sensors Mode-S transponder

A12991

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N174RS · FLEET 7 · operated by RICCI MORETTI LUIGI U

Hex
A12991
Octal
50224621
Decimal
10,561,937
Country
US
Tail
N174RS
Type
FLE7
No current signal · last broadcast 1d ago
Flights observed
9
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A12991.

Country allocation

The ICAO 24-bit address A12991 falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 1 distinct

Callsign Airline Flights Last seen
N174RS - 9 2026-07-20

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-07-20 N174RS - Jul 20, 14:05 UTCJul 20, 14:15 UTC10m
2026-07-20 N174RS - Jul 20, 11:45 UTCJul 20, 13:00 UTC1h 15m
2026-07-19 N174RS - Jul 19, 22:05 UTCJul 19, 23:20 UTC1h 15m
2026-07-19 N174RS - Jul 19, 16:40 UTCJul 19, 17:55 UTC1h 15m
2026-07-19 N174RS - Jul 19, 14:15 UTCJul 19, 15:40 UTC1h 25m
2026-07-17 N174RS - Jul 17, 16:44 UTCJul 17, 17:05 UTC20m
2026-07-16 N174RS - Jul 16, 16:05 UTCJul 16, 16:19 UTC15m
2026-07-16 N174RS - Jul 16, 14:55 UTCJul 16, 15:05 UTC10m
2026-07-16 N174RS - Jul 16, 12:55 UTCJul 16, 14:05 UTC1h 10m

About Mode-S

A Mode-S transponder code (also called an "ICAO 24-bit address" or "hex code") is a 6-character hexadecimal identifier permanently assigned to an aircraft when it's first registered. Unlike callsigns (which change with each flight) or registrations (which can change if an aircraft is sold internationally), the Mode-S address stays with the airframe for the life of the aircraft in that country.

Every ADS-B transmission from an aircraft includes its Mode-S address, making it the most reliable way to identify a specific airframe. Flight-tracking services like Apparatus use the Mode-S address as the primary key for tying position broadcasts, callsigns, and ownership records together.

Prefer a tail-number view? See the N174RS page for operator, model, and routing details .

Mode-S A12991 frequently asked

What is Mode-S code A12991?
A12991 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N174RS.
Where is Mode-S A12991 registered?
Mode-S code A12991 is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A12991 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A12991, octal 50224621, decimal 10,561,937.
What flights does A12991 operate?
Mode-S A12991 has broadcast 1 distinct callsign, including N174RS.