Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

AAA244

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N78438 · BOEING 737-900 · operated by UNITED AIRLINES INC, ATTN TREASURER

Hex
AAA244
Octal
52521104
Decimal
11,182,660
Country
US
Tail
N78438
Type
B739
No current signal · last broadcast Jul 26, 21:30 UTC
Flights observed
455
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 21:30 UTC

Last known position

Most recent position reported by Mode-S AAA244.

Country allocation

The ICAO 24-bit address AAA244 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
UAL777 - 5 2026-06-25
UAL495 United Airlines 5 2026-05-17
UAL1623 - 5 2026-06-27
UAL1620 - 5 2026-07-17
UAL752 - 4 2026-06-17
UAL567 - 4 2026-07-17
UAL1923 - 4 2026-07-11
UAL1797 - 4 2026-07-14
UAL1051 United Airlines 4 2026-07-19
UAL793 United Airlines 3 2026-05-30
UAL779 United Airlines 3 2026-05-17
UAL728 United Airlines 3 2026-07-24
UAL688 United Airlines 3 2026-04-15
UAL611 - 3 2026-07-12
UAL293 United Airlines 3 2026-05-25
UAL2852 - 3 2026-04-13
UAL2741 United Airlines 3 2026-05-31
UAL2639 United Airlines 3 2026-05-16
UAL2495 United Airlines 3 2026-05-17
UAL2443 - 3 2026-06-17

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 UAL1393 EWR → ORD Jul 26, 19:50 UTCJul 26, 21:30 UTC1h 40m
2026-07-26 UAL2081 SFO → IAH Jul 26, 13:15 UTCJul 26, 17:55 UTC4h 40m
2026-07-26 UAL2081 SFO → IAH Jul 26, 13:18 UTCJul 26, 17:52 UTC4h 34m
2026-07-26 UAL1971 EWR → SAT Jul 26, 02:15 UTCJul 26, 02:55 UTC40m
2026-07-26 UAL1971 EWR → SAT Jul 26, 02:21 UTCJul 26, 02:52 UTC31m
2026-07-25 UAL716 CHS → DEN Jul 25, 22:40 UTCJul 26, 00:20 UTC1h 40m
2026-07-25 UAL2793 IAD → EWR Jul 25, 18:25 UTCJul 25, 20:30 UTC2h 5m
2026-07-25 UAL1247 EWR → FLL Jul 25, 14:20 UTCJul 25, 16:30 UTC2h 10m
2026-07-25 UAL1464 EWR → FLL Jul 25, 10:50 UTCJul 25, 12:40 UTC1h 50m
2026-07-25 UAL395 EWR → SFO Jul 25, 05:34 UTCJul 25, 06:57 UTC1h 23m
2026-07-25 UAL395 EWR → SFO Jul 25, 05:20 UTCJul 25, 07:00 UTC1h 40m
2026-07-25 UAL1291 EWR → BNA Jul 25, 02:35 UTCJul 25, 04:00 UTC1h 25m
2026-07-24 UAL716 CHS → DEN Jul 24, 23:15 UTCJul 25, 00:45 UTC1h 30m
2026-07-24 UAL1248 SFO → ORD Jul 24, 17:50 UTCJul 24, 21:55 UTC4h 5m
2026-07-24 UAL728 AUS → EWR Jul 24, 13:10 UTCJul 24, 15:45 UTC2h 35m
2026-07-24 UAL728 AUS → EWR Jul 24, 13:13 UTCJul 24, 15:43 UTC2h 30m
2026-07-24 UAL1843 SFO → ORD Jul 24, 00:15 UTCJul 24, 02:25 UTC2h 10m
2026-07-23 UAL1961 LAS → IAD Jul 23, 20:15 UTCJul 23, 22:30 UTC2h 15m
2026-07-23 UAL2145 MFR → SFO Jul 23, 14:45 UTCJul 23, 18:35 UTC3h 50m
2026-07-23 UAL2333 ORD → SFO Jul 23, 10:30 UTCJul 23, 12:30 UTC2h 0m
2026-07-23 UAL2362 LGA → ORD Jul 23, 00:15 UTCJul 23, 01:45 UTC1h 30m
2026-07-22 UAL1748 PHX → ORD Jul 22, 18:25 UTCJul 22, 21:25 UTC3h 0m
2026-07-22 UAL659 EWR → IAD Jul 22, 15:45 UTCJul 22, 16:40 UTC55m
2026-07-22 UAL2110 SAN → SFO Jul 22, 11:40 UTCJul 22, 14:10 UTC2h 30m
2026-07-21 UAL588 ATL → EWR Jul 21, 22:40 UTCJul 22, 00:35 UTC1h 55m
2026-07-21 UAL2793 IAD → EWR Jul 21, 18:25 UTCJul 21, 20:30 UTC2h 5m
2026-07-21 UAL1247 DEN → PDX Jul 21, 14:20 UTCJul 21, 16:30 UTC2h 10m
2026-07-20 UAL235 ATL → DEN Jul 20, 21:00 UTCJul 20, 23:35 UTC2h 35m
2026-07-20 UAL2424 LAX → BOS Jul 20, 17:10 UTCJul 20, 19:40 UTC2h 30m
2026-07-20 UAL2424 LAX → BOS Jul 20, 16:31 UTCJul 20, 19:37 UTC3h 6m
2026-07-20 UAL1745 SFO → IAH Jul 20, 03:10 UTCJul 20, 04:35 UTC1h 25m
2026-07-19 UAL2053 SFO → PDX Jul 19, 23:05 UTCJul 20, 02:00 UTC2h 55m
2026-07-19 UAL2053 SFO → PDX Jul 19, 19:20 UTCJul 19, 21:25 UTC2h 5m
2026-07-19 UAL1051 CUN → EWR Jul 19, 15:10 UTCJul 19, 16:00 UTC50m
2026-07-18 UAL1051 CUN → EWR Jul 18, 18:55 UTCJul 18, 22:40 UTC3h 45m
2026-07-18 UAL1018 - Jul 18, 15:20 UTCJul 18, 17:35 UTC2h 15m
2026-07-18 UAL2310 - Jul 18, 10:45 UTCJul 18, 12:40 UTC1h 55m
2026-07-18 UAL2310 ORD → IAH Jul 18, 10:50 UTCJul 18, 12:38 UTC1h 48m
2026-07-18 UAL2106 - Jul 18, 01:34 UTCJul 18, 04:05 UTC2h 31m
2026-07-17 UAL1620 - Jul 17, 22:35 UTCJul 17, 23:00 UTC25m
2026-07-17 UAL1620 - Jul 17, 20:25 UTCJul 17, 20:35 UTC10m
2026-07-17 UAL1620 ORD → PBI Jul 17, 16:55 UTCJul 17, 20:35 UTC3h 40m
2026-07-17 UAL1620 ORD → MIA Jul 17, 16:31 UTCJul 17, 20:08 UTC3h 37m
2026-07-17 UAL567 - Jul 17, 12:50 UTCJul 17, 13:45 UTC55m
2026-07-17 UAL567 MSP → ORD Jul 17, 12:52 UTCJul 17, 13:43 UTC51m
2026-07-17 UAL2005 ORD → MSP Jul 17, 02:45 UTCJul 17, 03:50 UTC1h 5m
2026-07-16 UAL2106 - Jul 16, 21:50 UTCJul 17, 01:00 UTC3h 10m
2026-07-16 UAL1620 - Jul 16, 17:10 UTCJul 16, 19:55 UTC2h 45m
2026-07-16 UAL567 MSP → ORD Jul 16, 12:52 UTCJul 16, 13:41 UTC49m
2026-07-16 UAL567 MSP → ORD Jul 16, 12:49 UTCJul 16, 14:15 UTC1h 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 N78438 page for operator, model, and routing details .

Mode-S AAA244 frequently asked

What is Mode-S code AAA244?
AAA244 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N78438.
Where is Mode-S AAA244 registered?
Mode-S code AAA244 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 AAA244 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:30 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AAA244, octal 52521104, decimal 11,182,660.
What flights does AAA244 operate?
Mode-S AAA244 has broadcast 20 distinct callsigns, including UAL777, UAL495, UAL1623, UAL1620, UAL752.