Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A2B8C5

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N27477 · BOEING 737-900 · operated by UNITED AIRLINES INC

Hex
A2B8C5
Octal
50534305
Decimal
10,664,133
Country
US
Tail
N27477
Type
B739
No current signal · last broadcast Jul 26, 21:15 UTC
Flights observed
430
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 21:15 UTC

Last known position

Most recent position reported by Mode-S A2B8C5.

Country allocation

The ICAO 24-bit address A2B8C5 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
UAL1875 United Airlines 8 2026-05-26
UAL1863 United Airlines 6 2026-04-16
UAL630 United Airlines 5 2026-04-15
UAL1835 - 5 2026-06-19
UAL1575 United Airlines 5 2026-07-25
UAL622 United Airlines 4 2026-07-23
UAL533 United Airlines 4 2026-05-30
UAL279 - 4 2026-07-13
UAL2370 United Airlines 4 2026-06-17
UAL2330 - 4 2026-06-26
UAL2091 United Airlines 4 2026-06-09
UAL794 United Airlines 3 2026-07-23
UAL765 United Airlines 3 2026-06-13
UAL600 - 3 2026-06-24
UAL403 - 3 2026-07-13
UAL2863 United Airlines 3 2026-05-19
UAL2801 - 3 2026-07-05
UAL2659 United Airlines 3 2026-05-19
UAL2622 - 3 2026-07-05
UAL2612 United Airlines 3 2026-05-19

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 UAL1302 EWR → BOS Jul 26, 19:45 UTCJul 26, 21:15 UTC1h 30m
2026-07-26 UAL597 EWR → LAS Jul 26, 16:25 UTCJul 26, 17:45 UTC1h 20m
2026-07-26 UAL1729 DEN → EWR Jul 26, 02:05 UTCJul 26, 03:35 UTC1h 30m
2026-07-26 UAL1729 DEN → EWR Jul 26, 01:52 UTCJul 26, 03:23 UTC1h 31m
2026-07-25 UAL2644 AUS → IAH Jul 25, 20:35 UTCJul 26, 00:05 UTC3h 30m
2026-07-25 UAL2644 AUS → IAH Jul 25, 20:29 UTCJul 25, 23:57 UTC3h 28m
2026-07-25 UAL1575 MSP → EWR Jul 25, 15:55 UTCJul 25, 18:55 UTC3h 0m
2026-07-25 UAL1010 OMA → SFO Jul 25, 12:15 UTCJul 25, 14:05 UTC1h 50m
2026-07-25 UAL2095 ORD → LAX Jul 25, 01:20 UTCJul 25, 04:05 UTC2h 45m
2026-07-24 UAL1387 ORD → PIT Jul 24, 19:40 UTCJul 24, 23:25 UTC3h 45m
2026-07-24 UAL2744 MCO → EWR Jul 24, 13:40 UTCJul 24, 17:05 UTC3h 25m
2026-07-23 UAL1392 EWR → CLT Jul 23, 23:20 UTCJul 24, 02:55 UTC3h 35m
2026-07-23 UAL794 EWR → SAN Jul 23, 19:35 UTCJul 23, 21:25 UTC1h 50m
2026-07-23 UAL622 LAX → ORD Jul 23, 15:15 UTCJul 23, 16:05 UTC50m
2026-07-23 UAL2779 FRA → SFO Jul 23, 12:55 UTCJul 23, 13:45 UTC50m
2026-07-22 UAL254 ORD → BOS Jul 22, 22:55 UTCJul 23, 00:55 UTC2h 0m
2026-07-22 UAL1539 NAS → EWR Jul 22, 18:00 UTCJul 22, 20:05 UTC2h 5m
2026-07-22 UAL1456 EWR → NAS Jul 22, 12:39 UTCJul 22, 15:58 UTC3h 19m
2026-07-22 UAL1456 EWR → NAS Jul 22, 13:10 UTCJul 22, 15:45 UTC2h 35m
2026-07-21 UAL1864 - Jul 21, 11:35 UTCJul 21, 14:05 UTC2h 30m
2026-07-21 UAL1496 - Jul 21, 01:00 UTCJul 21, 03:15 UTC2h 15m
2026-07-20 UAL1496 - Jul 20, 21:50 UTCJul 20, 23:45 UTC1h 55m
2026-07-20 UAL557 - Jul 20, 13:30 UTCJul 20, 14:35 UTC1h 5m
2026-07-20 UAL1417 DEN → RDU Jul 20, 02:10 UTCJul 20, 03:15 UTC1h 5m
2026-07-19 UAL395 EWR → SFO Jul 19, 20:35 UTCJul 19, 23:40 UTC3h 5m
2026-07-19 UAL1421 - Jul 19, 16:55 UTCJul 19, 18:55 UTC2h 0m
2026-07-19 UAL1825 IAD → FLL Jul 19, 13:25 UTCJul 19, 15:30 UTC2h 5m
2026-07-19 UAL1825 IAD → FLL Jul 19, 13:13 UTCJul 19, 15:28 UTC2h 15m
2026-07-19 UAL1576 TPA → IAD Jul 19, 00:05 UTCJul 19, 02:00 UTC1h 55m
2026-07-18 UAL1576 EWR → TPA Jul 18, 16:05 UTCJul 18, 18:15 UTC2h 10m
2026-07-18 UAL2147 MIA → EWR Jul 18, 11:10 UTCJul 18, 11:55 UTC45m
2026-07-18 UAL1573 SFO → BOS Jul 18, 00:10 UTCJul 18, 04:50 UTC4h 41m
2026-07-17 UAL1689 - Jul 17, 17:35 UTCJul 17, 22:05 UTC4h 30m
2026-07-17 UAL1893 - Jul 17, 14:24 UTCJul 17, 16:04 UTC1h 40m
2026-07-16 UAL1932 - Jul 16, 00:55 UTCJul 16, 02:55 UTC2h 0m
2026-07-15 UAL1574 DFW → EWR Jul 15, 18:30 UTCJul 15, 22:55 UTC4h 25m
2026-07-15 UAL454 - Jul 15, 13:30 UTCJul 15, 16:35 UTC3h 5m
2026-07-15 UAL1652 YVR → EWR Jul 15, 06:30 UTCJul 15, 10:50 UTC4h 20m
2026-07-14 UAL1423 EWR → YVR Jul 14, 21:35 UTCJul 15, 02:45 UTC5h 9m
2026-07-14 UAL1340 - Jul 14, 17:00 UTCJul 14, 20:05 UTC3h 5m
2026-07-14 UAL2438 EWR → IAH Jul 14, 11:24 UTCJul 14, 14:42 UTC3h 18m
2026-07-14 UAL2438 - Jul 14, 11:25 UTCJul 14, 14:40 UTC3h 15m
2026-07-14 UAL759 - Jul 14, 01:25 UTCJul 14, 03:10 UTC1h 45m
2026-07-13 UAL403 FLL → ORD Jul 13, 21:00 UTCJul 13, 23:50 UTC2h 50m
2026-07-13 UAL403 FLL → ORD Jul 13, 21:04 UTCJul 13, 23:38 UTC2h 34m
2026-07-13 UAL279 - Jul 13, 16:40 UTCJul 13, 19:35 UTC2h 55m
2026-07-13 UAL1933 - Jul 13, 13:15 UTCJul 13, 14:45 UTC1h 30m
2026-07-13 UAL1625 - Jul 13, 02:55 UTCJul 13, 03:50 UTC55m
2026-07-12 UAL2106 - Jul 12, 20:35 UTCJul 12, 23:30 UTC2h 55m
2026-07-12 UAL1620 - Jul 12, 16:15 UTCJul 12, 18:55 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 N27477 page for operator, model, and routing details .

Mode-S A2B8C5 frequently asked

What is Mode-S code A2B8C5?
A2B8C5 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N27477.
Where is Mode-S A2B8C5 registered?
Mode-S code A2B8C5 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 A2B8C5 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:15 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A2B8C5, octal 50534305, decimal 10,664,133.
What flights does A2B8C5 operate?
Mode-S A2B8C5 has broadcast 20 distinct callsigns, including UAL1875, UAL1863, UAL630, UAL1835, UAL1575.