# AD 72-14-05: Engine Exhaust System Stacks

- Type: Airworthiness directive
- Status: Current
- Products: Piper PA-23-250, PA-23-250 (Navy UO-1) and PA-E23-250
- Effective: September 3, 1974
- Published: August 27, 1974
- Issued: August 20, 1974
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-1943
- Registered aircraft: 899 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/537BD2C67E2D5DE086256E12004988AC.0001
- DRS record last changed: November 21, 2025
- Page: https://openairdocs.org/ad/72-14-05

## The airworthiness directive

72-14-05 PIPER: Amendment 39-1480 as amended by Amendment 39-1943. Applies to PA-23-250 and PA-E23-250 series aircraft Serial Nos. 27-2505 and up equipped with non-supercharged engine and certificated in all categories.

Compliane required within the next 50 hours time in service after the effective date of this AD, unless already accomplished within the last 50 hours and thereafter at intervals not to exceed 100 hours.

a. For airplanes Serial Nos. 27-7304959 and up, and earlier serial numbered aircraft which have field replacements, equipped with exhaust stack assemblies P/N's 33419-2, -3, 33420-2, -3 and stack support kit No. 760702, visually inspect both engine exhaust system stacks, manifolds, support tubes and brackets, and the slip joint inside the alternate air heat shroud. Inspect for cracks, flaking, burning, distortion and exhaust gas leaks at flanges and joints. Parts found cracked, flaked, burned, distorted or which allow leakage must be replaced prior to further flight.

b. For airplanes Serial Nos. 27-2505 to 27-7304958 inclusive equipped with original type exhaust system configuration or field replacement components as listed under Piper Service Letter No. 533, Service Spares Letter No. SP-301 or Service Bulletin No. 319: Visually inspect in accordance with a. above and adjust and align ball joint stack assemblies and supports in accordance with Piper Service Bulletin No. 319 dated April 19, 1971 or later approved revision.

c. Equivalent inspections or modifications may be approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. Aircraft may be flown to a base where the maintenance required by this airworthiness directive may be performed as permitted by FAR's 21.197 and 21.199.

(Piper Service Spares Letter No. SP-301 dated November 11, 1969, and Service Bulletin No. 319 dated April 19, 1971, pertain to this subject)

Amendment 39-1480 supersedes AD 69-23-01.

Amendment 39-1480 was effective July 12, 1972.

This Amendment 39-1943 is effective September 3, 1974.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 1A10](https://openairdocs.org/tcds/1A10): Piper Aircraft Inc.; names 2 of 6 models: PA-E23-250, PA-23-250 (Navy UO-1)

## 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: 899 (899 by airframe model, 0 by engine model)
- Makers: Piper 899

Models with the most aircraft:

- [Piper PA-23-250](https://openairdocs.org/model/piper-pa-23-250): 894 aircraft (airframe model)
- [Piper PA-23-250 (6PCLM)](https://openairdocs.org/model/piper-pa-23-250-6pclm): 5 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/72-14-05/models.md
Every aircraft: https://openairdocs.org/ad/72-14-05/aircraft.md

Its text cites no advisory circulars or STCs.

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