# N173FR: 2000 Flight Research FRI H58C

- Status: Valid registration
- Airframe: [Flight Research FRI H58C](https://openairdocs.org/model/flight-research-fri-h58c) (registry code 056051H, 4 seats)
- Engine: [Allison T63 series](https://openairdocs.org/engine/allison-t63-series) (registry code 03031)
- Data sheets: [TCDS E2SO](https://openairdocs.org/tcds/E2SO) (Continental Aerospace Technologies, Inc.) (OpenAirDocs)
- Serial number: FRI 004
- Year built: 2000
- Type: Rotorcraft
- Engine type: Turbo-shaft
- Airworthiness: Experimental, research and development
- Airworthiness date: March 31, 2018
- Certificate issued: May 25, 2023
- Expires: May 31, 2030
- Mode S code: A124DF
- Registered owner: [National Test Pilot School](https://openairdocs.org/faa-owner/NATIONAL%20TEST%20PILOT%20SCHOOL)
- Location: [Mojave, CA](https://openairdocs.org/faa-place/CA/Mojave)
- Owner type: Corporation
- Owner's area on the map: 35.0658° N, 118.2218° W: Placed by OpenAirDocs at the center of ZIP code 93501, 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=173FR
- Page: https://openairdocs.org/aircraft/N173FR

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. The registry lists only the engine series, so ADs for every Allison T63 model are included.

## ADs that may apply (OpenAirDocs): 1 in force

### Matched by airframe (Flight Research FRI H58C)

None in force.

### Matched by engine (Allison T63 series)

- [AD 2012-03-06](https://openairdocs.org/ad/2012-03-06): Fuel servo diaphragm · Continental Motors 6-260-A, 6-285-A, 6-285-B and 482 more. Effective Feb 24, 2012

## Information bulletins (advisory) (3 in force)

- [SAIB NE-16-13](https://openairdocs.org/saib/NE-16-13): Powerplant - Prohibited use of sealant. Issued Mar 8, 2016
- [SAIB NE-13-04](https://openairdocs.org/saib/NE-13-04): Continental Motors, Inc. (CMI) Connecting Rod Piston Pin Bushing Inspection. Issued Oct 31, 2012
- [SAIB NE-02-31](https://openairdocs.org/saib/NE-02-31): . Issued Jun 10, 2002

## NTSB investigations

None matched to N173FR.

## FAA accident and incident reports

None matched to N173FR.

## 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) (4)

Approved for this aircraft's airframe or engine model, in force first, then newest. The registry doesn't record which STCs an aircraft has; its records do.

### Approved for the engine (Allison T63 series)

- [STC SE03309CH](https://openairdocs.org/stc/SE03309CH): Installation of Engine Preheat Kit, p/n TSP6CYL-2927-115 for 115 volt application. Hartzell Propeller Inc. Lists T6-320-A
- [STC SE1780NM](https://openairdocs.org/stc/SE1780NM): Installation of Precise Flight standby vacuum system (SVS III). Precise Flight Inc. Lists T6-320-A
- [STC SE09513SC](https://openairdocs.org/stc/SE09513SC): Installation and usage of Exxon 20W50 Multigrade aircraft engine oil conforming to Exxon Oil Formulation WS-3013. Exxon Company USA. Lists T6-320-A
- [STC SE5879SW](https://openairdocs.org/stc/SE5879SW): Use of Phillips X/C II 20W-50 and25W-60 oil (OSS 55875) in all Avco reciprocating aircraft engines from 65 to 450 BHP. Phillips Petroleum Co. Lists T6-320-A

## Related

- Other Flight Research FRI H58C aircraft: https://openairdocs.org/model/flight-research-fri-h58c/aircraft.md
- The Allison T63 series engine: https://openairdocs.org/engine/allison-t63-series.md

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