# N818HP: 2013 Harrison John C HP-18

- Status: Valid registration
- Airframe: [Harrison John C HP-18](https://openairdocs.org/model/harrison-john-c-hp-18) (registry code 05623LK, 1 seats)
- Engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999)
- Serial number: 46
- Year built: 2013
- Type: Fixed wing single engine
- Engine type: Reciprocating
- Airworthiness: Experimental, amateur built
- Airworthiness date: January 12, 2014
- Certificate issued: February 23, 2004
- Expires: July 31, 2029
- Mode S code: AB27D1
- Registered owner: [Helgersen William A](https://openairdocs.org/faa-owner/HELGERSEN%20WILLIAM%20A)
- Location: [Mokena, IL](https://openairdocs.org/faa-place/IL/Mokena)
- Owner type: Individual
- Owner's area on the map: 41.5378° N, 87.8926° W: Placed by OpenAirDocs at the center of ZIP code 60448, within about 2 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=818HP
- Page: https://openairdocs.org/aircraft/N818HP

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 (Harrison John C HP-18)

None in force.

### Matched by engine (Amateur-built UNKNOWN ENG)

None in force.

## Information bulletins (advisory)

None matched.

## NTSB investigations

None matched to N818HP.

## FAA accident and incident reports

None matched to N818HP.

## 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.

## Related

- Other Harrison John C HP-18 aircraft: https://openairdocs.org/model/harrison-john-c-hp-18/aircraft.md
- The Amateur-built UNKNOWN ENG engine: https://openairdocs.org/engine/amateur-built-unknown-eng.md

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