# AD 79-05-11: Engine Power Control Loss

- Type: Airworthiness directive
- Status: Current
- Products: Piper PA-44-180
- Effective: March 15, 1979
- Published: March 8, 1979
- Issued: February 27, 1979
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-3433
- Registered aircraft: 562 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/FD87B96334FF631B8625699E004AEB7F.0001
- DRS record last changed: November 21, 2025
- Page: https://openairdocs.org/ad/79-05-11

## The airworthiness directive

79-05-11 PIPER AIRCRAFT CORPORATION: Amendment 39-3433. Applies to Model PA-44-180, serial numbers 44-7995001 through 44-7995144, 44-7995146 through 44-7995180, 44-7995182 through 44-7995186, 44-7995190, 44-7995192, 44-7995193, 44-7995195, and 44-7995197 airplanes certificated in all categories.

Compliance is required within the next 10 hours' time in service after the effective date of this AD, unless already accomplished.

To prevent loss of engine power control due to a damaged or binding throttle control cable or restricted carburetor throttle arm movement, on both engines, accomplish the following:

  (a) Remove upper and lower cowling.

  (b) Disconnect the throttle cable at the carburetor end and inspect the throttle control cable movement for full and free travel. If the throttle control cable movement exhibits stiffness or binding, replace the cable assembly with a serviceable unit.

  (c) Inspect the carburetor throttle arm movement for full and free travel. If the throttle arm movement exhibits stiffness or restricted movement, take the necessary corrective action.

NOTE: Marvel-Schebler/Tillotson Service Bulletin A2-78, dated October 1978, pertains to this condition.

  (d) Remove both left and right engine throttle control supports, and modify the part as shown in Figure No. 1 (dimensions are in inches). Re-mark the modified part as Part No. 86574-04.

  (e) Reinstall the modified support as shown in Figure No. 1 (dimensions are in inches). Apply torque in accordance with the Piper Maintenance Manual.

  (f) Re-rig the throttles in accordance with Figures No. 2 and No. 3 (dimensions are in inches).

  (g) Reinstall upper and lower cowling.

  (h) Adjust the throttle quadrant gear warning micro switch in accordance with Piper's Maintenance Manual.

    (i) Make an appropriate maintenance record entry.

  (j) An equivalent method of compliance may be approved by the Chief, Engineering and Manufacturing Branch, Federal Aviation Administration, Southern Region.

NOTE: Piper Service Bulletin 639, dated January 10, 1979, pertains to this subject.

This amendment becomes effective March 15, 1979.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A19SO](https://openairdocs.org/tcds/A19SO): Piper Aircraft Inc.; names 1 of 2 models: PA-44-180

## 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: 562 (562 by airframe model, 0 by engine model)
- Makers: Piper 558, New Piper 4

Models with the most aircraft:

- [Piper PA-44-180](https://openairdocs.org/model/piper-pa-44-180): 558 aircraft (airframe model)
- [New Piper PA-44-180](https://openairdocs.org/model/new-piper-pa-44-180): 4 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/79-05-11/models.md
Every aircraft: https://openairdocs.org/ad/79-05-11/aircraft.md

Its text cites no advisory circulars or STCs.

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