sensors Mode-S transponder

AA7F23

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N77580 · operated by UNITED AIRLINES INC

Hex
AA7F23
Octal
52477443
Decimal
11,173,667
Country
US
Tail
N77580
Type
B39M
Transponder active on ground
Flights observed
202
Distinct callsigns
20
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S AA7F23.

Country allocation

The ICAO 24-bit address AA7F23 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

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 UAL1400 SMF → ORD May 29, 20:35 UTCMay 29, 23:15 UTC2h 40m
2026-05-29 UAL2287 ORD → SAN May 29, 16:34 UTCMay 29, 18:43 UTC2h 9m
2026-05-29 UAL2287 ORD → SAN May 29, 16:30 UTCMay 29, 18:45 UTC2h 15m
2026-05-29 UAL1554 SJC → DEN May 29, 11:10 UTCMay 29, 13:50 UTC2h 40m
2026-05-28 UAL2618 IAD → SFO May 28, 21:59 UTCMay 29, 00:20 UTC2h 21m
2026-05-28 UAL2618 IAD → SFO May 28, 22:00 UTCMay 28, 22:45 UTC45m
2026-05-27 UAL1664 PUJ → ORD May 27, 20:55 UTCMay 27, 23:15 UTC2h 20m
2026-05-27 UAL1661 IAD → PUJ May 27, 13:30 UTCMay 27, 15:35 UTC2h 5m
2026-05-27 UAL1661 IAD → PUJ May 27, 13:04 UTCMay 27, 17:09 UTC4h 5m
2026-05-27 UAL1734 SAN → SFO May 27, 09:55 UTCMay 27, 11:05 UTC1h 10m
2026-05-27 UAL755 IAD → BOS May 27, 02:39 UTCMay 27, 04:04 UTC1h 25m
2026-05-26 UAL1648 AUA → IAD May 26, 20:45 UTCMay 27, 00:39 UTC3h 55m
2026-05-26 UAL1804 IAH → AUA May 26, 14:55 UTCMay 26, 19:05 UTC4h 10m
2026-05-26 UAL468 SFO → LAS May 26, 11:15 UTCMay 26, 13:10 UTC1h 55m
2026-05-25 UAL520 SFO → JFK May 25, 21:15 UTCMay 26, 02:19 UTC5h 5m
2026-05-25 UAL2017 IAH → BOS May 25, 14:10 UTCMay 25, 19:20 UTC5h 10m
2026-05-25 UAL1722 OGG → SFO May 25, 07:25 UTCMay 25, 12:20 UTC4h 55m
2026-05-25 UAL1722 OGG → SFO May 25, 07:22 UTCMay 25, 12:30 UTC5h 8m
2026-05-24 UAL2400 BOS → SFO May 24, 23:05 UTCMay 25, 05:00 UTC5h 55m
2026-05-24 UAL2400 BOS → SFO May 24, 22:57 UTCMay 25, 04:59 UTC6h 2m
2026-05-24 UAL2647 DCA → IAH May 24, 15:20 UTCMay 24, 21:00 UTC5h 40m
2026-05-24 UAL1947 LGA → IAH May 24, 02:05 UTCMay 24, 02:25 UTC20m
2026-05-24 UAL1947 LGA → IAH May 24, 02:08 UTCMay 24, 06:57 UTC4h 49m
2026-05-23 UAL1260 SNA → SFO May 23, 23:55 UTCMay 24, 00:15 UTC20m
2026-05-23 UAL1260 SNA → SFO May 23, 19:30 UTCMay 23, 20:00 UTC30m
2026-05-23 UAL1658 IAD → BDL May 23, 12:25 UTCMay 23, 18:05 UTC5h 40m
2026-05-23 UAL1230 YVR → SFO May 23, 05:20 UTCMay 23, 10:15 UTC4h 55m
2026-05-22 UAL440 DEN → LAX May 22, 21:25 UTCMay 23, 03:35 UTC6h 9m
2026-05-22 UAL440 DEN → LAX May 22, 21:10 UTCMay 23, 03:31 UTC6h 21m
2026-05-22 UAL1392 EWR → CLT May 22, 17:10 UTCMay 22, 18:15 UTC1h 5m
2026-05-22 UAL2066 ORD → PHL May 22, 14:55 UTCMay 22, 15:30 UTC35m
2026-05-22 UAL2112 JAX → EWR May 22, 12:50 UTCMay 22, 13:30 UTC40m
2026-05-22 UAL2024 SJU → IAD May 22, 00:35 UTCMay 22, 01:20 UTC45m
2026-05-21 UAL2024 SJU → IAD May 21, 22:10 UTCMay 21, 22:20 UTC10m
2026-05-21 UAL1192 IAH → SJU May 21, 20:45 UTCMay 21, 20:55 UTC10m
2026-05-21 UAL1192 IAH → SJU May 21, 17:00 UTCMay 21, 19:15 UTC2h 15m
2026-05-21 UAL1192 IAH → SJU May 21, 16:59 UTCMay 21, 21:05 UTC4h 6m
2026-05-21 UAL1467 DEN → EWR May 21, 12:25 UTCMay 21, 14:45 UTC2h 20m
2026-05-21 UAL1266 LAX → SAL May 21, 05:55 UTCMay 21, 10:10 UTC4h 15m
2026-05-21 UAL1427 MID → IAH May 21, 01:40 UTCMay 21, 02:35 UTC55m
2026-05-20 UAL1754 MSN → ORD May 20, 21:30 UTCMay 20, 22:30 UTC1h 0m
2026-05-20 UAL337 DEN → DFW May 20, 18:15 UTCMay 20, 20:25 UTC2h 10m
2026-05-20 UAL1800 SNA → IAH May 20, 13:35 UTCMay 20, 15:30 UTC1h 55m
2026-05-20 UAL2372 LGA → IAH May 20, 07:35 UTCMay 20, 10:35 UTC3h 0m
2026-05-20 UAL2372 LGA → IAH May 20, 07:32 UTCMay 20, 10:29 UTC2h 57m
2026-05-20 UAL2294 AUS → EWR May 20, 00:50 UTCMay 20, 05:45 UTC4h 56m
2026-05-19 UAL413 MCO → EWR May 19, 20:30 UTCMay 19, 22:30 UTC2h 0m
2026-05-19 UAL413 MCO → EWR May 19, 20:36 UTCMay 19, 22:16 UTC1h 40m
2026-05-19 UAL2206 SFO → LAX May 19, 17:05 UTCMay 19, 18:45 UTC1h 40m
2026-05-18 UAL1648 AUA → IAD May 18, 20:35 UTCMay 19, 00:40 UTC4h 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 N77580 page for operator, model, and routing details .

Mode-S AA7F23 frequently asked

What is Mode-S code AA7F23?
AA7F23 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N77580.
Where is Mode-S AA7F23 registered?
Mode-S code AA7F23 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 AA7F23 broadcasting right now?
Mode-S AA7F23 is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AA7F23, octal 52477443, decimal 11,173,667.
What flights does AA7F23 operate?
Mode-S AA7F23 has broadcast 20 distinct callsigns, including UAL2219, UAL1040, UAL389, UAL1699, UAL1698.