# AD 73-11-02: Main Landing Gear Support Structure

- Type: Airworthiness directive
- Status: Current
- Products: Piper PA-34-200
- Effective: December 3, 1973
- Published: December 4, 1973
- Issued: November 16, 1973
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-1747
- Registered aircraft: 172 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E7BF3FE95399A73B86256E1200498B7D.0001
- DRS record last changed: November 21, 2025
- Page: https://openairdocs.org/ad/73-11-02

## The airworthiness directive

73-11-02 PIPER: Amdt. 39-1639 as amended by Amendment 39-1649 is further amended by Amendment 39-1747. Applies to Model PA-34-200 airplanes Serial Numbers 34-E4 and 34-7250001 through 34-7450039 certificated in all categories.

Compliance required within the next 10 hours time in service after the effective date of this AD and thereafter at intervals not to exceed 10 hours time in service from the last inspection.

To detect weakening of the main landing gear support structure, accomplish the following:

  (a) Visually check both left and right wing lower surface skins for wrinkling immediately outboard of the wheel well openings.

  (b) If wrinkles are present, visually check the wing ribs located at the outer end of the wheel wells (wing station 69.24) for cracks and/or wrinkles in the web. These cracks or wrinkles emanate from the forward lower corner where the rib attaches to the main spar and may propagate toward the aft upper corner of the web.

  (c) If wrinkles are present and Aft Wing Modification Kit, Piper Part No. 760 696V, has not been installed, check the area where the main landing gear aft trunnion fitting attaches to the aft false spar for cracks.

  (d) If cracks or wrinkles are present in the areas described in (b) or (c), replace affected parts with serviceable parts of the same part number or make an FAA approved repair before further flight.

The checks required by paragraphs (a), (b) and (c) should also be accomplished after unusually fast and/or hard landings.

Piper Service Bulletin No. 369 pertains to this subject.

The initial inspection and repetitive inspections at 10 hours intervals are still required after compliance with Piper Service Bulletin No. 369, and/or after repair/replacement of the rib has been accomplished.

The checks required by paragraph (a) may be performed by the pilot.

When aft wing modification kit Piper Part No. 760 696V has been installed and the inspection and reservicing of the main landing gear oleo struts has been accomplished in accordance with the "Instructions" section of Piper Service Bulletin No. 406, the repetitive inspections in (a), (b), and (c) above are no longer necessary.

NOTE: Serial Numbers 34-7250023; 34-7250090; 34-7250203; 34-7250262; 34- 7250275; 34-7250282; 34-7250290; 34-7250296; 34-7250316; 34-7250317; 34-7250319; 34- 7250322; 34-7250325; 34-7250326; 34-7250328; 34-7250330; 34-7250331; 34-7250333; 34- 7250334; and 34-7250336 and up have had Piper Kit No. 760696V installed at the factory.

Amendment 39-1639 became effective May 21, 1973.

Amendment 39-1649 became effective May 31, 1973.

This Amendment 39-1747 becomes effective December 3, 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/73-11-02/models.md
Every aircraft: https://openairdocs.org/ad/73-11-02/aircraft.md

Its text cites no advisory circulars or STCs.

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