sensors Mode-S transponder

A0A900

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N14115 · BOEING 757-200 · operated by UNITED AIRLINES INC

Hex
A0A900
Octal
50124400
Decimal
10,529,024
Country
US
Tail
N14115
Type
B752
No current signal · last broadcast 1h ago
Flights observed
271
Distinct callsigns
20
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S A0A900.

Country allocation

The ICAO 24-bit address A0A900 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 20 distinct

Callsign Airline Flights Last seen
UAL311 United Airlines 14 2026-05-02
UAL119 United Airlines 13 2026-06-16
UAL118 United Airlines 12 2026-06-16
UAL310 United Airlines 11 2026-05-01
UAL978 United Airlines 8 2026-05-11
UAL351 - 8 2026-07-13
UAL350 - 8 2026-07-12
UAL228 United Airlines 8 2026-06-04
UAL979 United Airlines 7 2026-05-11
UAL316 United Airlines 6 2026-06-11
UAL239 - 6 2026-07-05
UAL229 United Airlines 6 2026-06-04
UAL913 - 5 2026-06-30
UAL912 United Airlines 5 2026-06-03
UAL2788 - 5 2026-07-03
UAL271 United Airlines 5 2026-06-19
UAL238 - 5 2026-07-05
UAL2127 - 5 2026-07-11
UAL145 United Airlines 5 2026-06-08
UAL634 - 4 2026-07-12

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 UAL1343 - Jul 14, 16:00 UTCJul 14, 21:25 UTC5h 25m
2026-07-14 UAL887 - Jul 14, 05:10 UTCJul 14, 12:30 UTC7h 20m
2026-07-13 UAL886 - Jul 13, 19:55 UTCJul 14, 02:50 UTC6h 55m
2026-07-13 UAL351 - Jul 13, 08:05 UTCJul 13, 16:10 UTC8h 5m
2026-07-12 UAL350 - Jul 12, 23:15 UTCJul 13, 06:05 UTC6h 50m
2026-07-12 UAL634 - Jul 12, 10:55 UTCJul 12, 11:45 UTC50m
2026-07-12 UAL634 BIO → EWR Jul 12, 10:53 UTCJul 12, 18:18 UTC7h 25m
2026-07-12 UAL634 BIO → EWR Jul 12, 10:53 UTCJul 12, 18:26 UTC7h 33m
2026-07-12 UAL633 EWR → BIO Jul 12, 01:40 UTCJul 12, 08:19 UTC6h 39m
2026-07-12 UAL633 - Jul 12, 01:45 UTCJul 12, 08:10 UTC6h 25m
2026-07-11 UAL2127 - Jul 11, 18:10 UTCJul 11, 23:20 UTC5h 10m
2026-07-10 UAL2191 - Jul 10, 18:30 UTCJul 11, 00:10 UTC5h 40m
2026-07-10 UAL37 - Jul 10, 09:30 UTCJul 10, 16:40 UTC7h 10m
2026-07-10 UAL36 - Jul 10, 01:25 UTCJul 10, 07:40 UTC6h 15m
2026-07-10 UAL36 EWR → EDI Jul 10, 01:05 UTCJul 10, 07:33 UTC6h 28m
2026-07-09 UAL1283 DEN → EWR Jul 9, 20:00 UTCJul 9, 23:10 UTC3h 10m
2026-07-09 UAL2308 - Jul 9, 09:40 UTCJul 9, 11:45 UTC2h 5m
2026-07-08 UAL2307 - Jul 8, 19:00 UTCJul 9, 02:00 UTC7h 0m
2026-07-07 UAL663 EWR → DEN Jul 7, 20:15 UTCJul 8, 00:30 UTC4h 15m
2026-07-07 UAL1403 - Jul 7, 13:15 UTCJul 7, 18:00 UTC4h 45m
2026-07-06 UAL2191 - Jul 6, 19:30 UTCJul 7, 00:30 UTC5h 0m
2026-07-06 UAL351 - Jul 6, 08:35 UTCJul 6, 16:35 UTC8h 0m
2026-07-05 UAL350 - Jul 5, 22:45 UTCJul 6, 05:35 UTC6h 50m
2026-07-05 UAL239 OPO → EWR Jul 5, 09:55 UTCJul 5, 17:00 UTC7h 5m
2026-07-05 UAL239 OPO → EWR Jul 5, 09:50 UTCJul 5, 16:56 UTC7h 6m
2026-07-05 UAL238 - Jul 5, 01:35 UTCJul 5, 02:00 UTC25m
2026-07-04 UAL238 EWR → OPO Jul 4, 23:48 UTCJul 5, 07:40 UTC7h 52m
2026-07-04 UAL2759 ORD → EWR Jul 4, 18:45 UTCJul 4, 20:20 UTC1h 35m
2026-07-04 UAL289 - Jul 4, 08:40 UTCJul 4, 16:15 UTC7h 35m
2026-07-04 UAL288 - Jul 4, 00:35 UTCJul 4, 06:55 UTC6h 20m
2026-07-03 UAL2788 EWR → ORD Jul 3, 20:23 UTCJul 3, 22:20 UTC1h 57m
2026-07-03 UAL2788 EWR → ORD Jul 3, 20:15 UTCJul 3, 22:40 UTC2h 25m
2026-07-03 UAL351 - Jul 3, 07:50 UTCJul 3, 16:00 UTC8h 10m
2026-07-02 UAL350 - Jul 2, 22:50 UTCJul 3, 05:45 UTC6h 55m
2026-07-02 UAL1149 EWR → SRQ Jul 2, 14:10 UTCJul 2, 19:00 UTC4h 50m
2026-07-01 UAL1340 - Jul 1, 23:10 UTCJul 2, 04:35 UTC5h 25m
2026-07-01 UAL634 ORD → CMH Jul 1, 11:05 UTCJul 1, 18:45 UTC7h 40m
2026-07-01 UAL633 - Jul 1, 01:35 UTCJul 1, 08:20 UTC6h 45m
2026-06-30 UAL1968 ORD → EWR Jun 30, 21:45 UTCJun 30, 23:20 UTC1h 35m
2026-06-30 UAL913 KEF → ORD Jun 30, 12:05 UTCJun 30, 18:15 UTC6h 10m
2026-06-30 UAL138 EWR → KEF Jun 30, 01:50 UTCJun 30, 06:55 UTC5h 5m
2026-06-29 UAL2127 - Jun 29, 17:34 UTCJun 29, 22:10 UTC4h 35m
2026-06-29 UAL2679 DEN → ORD Jun 29, 05:40 UTCJun 29, 11:10 UTC5h 30m
2026-06-28 UAL1700 - Jun 28, 23:25 UTCJun 29, 04:04 UTC4h 40m
2026-06-25 UAL2191 - Jun 25, 18:39 UTCJun 25, 23:59 UTC5h 20m
2026-06-25 UAL239 OPO → EWR Jun 25, 08:25 UTCJun 25, 15:33 UTC7h 8m
2026-06-25 UAL239 OPO → EWR Jun 25, 08:25 UTCJun 25, 15:24 UTC6h 59m
2026-06-25 UAL239 - Jun 25, 08:14 UTCJun 25, 08:50 UTC35m
2026-06-24 UAL238 EWR → OPO Jun 24, 23:24 UTCJun 25, 05:25 UTC6h 0m
2026-06-24 UAL37 - Jun 24, 08:55 UTCJun 24, 09:24 UTC30m

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 N14115 page for operator, model, and routing details .

Mode-S A0A900 frequently asked

What is Mode-S code A0A900?
A0A900 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N14115.
Where is Mode-S A0A900 registered?
Mode-S code A0A900 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 A0A900 broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A0A900, octal 50124400, decimal 10,529,024.
What flights does A0A900 operate?
Mode-S A0A900 has broadcast 20 distinct callsigns, including UAL311, UAL119, UAL118, UAL310, UAL978.