# Underwood Harold THORP S-18

- Type: Aircraft model (FAA registry)
- Registry code: 0561434
- Manufacturer (registry): UNDERWOOD HAROLD
- Model: THORP S-18
- Aircraft type: Fixed wing single engine
- Category: Airplane
- Engines: 1 · Reciprocating
- Seats: 2
- Weight class: Up to 12,499 lb
- Certification: Not type certificated
- Registered aircraft: 1
- Page: https://openairdocs.org/model/underwood-harold-thorp-s-18

Model codes come from the FAA registry's reference file. ADs are matched to them by model name and maker.

## ADs that may apply (OpenAirDocs)

Matched to this model by model name and maker. Each AD's applicability may narrow it by serial number, part number or equipment.

None matched.

## Registered aircraft (1)

- [N444MA](https://openairdocs.org/aircraft/N444MA): [First Order Aeronautics LLC](https://openairdocs.org/faa-owner/FIRST%20ORDER%20AERONAUTICS%20LLC), [Lees Summit, MO](https://openairdocs.org/faa-place/MO/Lees%20Summit), built 2002, S/N 1HU

## NTSB investigations

None matched to aircraft with this model.

## FAA accident and incident reports

None matched to aircraft with this model.

## The same model under other registry codes

Amateur-built copies and renamed makers get their own codes.

- [Taylor Jeffrey Loren THORP S-18](https://openairdocs.org/model/taylor-jeffrey-loren-thorp-s-18): 1 registered aircraft, registry code 05605CJ
- [Williams William F THORP S-18](https://openairdocs.org/model/williams-william-f-thorp-s-18): 1 registered aircraft, registry code 05620TU
- [Copland George V THORP S-18](https://openairdocs.org/model/copland-george-v-thorp-s-18): 1 registered aircraft, registry code 89510R5
- [Mcclendon Joseph THORP S-18](https://openairdocs.org/model/mcclendon-joseph-thorp-s-18): 0 registered aircraft, registry code 056157M
- [Darby Erwin A/Darby Jean M THORP S 18](https://openairdocs.org/model/darby-erwin-a-darby-jean-m-thorp-s-18): 0 registered aircraft, registry code 05626AG

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