# AD 57-09-01: Aileron Bellcrank Casting

- Type: Airworthiness directive
- Status: Current
- Products: Twin Commander 520, 560, 560-A and 680
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Registered aircraft: 36 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/CCE31DEAFC1119DA86256A38005BED3C.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/57-09-01

## The airworthiness directive

57-09-01 AERO COMMANDER: Applies to All Model 520 Aircraft, Serial Numbers 31 and Above, and to All Models 560, 560A and 680 Aircraft.

Compliance required not later than the next 3 hours of flight or May 15, 1957, whichever occurs first and at 100-hour intervals thereafter.

As a result of finding cracks in the aileron bellcrank casting in the vicinity of the aileron push-pull rod attach bolt, the following action is considered necessary unless already accomplished.

Inspect, using dye penetrant or fluorescent methods, all aileron bellcrank castings P/N 3510005 on bellcrank assembly P/N 4510004-401 and 402 for cracks in upper or lower lugs to which the aileron push-pull rod attaches. Remove rod to make the inspection, replace all castings found defective and reattach push-pull rod, making certain no clearance exists between casting lugs and rod-end bearing inner race before tightening bolt. Use shim washers to eliminate clearance. The 100-hour reinspection of casing P/N 3510005 may be discontinued upon installation of revised casting under development by Aero Design. (Aero Design Service Bulletin No. 41, dated April 19, 1957, provides a sketch of the part and defines the area to be inspected.)

This AD covers the same inspection required by CAA telegraphic instructions dated April 25, 1957.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 6A1](https://openairdocs.org/tcds/6A1): Twin Commander Aircraft LLC; names 3 of 9 models: 520, 560, 560A
- [TCDS 2A4](https://openairdocs.org/tcds/2A4): Twin Commander Aircraft LLC; names 1 of 21 models: 680

## 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: 36 (36 by airframe model, 0 by engine model)
- Makers: Aero Commander 36

Models with the most aircraft:

- [Aero Commander 520](https://openairdocs.org/model/aero-commander-520): 12 aircraft (airframe model)
- [Aero Commander 680](https://openairdocs.org/model/aero-commander-680): 12 aircraft (airframe model)
- [Aero Commander 560-A](https://openairdocs.org/model/aero-commander-560-a): 10 aircraft (airframe model)
- [Aero Commander 560](https://openairdocs.org/model/aero-commander-560): 2 aircraft (airframe model)

All 4 models: https://openairdocs.org/ad/57-09-01/models.md
Every aircraft: https://openairdocs.org/ad/57-09-01/aircraft.md

Its text cites no advisory circulars or STCs.

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