# N6638U: Hughes OH-6A

- Status: Valid registration
- Airframe: [Hughes OH-6A](https://openairdocs.org/model/hughes-oh-6a) (registry code 4470905, 4 seats)
- Data sheets: [TCDS H3WE](https://openairdocs.org/tcds/H3WE) (MD Helicopters LLC) (OpenAirDocs)
- Serial number: 6716030
- Type: Rotorcraft
- Engine type: Turbo-shaft
- Certificate issued: June 16, 2011
- Expires: June 30, 2027
- Mode S code: A8C2E1
- Registered owner: [Usda Aphis Ws Atoc](https://openairdocs.org/faa-owner/USDA%20APHIS%20WS%20ATOC)
- Location: [Cedar City, UT](https://openairdocs.org/faa-place/UT/Cedar%20City)
- Owner type: Government
- Owner's area on the map: 37.7687° N, 113.1336° W: Placed by OpenAirDocs at the center of ZIP code 84721, within about 8 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=6638U
- Page: https://openairdocs.org/aircraft/N6638U

From the FAA registry file of October 24, 2026. ADs below are matched by the registry's airframe and engine model codes. They may apply; each AD's applicability can narrow it by serial number, part number or installed equipment. This is not a compliance determination.

## ADs that may apply (OpenAirDocs): 0 in force

### Matched by airframe (Hughes OH-6A)

None in force.

## Information bulletins (advisory)

None matched.

## NTSB investigations

None matched to N6638U.

## NTSB investigations on N6638U not matched to an aircraft (2)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB MIA79FKG66](https://openairdocs.org/ntsb/MIA79FKG66), Aug 31, 1979: Mooney M20D (N6638U), Atlanta, GA, substantial damage
- [NTSB LAX65F0074](https://openairdocs.org/ntsb/LAX65F0074), Apr 10, 1965: Mooney M20D (N6638U), Van Nuys, CA, substantial damage

## FAA accident and incident reports

None matched to N6638U.

## Reports on N6638U not matched to an aircraft (1)

They name N6638U, but no registry record covers the date, the aircraft registered then was built later, or the report describes another aircraft.

- [Accident 19790831029859A](https://openairdocs.org/incident/19790831029859A), Aug 31, 1979: Mooney M20D (N6638U), Chamblee, GA, Substantial damage. Pilot reported engine failed over apt. Landed long on downwind rwy. Ran off rwy into trees. No engine defects noted

## Service difficulty reports

None filed for this aircraft. Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model.

## STCs that may be installed (OpenAirDocs)

None matched to this aircraft's models.

## Earlier aircraft with N6638U

The FAA can reassign an N-number once a registration is cancelled. These aircraft carried N6638U before.

- [Cancelled (date not recorded)](https://openairdocs.org/deregistered/N6638U-undated): Mooney M20D, S/N 133

## Related

- Other Hughes OH-6A aircraft: https://openairdocs.org/model/hughes-oh-6a/aircraft.md

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