sensors Mode-S transponder

A591A4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N458UP · BOEING 757-200 · operated by UNITED PARCEL SERVICE CO

Hex
A591A4
Octal
51310644
Decimal
10,850,724
Country
US
Tail
N458UP
Type
B752
Broadcasting now · callsign UPS5806 · 2,450 ft
Flights observed
268
Distinct callsigns
20
Country
US
Last broadcast
5h ago

Current position

A591A4 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A591A4 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
UPS780 - 18 2026-06-27
UPS781 - 10 2026-06-30
UPS2320 - 8 2026-06-30
UPS996 - 7 2026-07-09
UPS705 United Parcel Service 7 2026-05-30
UPS1317 - 7 2026-07-01
UPS706 United Parcel Service 5 2026-05-29
UPS1468 - 5 2026-07-08
UPS991 - 4 2026-07-14
UPS9844 United Parcel Service 4 2026-04-23
UPS5062 United Parcel Service 4 2026-06-02
UPS402 United Parcel Service 4 2026-05-21
UPS1234 United Parcel Service 4 2026-05-19
UPS1233 United Parcel Service 4 2026-05-20
UPS1128 - 4 2026-07-07
UPS795 United Parcel Service 3 2026-05-29
UPS7818 United Parcel Service 3 2026-06-02
UPS403 United Parcel Service 3 2026-05-21
UPS2038 United Parcel Service 3 2026-05-12
UPS1467 - 3 2026-07-09

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 UPS2991 GEG → ONT Jul 14, 12:30 UTCJul 14, 14:40 UTC2h 10m
2026-07-14 UPS2991 GEG → ONT Jul 14, 12:34 UTCJul 14, 14:44 UTC2h 10m
2026-07-14 UPS992 - Jul 14, 09:25 UTCJul 14, 11:15 UTC1h 50m
2026-07-14 UPS992 ONT → GEG Jul 14, 09:25 UTCJul 14, 11:22 UTC1h 57m
2026-07-14 UPS991 - Jul 14, 03:55 UTCJul 14, 04:55 UTC1h 0m
2026-07-14 UPS991 - Jul 14, 02:35 UTCJul 14, 03:05 UTC30m
2026-07-14 UPS991 GEG → ONT Jul 14, 02:40 UTCJul 14, 04:42 UTC2h 2m
2026-07-11 UPS9821 - Jul 11, 11:40 UTCJul 11, 12:45 UTC1h 5m
2026-07-10 UPS598 - Jul 10, 08:55 UTCJul 10, 10:50 UTC1h 55m
2026-07-10 UPS598 ONT → BIL Jul 10, 08:57 UTCJul 10, 10:46 UTC1h 49m
2026-07-10 UPS991 GEG → ONT Jul 10, 02:35 UTCJul 10, 04:50 UTC2h 15m
2026-07-10 UPS2980 PDX → GEG Jul 10, 00:55 UTCJul 10, 01:40 UTC45m
2026-07-09 UPS2980 DFW → PDX Jul 9, 19:35 UTCJul 9, 23:15 UTC3h 40m
2026-07-09 UPS2977 PDX → DFW Jul 9, 12:30 UTCJul 9, 15:45 UTC3h 15m
2026-07-09 UPS2977 PDX → DFW Jul 9, 12:24 UTCJul 9, 15:36 UTC3h 12m
2026-07-09 UPS996 - Jul 9, 06:00 UTCJul 9, 10:25 UTC4h 25m
2026-07-09 UPS996 SDF → PDX Jul 9, 05:53 UTCJul 9, 10:21 UTC4h 28m
2026-07-09 UPS1467 - Jul 9, 02:40 UTCJul 9, 03:35 UTC55m
2026-07-09 UPS1467 SBN → SDF Jul 9, 02:38 UTCJul 9, 03:33 UTC55m
2026-07-08 UPS1468 - Jul 8, 10:35 UTCJul 8, 10:50 UTC15m
2026-07-08 UPS1468 FWA → SBN Jul 8, 10:31 UTCJul 8, 10:50 UTC19m
2026-07-08 UPS1468 - Jul 8, 09:10 UTCJul 8, 09:40 UTC30m
2026-07-08 UPS9602 ROA → SDF Jul 8, 04:15 UTCJul 8, 05:05 UTC50m
2026-07-08 UPS9602 ROA → SDF Jul 8, 04:12 UTCJul 8, 05:08 UTC56m
2026-07-08 UPS9328 - Jul 8, 02:30 UTCJul 8, 03:20 UTC50m
2026-07-07 UPS5299 - Jul 7, 11:40 UTCJul 7, 13:35 UTC1h 55m
2026-07-07 UPS5299 PVD → SDF Jul 7, 11:39 UTCJul 7, 13:36 UTC1h 57m
2026-07-07 UPS1128 SDF → PVD Jul 7, 08:20 UTCJul 7, 10:05 UTC1h 45m
2026-07-07 UPS1128 SDF → PVD Jul 7, 08:18 UTCJul 7, 10:04 UTC1h 46m
2026-07-07 UPS937 - Jul 7, 01:35 UTCJul 7, 05:00 UTC3h 25m
2026-07-07 UPS937 FAT → SDF Jul 7, 01:28 UTCJul 7, 05:05 UTC3h 37m
2026-07-05 UPS9787 - Jul 5, 12:25 UTCJul 5, 13:50 UTC1h 25m
2026-07-05 UPS9787 PDX → FAT Jul 5, 12:26 UTCJul 5, 14:02 UTC1h 36m
2026-07-03 UPS996 SDF → PDX Jul 3, 05:50 UTCJul 3, 10:00 UTC4h 10m
2026-07-03 UPS996 SDF → PDX Jul 3, 05:46 UTCJul 3, 09:57 UTC4h 11m
2026-07-03 UPS1467 - Jul 3, 02:50 UTCJul 3, 03:35 UTC45m
2026-07-02 UPS1468 FWA → SBN Jul 2, 10:59 UTCJul 2, 11:19 UTC20m
2026-07-02 UPS1468 - Jul 2, 08:55 UTCJul 2, 09:25 UTC30m
2026-07-02 UPS9743 - Jul 2, 01:30 UTCJul 2, 03:25 UTC1h 55m
2026-07-02 UPS9743 MIA → SDF Jul 2, 01:33 UTCJul 2, 03:23 UTC1h 50m
2026-07-01 UPS5334 DFW → MIA Jul 1, 21:15 UTCJul 1, 23:35 UTC2h 20m
2026-07-01 UPS5357 TPA → DFW Jul 1, 11:50 UTCJul 1, 14:10 UTC2h 20m
2026-07-01 UPS5357 TPA → DFW Jul 1, 11:47 UTCJul 1, 14:13 UTC2h 26m
2026-07-01 UPS1352 - Jul 1, 07:25 UTCJul 1, 09:20 UTC1h 55m
2026-07-01 UPS1352 PHL → TPA Jul 1, 07:19 UTCJul 1, 09:21 UTC2h 2m
2026-07-01 UPS1317 - Jul 1, 01:15 UTCJul 1, 03:00 UTC1h 45m
2026-07-01 UPS1317 JAX → PHL Jul 1, 01:30 UTCJul 1, 02:58 UTC1h 28m
2026-06-30 UPS2320 - Jun 30, 19:25 UTCJun 30, 20:40 UTC1h 15m
2026-06-30 UPS2320 SDF → JAX Jun 30, 19:27 UTCJun 30, 20:44 UTC1h 17m
2026-06-30 UPS5337 - Jun 30, 11:45 UTCJun 30, 13:00 UTC1h 15m

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 N458UP page for operator, model, and routing details .

Mode-S A591A4 frequently asked

What is Mode-S code A591A4?
A591A4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N458UP.
Where is Mode-S A591A4 registered?
Mode-S code A591A4 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 A591A4 broadcasting right now?
Yes. Mode-S A591A4 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A591A4, octal 51310644, decimal 10,850,724.
What flights does A591A4 operate?
Mode-S A591A4 has broadcast 20 distinct callsigns, including UPS780, UPS781, UPS2320, UPS996, UPS705.