# AD 70-18-04: Transmission Vertical Status

- Type: Airworthiness directive
- Status: Current
- Products: FH1100 Manufacturing 1100
- Effective: September 15, 1970
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-1075
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/2CDC53AEA93B05B986256A38005FBE68.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/70-18-04

## The airworthiness directive

70-18-04 FAIRCHILD HILLER HELICOPTERS: Amdt. 39-1075. Applies to 1100 series helicopters certificated in all categories.

Compliance required within the next 25 flight hours of the effective date of this A/D unless already accomplished.

To prevent failure of transmission vertical struts and mounts:

  (1) Strip epoxy paint from weld areas of transmission vertical struts and mounts P/N 24-28030-1 and -2 with commercial paint stripper.

  (2) With dye penetrant inspect weld areas for cracks.

  (3) Replace any cracked part prior to further flight.

  (4) Refinish stripped areas with two coats of zinc chromate.

  (5) Repeat above procedure at each succeeding 100 flight hours.

This amendment is effective September 15, 1970.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H2WE](https://openairdocs.org/tcds/H2WE): Air Space Design and Manufacturing LLC; names 1 of 2 models: 1100

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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