60-700P (Aerostar 700P)
- Effective: November 6, 1988
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-6039
- Registered aircraft: 57 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/688A03196B1ABB04862569AF00766D15.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/88-21-05

## The airworthiness directive

88-21-05 PIPER: Amendment 39-6039. Applies to PA-60 series (all serial numbers) airplanes certificated in any category modified per Machen, Inc., Supplemental Type Certification (STC) No. SA980NM.

NOTE: STC No. SA980NM pertains to installation of AVCO Lycoming Model TIO-and LTIO-540-J2BD engines.

Compliance: Required as indicated, unless previously accomplished.

To prevent a possible inflight engine fire, accomplish the following:

  (a) Within the next 50 hours time-in-service, after the effective date of this AD, and thereafter at every 100 hours time-in-service, inspect, and replace, as necessary, the exhaust systems on both engines in accordance with Machen, Inc. Service Bulletin (SB) No. 66- 018, dated June 5, 1987.

  (b) The repetitive inspections specified in paragraph (a) are no longer required when the exhaust system has been modified in accordance with Machen, Inc. SB 66-019, dated January 8, 1988.

  (c) Within the next 50 hours time-in-service, after the effective date of this AD, and thereafter at every 100 hours time-in-service, inspect, and replace as necessary the oil lines on both engines in accordance with Machen, Inc. SB 66-018, dated June 5, 1987.

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

  (e) An equivalent means of compliance with this AD may be used if approved by the Manager, Modification Branch, ANM-190S, FAA, Northwest Mountain Region, 17900 Pacific Highway South, C-68966, Seattle, Washington 98168.

All persons affected by this directive may obtain copies of the documents referred to herein upon request to Machen, Inc., South 3608 Davison Boulevard, Spokane, Washington 99204 or may examine these documents at the Office of the Assistant Chief Counsel, Room 1558, FAA, 601 East 12th Street, Kansas City, Missouri 64106.

This amendment, 39-6039, becomes effective on November 6, 1988.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A17WE](https://openairdocs.org/tcds/A17WE): Aerostar Aircraft Corporation; names 5 of 5 models: PA-60-601P (Aerostar 601P), PA-60-601 (Aerostar 601), PA-60-602P (Aerostar 602P), PA-60-600 (Aerostar 600), PA-60-700P (Aerostar 700P)

## 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: 57 (57 by airframe model, 0 by engine model)
- Makers: Piper 57

Models with the most aircraft:

- [Piper PA-60-602P](https://openairdocs.org/model/piper-pa-60-602p): 31 aircraft (airframe model)
- [Piper PA-60-700P](https://openairdocs.org/model/piper-pa-60-700p): 17 aircraft (airframe model)
- [Piper PA-60-601P](https://openairdocs.org/model/piper-pa-60-601p): 9 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/88-21-05/models.md
Every aircraft: https://openairdocs.org/ad/88-21-05/aircraft.md

Its text cites no advisory circulars or STCs.

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