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Registered aircraft · FAA record as of September 25, 2026
N5121

Stemme Gmbh & Co S10-VT

Valid Colorado

N5121 is a Stemme Gmbh & Co S10-VT, a glider with a four-stroke engine. It has 2 seats. It is registered to Mountain Stemme LLC, an LLC in Boulder, Colorado. The registration is valid: it was issued on August 26, 2025 and expires on August 31, 2032. No airworthiness certificate is on file, which is normal for drones and for aircraft still being built or tested.

Aircraft

Maker
Stemme Gmbh & Co
Model
S10-VT
Serial number
11-023
Type
Glider
Power
Four-cycle piston, 1 motor
Seats
2
Year built
Not given
Transponder code
A66B58 (octal 51465530)

Registration

Status
Valid registration
Certificate issued
August 26, 2025
Expires
August 31, 2032
Last FAA action
August 26, 2025
Airworthiness
None on file
FAA region
Northwest Mountain
FAA record id
00085752

Owner as the FAA publishes it

Name
Mountain Stemme LLC
Type
LLC
Address
PO Box 17088
Boulder, CO 80308-0088

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