sensors Mode-S transponder

A251F0

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N249FE · BOEING 767-200 · operated by BOEING CO

Hex
A251F0
Octal
50450760
Decimal
10,637,808
Country
US
Tail
N249FE
Type
B762
No current signal · last broadcast 19h ago
Flights observed
109
Distinct callsigns
20
Country
US
Last broadcast
19h ago

Last known position

Most recent position reported by Mode-S A251F0.

Country allocation

The ICAO 24-bit address A251F0 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
FDX51 FedEx Express 4 2026-05-17
FDX1443 FedEx Express 4 2026-04-28
FDX64 FedEx Express 3 2026-05-18
FDX568 FedEx Express 3 2026-04-17
FDX1874 FedEx Express 3 2026-04-29
FDX1684 FedEx Express 3 2026-05-29
FDX1552 FedEx Express 3 2026-05-27
FDX1545 FedEx Express 3 2026-04-16
FDX1346 FedEx Express 3 2026-05-28
FDX1200 FedEx Express 3 2026-05-21
FDX701 FedEx Express 2 2026-05-28
FDX630 FedEx Express 2 2026-05-13
FDX58 FedEx Express 2 2026-04-15
FDX476 FedEx Express 2 2026-04-14
FDX398 FedEx Express 2 2026-05-20
FDX382 FedEx Express 2 2026-05-12
FDX331 FedEx Express 2 2026-05-13
FDX257 FedEx Express 2 2026-04-14
FDX1738 - 2 2026-04-14
FDX1735 FedEx Express 2 2026-04-22

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 FDX1711 IND → DTW May 29, 08:35 UTCMay 29, 09:15 UTC40m
2026-05-29 FDX1684 FLL → IND May 29, 04:20 UTCMay 29, 06:25 UTC2h 5m
2026-05-28 FDX701 MEM → SDF May 28, 20:20 UTCMay 28, 22:15 UTC1h 55m
2026-05-28 FDX701 MEM → SDF May 28, 20:18 UTCMay 28, 22:15 UTC1h 57m
2026-05-28 FDX694 BWI → MEM May 28, 11:40 UTCMay 28, 13:20 UTC1h 40m
2026-05-28 FDX1434 MEM → IAD May 28, 08:10 UTCMay 28, 09:35 UTC1h 25m
2026-05-28 FDX1346 CLE → MEM May 28, 02:10 UTCMay 28, 03:35 UTC1h 25m
2026-05-27 FDX1552 MEM → CLE May 27, 09:20 UTCMay 27, 10:35 UTC1h 15m
2026-05-27 FDX1249 RDU → MEM May 27, 01:49 UTCMay 27, 03:14 UTC1h 25m
2026-05-22 FDX1449 MEM → RDU May 22, 08:50 UTCMay 22, 10:20 UTC1h 29m
2026-05-22 FDX1449 MEM → RDU May 22, 08:46 UTCMay 22, 10:15 UTC1h 29m
2026-05-22 FDX1240 LAS → MEM May 22, 02:30 UTCMay 22, 05:15 UTC2h 45m
2026-05-21 FDX1440 MEM → LAS May 21, 09:30 UTCMay 21, 12:30 UTC3h 0m
2026-05-21 FDX1200 FLL → MEM May 21, 02:50 UTCMay 21, 04:35 UTC1h 45m
2026-05-21 FDX1200 FLL → MEM May 21, 02:48 UTCMay 21, 04:41 UTC1h 53m
2026-05-20 FDX398 MEM → ORD May 20, 22:10 UTCMay 21, 00:05 UTC1h 55m
2026-05-20 FDX434 SAT → MEM May 20, 12:55 UTCMay 20, 14:10 UTC1h 15m
2026-05-20 FDX1426 MEM → JAX May 20, 10:00 UTCMay 20, 10:25 UTC25m
2026-05-20 FDX1426 MEM → JAX May 20, 07:25 UTCMay 20, 08:50 UTC1h 25m
2026-05-20 FDX1238 BUR → MEM May 20, 02:50 UTCMay 20, 04:15 UTC1h 25m
2026-05-20 FDX1238 BUR → MEM May 20, 02:48 UTCMay 20, 04:14 UTC1h 26m
2026-05-19 FDX1437 MEM → MKE May 19, 09:30 UTCMay 19, 10:45 UTC1h 15m
2026-05-18 FDX64 SJU → MEM May 18, 01:50 UTCMay 18, 06:01 UTC4h 10m
2026-05-17 FDX51 MEM → SJU May 17, 20:30 UTCMay 18, 00:00 UTC3h 30m
2026-05-17 FDX51 MEM → SJU May 17, 20:25 UTCMay 17, 23:59 UTC3h 34m
2026-05-15 FDX455 LAX → MEM May 15, 14:10 UTCMay 15, 17:15 UTC3h 4m
2026-05-15 FDX1438 MEM → ONT May 15, 08:25 UTCMay 15, 11:40 UTC3h 15m
2026-05-15 FDX1200 FLL → MEM May 15, 02:40 UTCMay 15, 04:35 UTC1h 55m
2026-05-14 FDX398 MEM → ORD May 14, 22:05 UTCMay 14, 23:45 UTC1h 40m
2026-05-14 FDX447 PHL → MEM May 14, 12:05 UTCMay 14, 13:55 UTC1h 50m
2026-05-14 FDX1704 IND → PHL May 14, 08:55 UTCMay 14, 10:15 UTC1h 20m
2026-05-14 FDX1684 FLL → IND May 14, 02:20 UTCMay 14, 04:45 UTC2h 25m
2026-05-14 FDX1684 FLL → IND May 14, 02:18 UTCMay 14, 04:39 UTC2h 21m
2026-05-13 FDX331 MEM → FLL May 13, 21:50 UTCMay 13, 23:40 UTC1h 50m
2026-05-13 FDX331 MEM → FLL May 13, 21:45 UTCMay 13, 23:40 UTC1h 55m
2026-05-13 FDX630 SEA → MEM May 13, 13:05 UTCMay 13, 16:40 UTC3h 35m
2026-05-13 FDX1885 OAK → SEA May 13, 09:40 UTCMay 13, 11:10 UTC1h 30m
2026-05-13 FDX1807 PDX → OAK May 13, 03:55 UTCMay 13, 05:25 UTC1h 30m
2026-05-12 FDX382 PDX → OAK May 12, 21:55 UTCMay 13, 01:55 UTC4h 0m
2026-05-12 FDX382 PDX → OAK May 12, 21:50 UTCMay 13, 01:55 UTC4h 5m
2026-05-12 FDX252 SJU → MEM May 12, 13:55 UTCMay 12, 18:00 UTC4h 5m
2026-05-12 FDX51 MEM → SJU May 12, 11:50 UTCMay 12, 12:15 UTC25m
2026-05-12 FDX51 MEM → SJU May 12, 08:45 UTCMay 12, 10:30 UTC1h 45m
2026-05-12 FDX1283 IND → MEM May 12, 03:50 UTCMay 12, 04:50 UTC1h 0m
2026-05-08 FDX1574 MEM → IND May 8, 08:49 UTCMay 8, 09:44 UTC55m
2026-05-08 FDX1201 DFW → MEM May 8, 02:44 UTCMay 8, 03:44 UTC1h 0m
2026-05-07 FDX1471 MEM → DFW May 7, 07:40 UTCMay 7, 08:50 UTC1h 10m
2026-05-07 FDX1203 PHX → MEM May 7, 01:25 UTCMay 7, 03:10 UTC1h 45m
2026-05-06 FDX1446 MEM → PIT May 6, 10:20 UTCMay 6, 11:35 UTC1h 15m
2026-05-06 FDX1229 SMF → MEM May 6, 02:20 UTCMay 6, 05:45 UTC3h 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 N249FE page for operator, model, and routing details .

Mode-S A251F0 frequently asked

What is Mode-S code A251F0?
A251F0 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N249FE.
Where is Mode-S A251F0 registered?
Mode-S code A251F0 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 A251F0 broadcasting right now?
No active broadcast right now. Last signal was 19h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A251F0, octal 50450760, decimal 10,637,808.
What flights does A251F0 operate?
Mode-S A251F0 has broadcast 20 distinct callsigns, including FDX51, FDX1443, FDX64, FDX568, FDX1874.