# AD 66-27-06: Right-Hand Elevator Torque Tubes

- Type: Airworthiness directive
- Status: Current
- Products: Allied Ag Cat Productions G-164 and G-164A
- Effective: December 16, 1975
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-2452
- Registered aircraft: 272 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C8413006E33FC74186256D500042A30E.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/66-27-06

## The airworthiness directive

66-27-06 GRUMMAN: Amdt. 39-296 is further amended by Amendment 39-2452. Applies to Models G-164 and G-164A Airplanes that have elevators with Serial Number 461 and Below.

Compliance required as indicated.

To prevent failure of the elevator torque tube due to cracks, accomplish the following:

  (a) For airplanes with 1,000 or more hours' time in service on April 22, 1966, comply with (d) within the next 25 hours' time in service after April 22, 1966, and at intervals not to exceed 100 hours' time in service from the last inspection until modified in accordance with (f).

  (b) For airplanes with 500 or more but less than 1,000 hours' time in service on April 22, 1966, comply with (d) within the next 100 hours' time in service after April 22, 1966, or before the accumulation of 1,025 hours' time in service whichever occurs first, and at intervals not to exceed 100 hours' time in service from the last inspection until modified in accordance with (f).

  (c) For airplanes with less than 500 hours' time in service on April 22, 1966, comply with (d) before the accumulation of 600 hours' time in service and at intervals not to exceed 100 hours' time in service from the last inspection until modified in accordance with (f).

  (d) Remove two inboard blind rivets that attach the elevator leading edge skin cover, to the right-hand elevator torque tube. Visually inspect the torque tube for cracks where inboard elevator rib, is welded to the torque tube and between the two inboard blind rivets. If no cracks are found, install new rivets before further flight. If cracks are found, comply with (f) before further flight.

  (e) Within the next 25 hours in service after the effective date of the amendment, unless already accomplished within the last 75 hours in service, visually inspect the lefthand elevator torque tube for cracks where the inboard rib is welded to the torque tube. This inspection must be repeated at intervals of 100 hours until the aircraft is altered in accordance with paragraph (f).

  (f) Modify torque tube in accordance with Grumman Model G-164 Alert Service Bulletin No. 33, dated March 8, 1966, or later FAA-approved revision, or an equivalent approved by an FAA Aircraft Engineering Division or Engineering and Manufacturing Branch.

This supersedes AD 66-11-01.

Amendment 39-296 was effective October 29, 1966.

This amendment, 39-2452 is effective December 16, 1975.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 1A16](https://openairdocs.org/tcds/1A16): Allied Ag Cat Productions Inc.; names 2 of 10 models: G-164, G-164A

## 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: 272 (272 by airframe model, 0 by engine model)
- Makers: Grumman Acft ENG Cor-Schweizer 150, Grumman 115, Grumman American Avn. 6, Schweizer 1

Models with the most aircraft:

- [Grumman Acft ENG Cor-Schweizer G-164A](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164a): 150 aircraft (airframe model)
- [Grumman G-164A](https://openairdocs.org/model/grumman-g-164a): 63 aircraft (airframe model)
- [Grumman G-164](https://openairdocs.org/model/grumman-g-164): 52 aircraft (airframe model)
- [Grumman American Avn. G-164](https://openairdocs.org/model/grumman-american-avn-g-164): 3 aircraft (airframe model)
- [Grumman American Avn. G-164A](https://openairdocs.org/model/grumman-american-avn-g-164a): 3 aircraft (airframe model)
- [Schweizer G164A](https://openairdocs.org/model/schweizer-g164a): 1 aircraft (airframe model)

All 6 models: https://openairdocs.org/ad/66-27-06/models.md
Every aircraft: https://openairdocs.org/ad/66-27-06/aircraft.md

Its text cites no advisory circulars or STCs.

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