# AD 72-17-01: Induction Air Box Valve

- Type: Airworthiness directive
- Status: Current
- Products: Piper PA-34-200
- Effective: April 26, 1973
- Published: April 23, 1973
- Issued: April 12, 1973
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-1625
- Registered aircraft: 172 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/928A09E2595FD4EC86256E1200498960.0001
- DRS record last changed: November 21, 2025
- Page: https://openairdocs.org/ad/72-17-01

## The airworthiness directive

72-17-01 PIPER: Amendment 39-1500 as amended by Amendment 39-1625. Applies to PA-34-200 airplanes, Serial Nos. 34-E4 and 34-7250001 through 34-7350074.

Compliance required as indicated.

To prevent the possibility of a power loss due to the failure of the induction air box valve, accomplish the following:

  (a) For those airplanes with 100 or more hours time in service on the effective date of this airworthiness directive unless already accomplished within the last 100 hours time in service comply with paragraph (c) within the next 10 hours time in service and thereafter at intervals not to exceed 100 hours time in service from the last inspection.

  (b) For those airplanes with less than 100 hours time in service on the effective date of this airworthiness directive, unless already accomplished, comply with paragraph (c) upon the accumulation of 100 hours time in service or within the next 10 hours, whichever is later, and thereafter at intervals not to exceed 100 hours time in service from the last inspection.

  (c) Remove the induction air box assembly from each engine and remove the valve assembly from the box assembly to permit a thorough visual inspection of the valve assembly. Inspect the valve assembly for any evidence of excessive wear or cracks in the areas where the shaft mates to the valve assembly.

  (d) If valve assemblies are found to contain worn, loose, or cracked parts, replace the affected parts with serviceable parts of the same part numbers or incorporate Piper Kit Number 760 722V before further flight.

  (e) Reassemble induction air boxes, install and rig in accordance with PA-34 service manual.

Piper Service Bulletin Number 358 dated August 2, 1972, pertains to this subject.

  (f) The requirements of this AD do not apply when Piper Kit Number 760 722V is incorporated. Piper Service Bulletin No. 374 dated February 16, 1973, pertains to this subject.

Amendment 39-1500 was effective August 17, 1972, andwas effective upon receipt for all recipients of the air mail letter dated August 4, 1972, which contained this amendment.

This amendment 39-1625 becomes effective April 26, 1973.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A7SO](https://openairdocs.org/tcds/A7SO): Piper Aircraft Inc.; names 1 of 5 models: PA-34-200 (Seneca)

## 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: 172 (172 by airframe model, 0 by engine model)
- Makers: Piper 172

Models with the most aircraft:

- [Piper PA-34-200](https://openairdocs.org/model/piper-pa-34-200): 172 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/72-17-01/models.md
Every aircraft: https://openairdocs.org/ad/72-17-01/aircraft.md

Its text cites no advisory circulars or STCs.

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