sensors Mode-S transponder

A0AA7C

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N142DU · AIRBUS A220-100 · operated by DELTA AIR LINES INC

Hex
A0AA7C
Octal
50125174
Decimal
10,529,404
Country
US
Tail
N142DU
Type
BCS1
No current signal · last broadcast 23h ago
Flights observed
6
Distinct callsigns
3
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A0AA7C.

Country allocation

The ICAO 24-bit address A0AA7C 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 3 distinct

Callsign Airline Flights Last seen
DAL2910 - 4 2026-04-13
DAL2081 Delta Air Lines 1 2026-04-12
DAL1140 - 1 2026-04-12

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 DAL2910 - Apr 13, 23:20 UTCApr 13, 23:30 UTC10m
2026-04-13 DAL2910 - Apr 13, 21:42 UTCApr 13, 23:01 UTC1h 19m
2026-04-13 DAL2910 - Apr 13, 19:50 UTCApr 13, 20:30 UTC40m
2026-04-13 DAL2910 - Apr 13, 19:14 UTCApr 13, 20:29 UTC1h 15m
2026-04-12 DAL1140 - Apr 12, 23:55 UTCApr 13, 00:15 UTC20m
2026-04-12 DAL2081 SAV → MSP Apr 12, 17:15 UTCApr 12, 19:25 UTC2h 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 N142DU page for operator, model, and routing details .

Mode-S A0AA7C frequently asked

What is Mode-S code A0AA7C?
A0AA7C is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N142DU.
Where is Mode-S A0AA7C registered?
Mode-S code A0AA7C 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 A0AA7C broadcasting right now?
No active broadcast right now. Last signal was 23h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A0AA7C, octal 50125174, decimal 10,529,404.
What flights does A0AA7C operate?
Mode-S A0AA7C has broadcast 3 distinct callsigns, including DAL2910, DAL2081, DAL1140.