N4021S is not currently registered. It was last assigned to an Ayres Corporation S2R-600 built in 1980. The FAA cancelled the registration on November 8, 2013 when the aircraft was exported to Guatemala. The last status on file was "valid registration". The number has been on and off the register 2 times.
N4021S is reserved by Boeing CO since August 2, 2019. Reservation type: Reserved to manufacturer, temporary number.
Ayres Corporation S2R-600 cancelled November 8, 2013
- Serial number
- 2561R
- Type
- Fixed-wing, single engine · Piston (reciprocating)
- Year built
- 1980
- Last status
- Valid registration
- Exported to
- Guatemala
- Certificate issued
- October 18, 2013
- Last FAA action
- October 18, 2013
- Last owner
- Aircraft Escrow & Title CO (Corporation)
Wilmington, DE - Airworthiness
- Restricted · Agriculture and pest control
Sikorsky S-61D cancelled May 23, 1972
- Serial number
- 61497
- Type
- Rotorcraft · Turboshaft
- Year built
- —
- Last status
- Valid registration
- Exported to
- Argentina
- Certificate issued
- May 1, 1972
- Last FAA action
- —
- Last owner
- Sikorsky Aircraft Division United Aircraft CORP (Corporation)
Stratford, CT - Airworthiness
- None on file
NTSB accident and incident record under N4021S
Aircraft on the NTSB record: Ayres Corporation S2R-600 · serial 2561R
Partial loss of engine power for undetermined reasons.
A tail number passes between aircraft over the years; match the serial number on the NTSB record against the airframe above. Source: NTSB aviation accident database, records through September 30, 2026.
Source: FAA Civil Aviation Registry, Releasable Aircraft Database, October 2, 2026. See this number on the FAA site