sensors Mode-S transponder

AA7F09

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N77579 · BOEING 737 MAX 9 · operated by UNITED AIRLINES INC

Hex
AA7F09
Octal
52477411
Decimal
11,173,641
Country
US
Tail
N77579
Type
B39M
Broadcasting now · callsign UAL1693 · 6,100 ft
Flights observed
9
Distinct callsigns
5
Country
US
Last broadcast
16h ago

Current position

AA7F09 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address AA7F09 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 5 distinct

Callsign Airline Flights Last seen
UAL1147 - 4 2026-04-13
UAL8140 - 2 2026-04-13
UAL635 - 1 2026-04-12
UAL1507 - 1 2026-04-14
UAL1387 - 1 2026-04-13

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-14 UAL1507 - Apr 14, 05:15 UTCApr 14, 05:40 UTC25m
2026-04-13 UAL1387 - Apr 13, 19:55 UTCApr 13, 20:10 UTC15m
2026-04-13 UAL1147 - Apr 13, 16:15 UTCApr 13, 18:20 UTC2h 5m
2026-04-13 UAL1147 - Apr 13, 15:50 UTCApr 13, 18:20 UTC2h 30m
2026-04-13 UAL1147 - Apr 13, 12:41 UTCApr 13, 18:17 UTC5h 36m
2026-04-13 UAL1147 - Apr 13, 12:41 UTCApr 13, 18:11 UTC5h 30m
2026-04-13 UAL8140 - Apr 13, 00:20 UTCApr 13, 02:00 UTC1h 40m
2026-04-12 UAL8140 - Apr 12, 23:55 UTCApr 13, 02:00 UTC2h 5m
2026-04-12 UAL635 - Apr 12, 17:20 UTCApr 12, 19:00 UTC1h 40m

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 N77579 page for operator, model, and routing details .

Mode-S AA7F09 frequently asked

What is Mode-S code AA7F09?
AA7F09 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N77579.
Where is Mode-S AA7F09 registered?
Mode-S code AA7F09 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 AA7F09 broadcasting right now?
Yes. Mode-S AA7F09 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AA7F09, octal 52477411, decimal 11,173,641.
What flights does AA7F09 operate?
Mode-S AA7F09 has broadcast 5 distinct callsigns, including UAL1147, UAL8140, UAL635, UAL1507, UAL1387.