sensors Mode-S transponder

A9F818

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N741UW · AIRBUS A-319 · operated by BANK OF UTAH TRUSTEE

Hex
A9F818
Octal
52374030
Decimal
11,139,096
Country
US
Tail
N741UW
Type
A319
Photo of N741UW
No current signal · last broadcast 23h ago
Flights observed
8
Distinct callsigns
7
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A9F818.

Country allocation

The ICAO 24-bit address A9F818 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 7 distinct

Callsign Airline Flights Last seen
AAL3044 - 2 2026-04-13
AAL925 - 1 2026-04-12
AAL2678 - 1 2026-04-13
AAL17 American Airlines 1 2026-04-13
AAL1488 American Airlines 1 2026-04-13
AAL1332 - 1 2026-04-13
AAL1319 - 1 2026-04-13

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 AAL1332 - Apr 13, 22:04 UTCApr 13, 23:29 UTC1h 25m
2026-04-13 AAL1488 CMW → MIA Apr 13, 18:49 UTCApr 13, 19:55 UTC1h 6m
2026-04-13 AAL1319 - Apr 13, 16:30 UTCApr 13, 16:55 UTC25m
2026-04-13 AAL2678 - Apr 13, 13:22 UTCApr 13, 14:05 UTC43m
2026-04-13 AAL17 MIA → HAV Apr 13, 11:15 UTCApr 13, 11:50 UTC35m
2026-04-13 AAL3044 TPA → MIA Apr 13, 02:25 UTCApr 13, 03:05 UTC40m
2026-04-13 AAL3044 - Apr 13, 00:55 UTCApr 13, 01:35 UTC40m
2026-04-12 AAL925 - Apr 12, 17:32 UTCApr 12, 19:55 UTC2h 23m

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 N741UW page for operator, model, and routing details .

Mode-S A9F818 frequently asked

What is Mode-S code A9F818?
A9F818 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N741UW.
Where is Mode-S A9F818 registered?
Mode-S code A9F818 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 A9F818 broadcasting right now?
No active broadcast right now. Last signal was 23h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9F818, octal 52374030, decimal 11,139,096.
What flights does A9F818 operate?
Mode-S A9F818 has broadcast 7 distinct callsigns, including AAL3044, AAL925, AAL2678, AAL17, AAL1488.