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Registered aircraft · FAA record as of October 2, 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 · all S10-VTs and related versions
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.

Records check free · 1 to understand · 4 clear

The public federal record on N5121, read the way a buyer, lender or insurer reads it: FAA registration, prior tail numbers keyed on the serial number, reuse of the tail number, recent registry filings, and the NTSB accident record under this and every earlier registration.

CLEARRegistration and identity

Valid registration to Mountain Stemme LLC, an LLC, certificate issued August 26, 2025, expires August 31, 2032. No fractional interest recorded. [1]

ATTENTIONAirworthiness certificate

No airworthiness certificate is on file. Usual for a newly registered aircraft, a project, or an aircraft that has not flown since a change of registration; ask for the certificate. [1]

CLEARPrior registrations of this airframe

No earlier tail number is recorded against serial 11-023 for this model in the deregistered file. [2]

CLEARTail number reuse

No other airframe has carried N5121 according to the deregistered file. [2]

NOTERecent registry documents

No bills of sale, loans or releases have reached the registry in recent weeks. The index covers only recent filings; older liens are in the records file. [3]

CLEARAccident and incident record

No NTSB investigation records located under N5121. CLEAR means the query ran and returned nothing, not that nothing ever happened. [4]

PENDINGTitle chain, liens and 337 forms

These live in the FAA aircraft records file (every document ever filed against the aircraft) and, for larger aircraft, the International Registry. Part of the full report.

PENDINGAirworthiness directives and utilization

AD compliance against the logbooks and flight-activity reconciliation are researched layers of the full report.

CLEAR the source was checked and shows no adverse findingATTENTION a fact a buyer or lender should understand, often routineNOTE context onlyPENDING covered by the full report
  1. FAA Releasable Aircraft Database, master file, file of October 2, 2026. registry.faa.gov/
  2. FAA deregistered aircraft file (part of the same download), file of October 2, 2026. registry.faa.gov/
  3. FAA document index: registry documents received in recent weeks, file of October 2, 2026. registry.faa.gov/
  4. NTSB aviation accident database (CAROL), records through August 27, 2026. data.ntsb.gov/carol-main-public/basic-search

This automated check reads the public federal record. Nothing here is a legal opinion, an appraisal or a statement about the aircraft's condition; a CLEAR line is a statement about the searched record, not the aircraft.

Source: FAA Civil Aviation Registry, Releasable Aircraft Database, October 2, 2026. See this record on the FAA site · This record as data