sensors Mode-S transponder

A7F804

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N612UX · EMBRAER ERJ-170-200 (long wing) · operated by UNITED AIRLINES INC

Hex
A7F804
Octal
51774004
Decimal
11,008,004
Country
US
Tail
N612UX
Type
E75L
No current signal · last broadcast 1d ago
Flights observed
7
Distinct callsigns
4
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A7F804.

Country allocation

The ICAO 24-bit address A7F804 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 4 distinct

Callsign Airline Flights Last seen
SKW5632 SkyWest Airlines 3 2026-04-13
SKW5320 - 2 2026-04-13
SKW5621 SkyWest Airlines 1 2026-04-13
SKW5411 - 1 2026-04-13

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-13 SKW5632 SNA → SFO Apr 13, 21:35 UTCApr 13, 23:40 UTC2h 5m
2026-04-13 SKW5320 - Apr 13, 16:40 UTCApr 13, 19:25 UTC2h 45m
2026-04-13 SKW5621 IAH → SAF Apr 13, 14:02 UTCApr 13, 15:18 UTC1h 16m
2026-04-13 SKW5411 - Apr 13, 02:38 UTCApr 13, 03:24 UTC46m
2026-04-13 SKW5632 SNA → SFO Apr 13, 00:20 UTCApr 13, 00:45 UTC25m
2026-04-12 SKW5632 SNA → SFO Apr 12, 23:55 UTCApr 13, 00:45 UTC50m
2026-04-12 SKW5320 - Apr 12, 16:40 UTCApr 12, 19:37 UTC2h 57m

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 N612UX page for operator, model, and routing details .

Mode-S A7F804 frequently asked

What is Mode-S code A7F804?
A7F804 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N612UX.
Where is Mode-S A7F804 registered?
Mode-S code A7F804 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 A7F804 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 A7F804, octal 51774004, decimal 11,008,004.
What flights does A7F804 operate?
Mode-S A7F804 has broadcast 4 distinct callsigns, including SKW5632, SKW5320, SKW5621, SKW5411.