# N1021B: 1966 Learjet 23, registration cancelled 1971-12-08

- Type: Cancelled registration (FAA registry, deregistered aircraft)
- Cancelled: December 8, 1971
- Status when cancelled: Valid registration
- Airframe: [Learjet 23](https://openairdocs.org/model/learjet-23) (registry code 5170102)
- Data sheets: [TCDS A5CE](https://openairdocs.org/tcds/A5CE) (OpenAirDocs)
- Serial number: 086
- Year built: 1966
- Type of aircraft: Fixed wing multi engine
- Certificate issued: April 23, 1967
- Mode S code: A00E9F
- Owner when cancelled: [Mack Trucks Inc](https://openairdocs.org/faa-owner/MACK%20TRUCKS%20INC)
- Location: [Allentown, PA](https://openairdocs.org/faa-place/PA/Allentown)
- Owner type: Corporation
- Owner's area on the map: 40.5936° N, 75.4784° W: Placed by OpenAirDocs: center of Allentown, PA, within about 2 miles (OpenAirDocs). The owner's mailing address, not where the aircraft was based
- The mark today: https://openairdocs.org/aircraft/N1021B
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=1021B
- Page: https://openairdocs.org/deregistered/N1021B-1971-12-08

From the FAA registry file of November 5, 2026, cancelled registrations. Owners' street addresses are left out. The Mode S code belongs to the N-number, not the airframe.

ADs and bulletins for the Learjet 23: https://openairdocs.org/model/learjet-23.md

## NTSB investigations (1)

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 CHI70A0027](https://openairdocs.org/ntsb/CHI70A0027), Nov 6, 1969: Lear Jet 23A (N1021B), Racine, WI, destroyed, 7 fatal

## Other aircraft with N1021B

- [Registered now](https://openairdocs.org/aircraft/N1021B): Air Tractor AT-502, S/N 502-0062, built 1989
- [Cancelled 1965-08-16](https://openairdocs.org/deregistered/N1021B-1965-08-16): Beech A45, S/N G-794

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