sensors Mode-S transponder

ACA309

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N913NN · BOEING 737-800 · operated by BANK OF UTAH TRUSTEE

Hex
ACA309
Octal
53121411
Decimal
11,313,929
Country
US
Tail
N913NN
Type
B738
Photo of N913NN
Broadcasting now · callsign AAL1811 · 36,000 ft
Flights observed
19
Distinct callsigns
7
Country
US
Last broadcast
23h ago

Current position

ACA309 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address ACA309 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
AAL2435 - 5 2026-04-13
AAL514 - 3 2026-04-13
AAL512 - 3 2026-04-13
AAL2471 - 3 2026-04-13
AAL2327 - 3 2026-04-13
AAL2512 American Airlines 1 2026-04-13
AAL2180 American Airlines 1 2026-04-12

Recent flights last 19

DateFlightRouteTakeoffLandingDuration
2026-04-13 AAL2512 MIA → ORD Apr 13, 22:05 UTCApr 13, 23:45 UTC1h 40m
2026-04-13 AAL512 - Apr 13, 19:50 UTCApr 13, 20:55 UTC1h 5m
2026-04-13 AAL512 - Apr 13, 18:22 UTCApr 13, 20:34 UTC2h 12m
2026-04-13 AAL512 - Apr 13, 18:32 UTCApr 13, 21:03 UTC2h 31m
2026-04-13 AAL514 - Apr 13, 16:15 UTCApr 13, 17:00 UTC45m
2026-04-13 AAL514 - Apr 13, 15:50 UTCApr 13, 17:00 UTC1h 10m
2026-04-13 AAL514 - Apr 13, 15:03 UTCApr 13, 17:00 UTC1h 57m
2026-04-13 AAL2435 - Apr 13, 12:20 UTCApr 13, 13:30 UTC1h 10m
2026-04-13 AAL2435 - Apr 13, 11:55 UTCApr 13, 13:30 UTC1h 35m
2026-04-13 AAL2435 - Apr 13, 11:17 UTCApr 13, 13:48 UTC2h 31m
2026-04-13 AAL2435 - Apr 13, 11:17 UTCApr 13, 13:48 UTC2h 31m
2026-04-13 AAL2435 - Apr 13, 11:05 UTCApr 13, 13:25 UTC2h 20m
2026-04-13 AAL2327 - Apr 13, 04:20 UTCApr 13, 05:30 UTC1h 10m
2026-04-13 AAL2327 - Apr 13, 03:55 UTCApr 13, 05:30 UTC1h 35m
2026-04-13 AAL2327 - Apr 13, 03:34 UTCApr 13, 05:27 UTC1h 53m
2026-04-13 AAL2471 - Apr 13, 00:20 UTCApr 13, 02:10 UTC1h 50m
2026-04-12 AAL2471 - Apr 12, 23:55 UTCApr 13, 02:10 UTC2h 15m
2026-04-12 AAL2471 - Apr 12, 19:40 UTCApr 12, 20:15 UTC35m
2026-04-12 AAL2180 RDU → LGA Apr 12, 17:15 UTCApr 12, 18:20 UTC1h 5m

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 N913NN page for operator, model, and routing details .

Mode-S ACA309 frequently asked

What is Mode-S code ACA309?
ACA309 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N913NN.
Where is Mode-S ACA309 registered?
Mode-S code ACA309 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 ACA309 broadcasting right now?
Yes. Mode-S ACA309 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex ACA309, octal 53121411, decimal 11,313,929.
What flights does ACA309 operate?
Mode-S ACA309 has broadcast 7 distinct callsigns, including AAL2435, AAL514, AAL512, AAL2471, AAL2327.