sensors Mode-S transponder

A1242D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N17289 · operated by UNITED AIRLINES INC

Hex
A1242D
Octal
50222055
Decimal
10,560,557
Country
US
Tail
N17289
Type
B38M
Broadcasting now · callsign UAL2650 · 50 ft
Flights observed
8
Distinct callsigns
5
Country
US
Last broadcast
1d ago

Current position

A1242D is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A1242D 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
UAL1419 United Airlines 3 2026-04-13
UAL2458 - 2 2026-04-13
UAL607 United Airlines 1 2026-04-13
UAL462 - 1 2026-04-12
UAL1429 United Airlines 1 2026-04-12

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL607 SJD → EWR Apr 13, 20:05 UTCApr 13, 23:30 UTC3h 25m
2026-04-13 UAL1419 CLE → FLL Apr 13, 12:20 UTCApr 13, 15:50 UTC3h 30m
2026-04-13 UAL1419 CLE → FLL Apr 13, 11:54 UTCApr 13, 17:17 UTC5h 23m
2026-04-13 UAL1419 CLE → FLL Apr 13, 11:45 UTCApr 13, 11:50 UTC5m
2026-04-13 UAL2458 - Apr 13, 00:20 UTCApr 13, 02:15 UTC1h 55m
2026-04-12 UAL2458 - Apr 12, 23:55 UTCApr 13, 02:15 UTC2h 20m
2026-04-12 UAL1429 IAH → EWR Apr 12, 19:55 UTCApr 12, 20:15 UTC20m
2026-04-12 UAL462 - Apr 12, 17:15 UTCApr 12, 18:20 UTC1h 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 N17289 page for operator, model, and routing details .

Mode-S A1242D frequently asked

What is Mode-S code A1242D?
A1242D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N17289.
Where is Mode-S A1242D registered?
Mode-S code A1242D 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 A1242D broadcasting right now?
Yes. Mode-S A1242D is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1242D, octal 50222055, decimal 10,560,557.
What flights does A1242D operate?
Mode-S A1242D has broadcast 5 distinct callsigns, including UAL1419, UAL2458, UAL607, UAL462, UAL1429.