sensors Mode-S transponder

A2B7F5

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N27419 · BOEING 737 MAX 9 · operated by UNITED AIRLINES INC

Hex
A2B7F5
Octal
50533765
Decimal
10,663,925
Country
US
Tail
N27419
Type
B39M
Broadcasting now · callsign UAL780C · 32,000 ft
Flights observed
7
Distinct callsigns
5
Country
US
Last broadcast
17h ago

Current position

A2B7F5 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A2B7F5 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
UAL668 - 2 2026-04-13
UAL1556 - 2 2026-04-13
UAL601 United Airlines 1 2026-04-13
UAL515 - 1 2026-04-14
UAL393 - 1 2026-04-12

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-14 UAL515 - Apr 14, 05:15 UTCApr 14, 05:50 UTC35m
2026-04-13 UAL668 - Apr 13, 19:50 UTCApr 13, 23:45 UTC3h 55m
2026-04-13 UAL668 - Apr 13, 19:15 UTCApr 13, 20:05 UTC50m
2026-04-13 UAL1556 - Apr 13, 17:35 UTCApr 13, 17:45 UTC10m
2026-04-13 UAL1556 - Apr 13, 14:10 UTCApr 13, 14:45 UTC35m
2026-04-13 UAL601 BOS → EWR Apr 13, 10:30 UTCApr 13, 11:40 UTC1h 10m
2026-04-12 UAL393 - Apr 12, 17:15 UTCApr 12, 19:20 UTC2h 5m

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 N27419 page for operator, model, and routing details .

Mode-S A2B7F5 frequently asked

What is Mode-S code A2B7F5?
A2B7F5 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N27419.
Where is Mode-S A2B7F5 registered?
Mode-S code A2B7F5 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 A2B7F5 broadcasting right now?
Yes. Mode-S A2B7F5 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A2B7F5, octal 50533765, decimal 10,663,925.
What flights does A2B7F5 operate?
Mode-S A2B7F5 has broadcast 5 distinct callsigns, including UAL668, UAL1556, UAL601, UAL515, UAL393.