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Registered aircraft · FAA record as of September 25, 2026
N421EF

Alexander Schleicher ASK 21

Valid Electric gliderColorado

N421EF is an Alexander Schleicher ASK 21, a glider with no engine, built in 2013. It has 2 seats. It is registered to Soaring Society Of Boulder, a corporation in Boulder, Colorado. The registration is valid: it was issued on October 23, 2014 and expires on October 31, 2027. It holds a standard airworthiness certificate for utility, dated August 29, 2013.

Alexander Schleicher: AS 33 ME

Aircraft

Maker
Alexander Schleicher (Germany)
FAA spelling: ALEXANDER SCHLEICHER GMBH & CO
Model
ASK 21
Serial number
21905
Type
Glider
Power
None · None NONE
Seats
2
Year built
2013
Transponder code
A4FFC0 (octal 51177700)

Registration

Status
Valid registration
Certificate issued
October 23, 2014
Expires
October 31, 2027
Last FAA action
March 24, 2023
Airworthiness
Standard · Utility · August 29, 2013
FAA region
Northwest Mountain
FAA record id
01129860

Owner as the FAA publishes it

Name
Soaring Society Of Boulder
Type
Corporation
Address
PO Box 17577
Boulder, CO 80308-0577

Owners can ask the FAA to withhold their name and address from public files. When they do, those fields are blank here as well. How that works.

Documents on file 0

No bills of sale, loans or other documents are indexed against this tail number.

Source: FAA Civil Aviation Registry, Releasable Aircraft Database, September 25, 2026. See this record on the FAA site · This record as data