sensors Mode-S transponder

A4EFF1

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N417UP · BOEING 757-200 · operated by UNITED PARCEL SERVICE CO

Hex
A4EFF1
Octal
51167761
Decimal
10,809,329
Country
US
Tail
N417UP
Type
B752
No current signal · last broadcast 27d ago
Flights observed
60
Distinct callsigns
20
Country
US
Last broadcast
27d ago

Last known position

Most recent position reported by Mode-S A4EFF1.

Country allocation

The ICAO 24-bit address A4EFF1 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
2026-05-02 UPS9500 SAT → DFW May 2, 10:40 UTCMay 2, 13:00 UTC2h 20m
2026-05-02 UPS1375 TYS → SDF May 2, 03:30 UTCMay 2, 04:00 UTC30m
2026-05-02 UPS1375 TYS → SDF May 2, 03:29 UTCMay 2, 04:02 UTC33m
2026-05-01 UPS1376 SDF → TYS May 1, 08:50 UTCMay 1, 09:25 UTC35m
2026-05-01 UPS1376 SDF → TYS May 1, 08:52 UTCMay 1, 09:28 UTC36m
2026-04-30 UPS5793 LBB → SDF Apr 30, 12:25 UTCApr 30, 14:10 UTC1h 45m
2026-04-30 UPS776 DFW → IAH Apr 30, 08:35 UTCApr 30, 10:45 UTC2h 10m
2026-04-30 UPS1123 ALB → SDF Apr 30, 00:45 UTCApr 30, 02:30 UTC1h 45m
2026-04-29 UPS1124 SDF → ALB Apr 29, 09:00 UTCApr 29, 10:20 UTC1h 20m
2026-04-29 UPS1124 SDF → ALB Apr 29, 08:54 UTCApr 29, 10:21 UTC1h 27m
2026-04-29 UPS943 SJC → RFD Apr 29, 02:09 UTCApr 29, 05:50 UTC3h 40m
2026-04-28 UPS5996 SDF → MHR Apr 28, 19:40 UTCApr 29, 00:15 UTC4h 35m
2026-04-28 UPS5365 PNS → SDF Apr 28, 14:40 UTCApr 28, 16:10 UTC1h 30m
2026-04-28 UPS1364 SDF → PNS Apr 28, 11:50 UTCApr 28, 13:15 UTC1h 25m
2026-04-28 UPS913 SNA → SDF Apr 28, 02:30 UTCApr 28, 06:50 UTC4h 20m
2026-04-27 UPS7839 ONT → FAT Apr 27, 23:20 UTCApr 28, 00:30 UTC1h 10m
2026-04-26 UPS5942 SDF → OAK Apr 26, 20:05 UTCApr 27, 00:40 UTC4h 35m
2026-04-26 UPS3401 MIA → SDF Apr 26, 03:45 UTCApr 26, 05:45 UTC2h 0m
2026-04-26 UPS3401 MIA → SDF Apr 26, 03:46 UTCApr 26, 06:19 UTC2h 33m
2026-04-25 UPS4336 SDF → MIA Apr 25, 21:20 UTCApr 25, 23:20 UTC2h 0m
2026-04-25 UPS795 HRL → SAT Apr 25, 02:40 UTCApr 25, 05:10 UTC2h 30m
2026-04-25 UPS795 HRL → SAT Apr 25, 02:30 UTCApr 25, 04:56 UTC2h 26m
2026-04-24 UPS796 SDF → MEM Apr 24, 09:10 UTCApr 24, 11:25 UTC2h 15m
2026-04-24 UPS796 SDF → MEM Apr 24, 09:00 UTCApr 24, 11:33 UTC2h 33m
2026-04-24 UPS1299 PVD → SDF Apr 24, 01:20 UTCApr 24, 03:15 UTC1h 55m
2026-04-24 UPS1299 PVD → SDF Apr 24, 01:17 UTCApr 24, 03:13 UTC1h 56m
2026-04-23 UPS5062 SDF → BDL Apr 23, 22:05 UTCApr 23, 22:20 UTC15m
2026-04-23 UPS5062 SDF → BDL Apr 23, 19:25 UTCApr 23, 21:10 UTC1h 45m
2026-04-23 UPS2873 PHX → PHL Apr 23, 12:25 UTCApr 23, 14:45 UTC2h 20m
2026-04-23 UPS2873 PHX → PHL Apr 23, 12:25 UTCApr 23, 14:45 UTC2h 20m
2026-04-23 UPS872 SDF → ABQ Apr 23, 08:05 UTCApr 23, 10:35 UTC2h 30m
2026-04-23 UPS872 SDF → ABQ Apr 23, 07:57 UTCApr 23, 10:27 UTC2h 30m
2026-04-23 UPS937 FAT → SDF Apr 23, 01:35 UTCApr 23, 05:05 UTC3h 30m
2026-04-23 UPS937 FAT → SDF Apr 23, 01:27 UTCApr 23, 05:08 UTC3h 41m
2026-04-22 UPS938 ONT → FAT Apr 22, 07:55 UTCApr 22, 11:45 UTC3h 50m
2026-04-22 UPS938 ONT → FAT Apr 22, 07:59 UTCApr 22, 11:57 UTC3h 58m
2026-04-22 UPS1291 CAE → SDF Apr 22, 01:10 UTCApr 22, 02:15 UTC1h 5m
2026-04-22 UPS1291 CAE → SDF Apr 22, 01:13 UTCApr 22, 02:12 UTC59m
2026-04-21 UPS1198 PHL → CAE Apr 21, 07:20 UTCApr 21, 08:30 UTC1h 10m
2026-04-21 UPS1198 PHL → CAE Apr 21, 07:24 UTCApr 21, 08:31 UTC1h 7m
2026-04-21 UPS1233 ORF → PHL Apr 21, 01:50 UTCApr 21, 02:30 UTC40m
2026-04-21 UPS1233 ORF → PHL Apr 21, 01:44 UTCApr 21, 02:39 UTC55m
2026-04-21 UPS1233 ORF → PHL Apr 21, 00:25 UTCApr 21, 00:45 UTC20m
2026-04-20 UPS9724 SDF → MEM Apr 20, 22:30 UTCApr 20, 22:55 UTC25m
2026-04-20 UPS9724 SDF → MEM Apr 20, 22:22 UTCApr 20, 22:51 UTC29m
2026-04-19 UPS5236 SDF → RIC Apr 19, 21:48 UTCApr 19, 22:28 UTC40m
2026-04-19 UPS5236 SDF → RIC Apr 19, 21:30 UTCApr 19, 22:30 UTC1h 0m
2026-04-18 UPS871 ABQ → DEN Apr 18, 04:45 UTCApr 18, 05:20 UTC35m
2026-04-18 UPS871 ABQ → DEN Apr 18, 03:25 UTCApr 18, 05:20 UTC1h 55m
2026-04-18 UPS871 ABQ → DEN Apr 18, 02:51 UTCApr 18, 05:16 UTC2h 25m

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 N417UP page for operator, model, and routing details .

Mode-S A4EFF1 frequently asked

What is Mode-S code A4EFF1?
A4EFF1 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N417UP.
Where is Mode-S A4EFF1 registered?
Mode-S code A4EFF1 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 A4EFF1 broadcasting right now?
No active broadcast right now. Last signal was 27d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4EFF1, octal 51167761, decimal 10,809,329.
What flights does A4EFF1 operate?
Mode-S A4EFF1 has broadcast 20 distinct callsigns, including UPS871, UPS776, UPS5793, UPS1233, UPS9724.