Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A224F9

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N23707 · BOEING 737-700 · operated by UNITED AIRLINES INC

Hex
A224F9
Octal
50422371
Decimal
10,626,297
Country
US
Tail
N23707
Type
B737
No current signal · last broadcast Jul 26, 21:25 UTC
Flights observed
455
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 21:25 UTC

Last known position

Most recent position reported by Mode-S A224F9.

Country allocation

The ICAO 24-bit address A224F9 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
UAL1655 United Airlines 11 2026-05-19
UAL764 United Airlines 10 2026-05-19
UAL1559 - 9 2026-07-14
UAL1304 - 8 2026-07-14
UAL632 - 7 2026-07-16
UAL490 United Airlines 7 2026-06-03
UAL2344 - 7 2026-07-01
UAL1764 - 6 2026-07-16
UAL1477 - 6 2026-07-08
UAL1044 United Airlines 6 2026-04-17
UAL2186 United Airlines 5 2026-07-26
UAL2116 - 5 2026-07-15
UAL1709 - 5 2026-07-15
UAL1478 - 5 2026-06-26
UAL780 - 4 2026-07-15
UAL637 - 4 2026-07-01
UAL497 United Airlines 4 2026-05-07
UAL410 United Airlines 4 2026-05-07
UAL2800 United Airlines 4 2026-06-02
UAL2410 - 4 2026-07-16

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 UAL1884 EWR → RSW Jul 26, 19:45 UTCJul 26, 21:25 UTC1h 40m
2026-07-26 UAL1144 CUN → SFO Jul 26, 16:15 UTCJul 26, 18:30 UTC2h 15m
2026-07-26 UAL1144 CUN → SFO Jul 26, 16:11 UTCJul 26, 18:31 UTC2h 20m
2026-07-26 UAL1207 EWR → JAX Jul 26, 12:55 UTCJul 26, 14:50 UTC1h 55m
2026-07-26 UAL2186 EWR → MSY Jul 26, 04:30 UTCJul 26, 09:25 UTC4h 56m
2026-07-26 UAL2186 EWR → MSY Jul 26, 04:26 UTCJul 26, 09:22 UTC4h 56m
2026-07-25 UAL1690 EWR → PBI Jul 25, 21:30 UTCJul 26, 02:33 UTC5h 3m
2026-07-25 UAL1690 EWR → PBI Jul 25, 21:25 UTCJul 26, 02:15 UTC4h 50m
2026-07-25 UAL661 ORD → EWR Jul 25, 14:15 UTCJul 25, 19:05 UTC4h 50m
2026-07-25 UAL308 ATL → EWR Jul 25, 01:40 UTCJul 25, 05:20 UTC3h 40m
2026-07-24 UAL545 LIH → SFO Jul 24, 22:10 UTCJul 24, 23:05 UTC55m
2026-07-24 UAL1069 SFO → LAX Jul 24, 20:10 UTCJul 24, 20:55 UTC45m
2026-07-24 UAL1502 EWR → ORD Jul 24, 14:15 UTCJul 24, 16:50 UTC2h 35m
2026-07-24 UAL1502 EWR → ORD Jul 24, 14:16 UTCJul 24, 16:42 UTC2h 26m
2026-07-24 UAL1710 JAX → ORD Jul 24, 02:00 UTCJul 24, 04:50 UTC2h 50m
2026-07-23 UAL630 BUF → ORD Jul 23, 22:05 UTCJul 23, 23:50 UTC1h 45m
2026-07-23 UAL630 BUF → ORD Jul 23, 21:52 UTCJul 23, 23:33 UTC1h 41m
2026-07-23 UAL2485 ORD → DEN Jul 23, 19:20 UTCJul 23, 20:35 UTC1h 15m
2026-07-23 UAL1548 IAH → SFO Jul 23, 14:35 UTCJul 23, 17:40 UTC3h 5m
2026-07-22 UAL2612 EWR → PHX Jul 22, 22:45 UTCJul 23, 02:05 UTC3h 20m
2026-07-22 UAL2612 EWR → PHX Jul 22, 22:34 UTCJul 23, 03:05 UTC4h 31m
2026-07-22 UAL2174 IAD → BDL Jul 22, 19:20 UTCJul 22, 21:05 UTC1h 45m
2026-07-22 UAL1616 BNA → ORD Jul 22, 15:35 UTCJul 22, 17:30 UTC1h 55m
2026-07-22 UAL2468 - Jul 22, 12:50 UTCJul 22, 13:50 UTC1h 0m
2026-07-21 UAL3925 EWR → SFO Jul 21, 17:10 UTCJul 21, 21:10 UTC4h 0m
2026-07-21 UAL308 ATL → EWR Jul 21, 02:00 UTCJul 21, 05:45 UTC3h 45m
2026-07-20 UAL545 LIH → SFO Jul 20, 22:50 UTCJul 20, 23:45 UTC55m
2026-07-20 UAL545 LIH → SFO Jul 20, 22:32 UTCJul 20, 23:29 UTC57m
2026-07-20 UAL1069 SFO → LAX Jul 20, 20:25 UTCJul 20, 21:10 UTC45m
2026-07-20 UAL1069 SFO → LAX Jul 20, 20:21 UTCJul 20, 21:12 UTC51m
2026-07-20 UAL374 EWR → PBI Jul 20, 17:15 UTCJul 20, 18:50 UTC1h 35m
2026-07-20 UAL382 ORD → DCA Jul 20, 14:30 UTCJul 20, 16:00 UTC1h 30m
2026-07-19 UAL2072 EWR → ATL Jul 19, 22:30 UTCJul 20, 01:05 UTC2h 35m
2026-07-19 UAL2072 EWR → ATL Jul 19, 22:36 UTCJul 20, 00:53 UTC2h 17m
2026-07-19 UAL1955 IAD → PHX Jul 19, 18:20 UTCJul 19, 21:15 UTC2h 55m
2026-07-19 UAL2032 LAX → SFO Jul 19, 14:14 UTCJul 19, 16:07 UTC1h 53m
2026-07-18 UAL378 ORD → EWR Jul 18, 23:45 UTCJul 19, 16:30 UTC16h 45m
2026-07-18 UAL224 - Jul 18, 14:55 UTCJul 18, 22:15 UTC7h 20m
2026-07-18 UAL2684 PHL → ORD Jul 18, 11:25 UTCJul 18, 12:55 UTC1h 30m
2026-07-18 UAL1557 ORD → MDT Jul 18, 04:07 UTCJul 18, 05:25 UTC1h 18m
2026-07-18 UAL1557 - Jul 18, 04:10 UTCJul 18, 05:25 UTC1h 15m
2026-07-18 UAL1316 - Jul 18, 00:04 UTCJul 18, 02:25 UTC2h 20m
2026-07-17 UAL1316 SAT → ORD Jul 17, 23:57 UTCJul 18, 02:18 UTC2h 21m
2026-07-17 UAL2844 - Jul 17, 19:30 UTCJul 17, 21:44 UTC2h 15m
2026-07-17 UAL1502 - Jul 17, 14:44 UTCJul 17, 17:30 UTC2h 45m
2026-07-16 UAL2410 IAD → SLC Jul 16, 23:59 UTCJul 17, 03:50 UTC3h 50m
2026-07-16 UAL1764 - Jul 16, 19:40 UTCJul 16, 20:39 UTC1h 0m
2026-07-16 UAL632 - Jul 16, 17:05 UTCJul 16, 18:00 UTC55m
2026-07-16 UAL2639 DFW → IAD Jul 16, 12:44 UTCJul 16, 15:19 UTC2h 35m
2026-07-15 UAL2116 IAD → DFW Jul 15, 22:40 UTCJul 16, 01:20 UTC2h 40m

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 N23707 page for operator, model, and routing details .

Mode-S A224F9 frequently asked

What is Mode-S code A224F9?
A224F9 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N23707.
Where is Mode-S A224F9 registered?
Mode-S code A224F9 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 A224F9 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:25 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A224F9, octal 50422371, decimal 10,626,297.
What flights does A224F9 operate?
Mode-S A224F9 has broadcast 20 distinct callsigns, including UAL1655, UAL764, UAL1559, UAL1304, UAL632.