Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A10E23

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N16703 · BOEING 737-700 · operated by UNITED AIRLINES INC

Hex
A10E23
Octal
50207043
Decimal
10,554,915
Country
US
Tail
N16703
Type
B737
No current signal · last broadcast Jul 26, 22:45 UTC
Flights observed
418
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 22:45 UTC

Last known position

Most recent position reported by Mode-S A10E23.

Country allocation

The ICAO 24-bit address A10E23 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
UAL632 - 11 2026-07-05
UAL1513 United Airlines 7 2026-07-25
UAL661 - 6 2026-07-15
UAL1764 - 6 2026-07-05
UAL1690 - 6 2026-07-13
UAL752 United Airlines 5 2026-06-07
UAL1746 United Airlines 5 2026-07-19
UAL780 United Airlines 4 2026-06-03
UAL630 United Airlines 4 2026-07-19
UAL528 United Airlines 4 2026-06-09
UAL511 United Airlines 4 2026-05-28
UAL410 - 4 2026-07-06
UAL358 United Airlines 4 2026-06-09
UAL2652 United Airlines 4 2026-05-02
UAL2612 United Airlines 4 2026-07-25
UAL2454 United Airlines 4 2026-07-16
UAL1890 - 4 2026-07-14
UAL1869 - 4 2026-07-06
UAL1732 United Airlines 4 2026-05-05
UAL1564 United Airlines 4 2026-04-15

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 UAL2407 TPA → EWR Jul 26, 21:15 UTCJul 26, 22:45 UTC1h 30m
2026-07-26 UAL2485 ORD → DEN Jul 26, 18:45 UTCJul 26, 19:55 UTC1h 10m
2026-07-25 UAL2612 EWR → PHX Jul 25, 22:50 UTCJul 26, 17:00 UTC18h 11m
2026-07-25 UAL1513 IAH → SFO Jul 25, 18:55 UTCJul 25, 21:35 UTC2h 40m
2026-07-25 UAL1418 SFO → DEN Jul 25, 14:35 UTCJul 25, 17:10 UTC2h 35m
2026-07-23 UAL3912 LAX → SFO Jul 23, 02:22 UTCJul 23, 03:56 UTC1h 34m
2026-07-23 UAL3912 LAX → SFO Jul 23, 02:25 UTCJul 23, 04:00 UTC1h 35m
2026-07-22 UAL2631 ORD → MCI Jul 22, 16:15 UTCJul 22, 18:05 UTC1h 50m
2026-07-21 UAL592 CHS → ORD Jul 21, 16:05 UTCJul 21, 18:05 UTC2h 0m
2026-07-21 UAL2795 - Jul 21, 12:50 UTCJul 21, 14:25 UTC1h 35m
2026-07-20 UAL1193 IAH → SFO Jul 20, 23:30 UTCJul 21, 01:10 UTC1h 39m
2026-07-20 UAL1941 IAD → EWR Jul 20, 20:35 UTCJul 20, 22:00 UTC1h 25m
2026-07-20 UAL1941 IAD → EWR Jul 20, 20:36 UTCJul 20, 21:54 UTC1h 18m
2026-07-20 UAL1288 OGG → SFO Jul 20, 14:25 UTCJul 20, 18:10 UTC3h 45m
2026-07-20 UAL2243 SFO → EUG Jul 20, 01:50 UTCJul 20, 05:35 UTC3h 45m
2026-07-19 UAL2860 - Jul 19, 22:20 UTCJul 19, 23:55 UTC1h 35m
2026-07-19 UAL1746 LIH → SFO Jul 19, 19:10 UTCJul 19, 20:25 UTC1h 15m
2026-07-19 UAL503 RDU → EWR Jul 19, 14:55 UTCJul 19, 17:20 UTC2h 25m
2026-07-19 UAL503 RDU → EWR Jul 19, 14:49 UTCJul 19, 17:01 UTC2h 12m
2026-07-19 UAL1186 - Jul 19, 11:15 UTCJul 19, 13:00 UTC1h 45m
2026-07-19 UAL630 BUF → ORD Jul 19, 06:05 UTCJul 19, 06:10 UTC5m
2026-07-19 UAL630 BUF → ORD Jul 19, 04:10 UTCJul 19, 06:10 UTC2h 0m
2026-07-19 UAL630 BUF → ORD Jul 19, 04:09 UTCJul 19, 05:49 UTC1h 40m
2026-07-19 UAL3915 BOS → SFO Jul 19, 01:00 UTCJul 19, 02:15 UTC1h 15m
2026-07-17 UAL1548 - Jul 17, 23:25 UTCJul 18, 17:15 UTC17h 51m
2026-07-17 UAL2050 - Jul 17, 19:15 UTCJul 17, 22:10 UTC2h 55m
2026-07-17 UAL1383 - Jul 17, 14:50 UTCJul 17, 17:44 UTC2h 55m
2026-07-17 UAL2490 - Jul 17, 00:10 UTCJul 17, 01:49 UTC1h 40m
2026-07-16 UAL2490 BNA → IAH Jul 16, 23:56 UTCJul 17, 01:46 UTC1h 50m
2026-07-16 UAL2454 ORD → LGA Jul 16, 20:29 UTCJul 16, 22:19 UTC1h 50m
2026-07-16 UAL2612 - Jul 16, 16:25 UTCJul 16, 18:50 UTC2h 25m
2026-07-16 UAL2772 EWR → SRQ Jul 16, 12:40 UTCJul 16, 15:10 UTC2h 30m
2026-07-16 UAL554 - Jul 16, 03:00 UTCJul 16, 04:05 UTC1h 5m
2026-07-15 UAL2172 - Jul 15, 21:40 UTCJul 15, 22:50 UTC1h 10m
2026-07-15 UAL661 - Jul 15, 14:05 UTCJul 15, 19:10 UTC5h 5m
2026-07-15 UAL308T ORD → SNA Jul 15, 01:25 UTCJul 15, 04:50 UTC3h 25m
2026-07-14 UAL291 SAV → ORD Jul 14, 21:40 UTCJul 14, 23:25 UTC1h 44m
2026-07-14 UAL2631 - Jul 14, 16:55 UTCJul 14, 18:35 UTC1h 40m
2026-07-14 UAL1448 - Jul 14, 14:05 UTCJul 14, 15:45 UTC1h 40m
2026-07-14 UAL1448 RDU → ORD Jul 14, 14:15 UTCJul 14, 15:27 UTC1h 12m
2026-07-14 UAL1890 - Jul 14, 11:30 UTCJul 14, 12:40 UTC1h 10m
2026-07-14 UAL2186 - Jul 14, 04:25 UTCJul 14, 09:30 UTC5h 5m
2026-07-13 UAL1690 - Jul 13, 21:30 UTCJul 14, 02:25 UTC4h 55m
2026-07-13 UAL661 - Jul 13, 14:05 UTCJul 13, 19:15 UTC5h 10m
2026-07-13 UAL308 - Jul 13, 01:05 UTCJul 13, 04:35 UTC3h 30m
2026-07-12 UAL630 - Jul 12, 21:25 UTCJul 12, 23:15 UTC1h 50m
2026-07-12 UAL2485 EWR → RDU Jul 12, 18:53 UTCJul 12, 20:05 UTC1h 12m
2026-07-11 UAL1548 EWR → EWR Jul 11, 23:15 UTCJul 12, 17:15 UTC18h 0m
2026-07-11 UAL1513 - Jul 11, 18:45 UTCJul 11, 21:20 UTC2h 35m
2026-07-11 UAL1418 - Jul 11, 14:40 UTCJul 11, 17:05 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 N16703 page for operator, model, and routing details .

Mode-S A10E23 frequently asked

What is Mode-S code A10E23?
A10E23 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N16703.
Where is Mode-S A10E23 registered?
Mode-S code A10E23 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 A10E23 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 22:45 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A10E23, octal 50207043, decimal 10,554,915.
What flights does A10E23 operate?
Mode-S A10E23 has broadcast 20 distinct callsigns, including UAL632, UAL1513, UAL661, UAL1764, UAL1690.