sensors Mode-S transponder

AAC2E2

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N79279 · BOEING 737-800 · operated by UNITED AIRLINES INC

Hex
AAC2E2
Octal
52541342
Decimal
11,191,010
Country
US
Tail
N79279
Type
B738
Broadcasting now · callsign UAL1208 · 36,000 ft
Flights observed
10
Distinct callsigns
7
Country
US
Last broadcast
23h ago

Current position

AAC2E2 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address AAC2E2 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 7 distinct

Callsign Airline Flights Last seen
UAL2625 - 2 2026-04-13
UAL2479 - 2 2026-04-13
UAL2243 United Airlines 2 2026-04-13
UAL8198 - 1 2026-04-13
UAL2865 - 1 2026-04-13
UAL2185 - 1 2026-04-12
UAL1588 United Airlines 1 2026-04-12

Recent flights last 10

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL8198 - Apr 13, 23:40 UTCApr 13, 23:45 UTC5m
2026-04-13 UAL2243 SFO → EUG Apr 13, 19:50 UTCApr 13, 21:35 UTC1h 45m
2026-04-13 UAL2243 SFO → EUG Apr 13, 19:25 UTCApr 13, 20:10 UTC45m
2026-04-13 UAL2625 - Apr 13, 16:15 UTCApr 13, 17:45 UTC1h 30m
2026-04-13 UAL2625 - Apr 13, 16:00 UTCApr 13, 16:15 UTC15m
2026-04-13 UAL2865 - Apr 13, 12:20 UTCApr 13, 14:00 UTC1h 40m
2026-04-13 UAL2479 - Apr 13, 03:55 UTCApr 13, 04:20 UTC25m
2026-04-13 UAL2479 - Apr 13, 02:00 UTCApr 13, 04:15 UTC2h 15m
2026-04-12 UAL1588 EWR → SAV Apr 12, 23:55 UTCApr 13, 00:15 UTC20m
2026-04-12 UAL2185 - Apr 12, 17:15 UTCApr 12, 19:35 UTC2h 20m

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 N79279 page for operator, model, and routing details .

Mode-S AAC2E2 frequently asked

What is Mode-S code AAC2E2?
AAC2E2 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N79279.
Where is Mode-S AAC2E2 registered?
Mode-S code AAC2E2 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 AAC2E2 broadcasting right now?
Yes. Mode-S AAC2E2 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AAC2E2, octal 52541342, decimal 11,191,010.
What flights does AAC2E2 operate?
Mode-S AAC2E2 has broadcast 7 distinct callsigns, including UAL2625, UAL2479, UAL2243, UAL8198, UAL2865.