sensors Mode-S transponder

A44591

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N3744F · BOEING 737-800 · operated by DELTA AIR LINES INC

Hex
A44591
Octal
51042621
Decimal
10,765,713
Country
US
Tail
N3744F
Type
B738
Transponder active on ground
Flights observed
8
Distinct callsigns
4
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A44591.

Country allocation

The ICAO 24-bit address A44591 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 4 distinct

Callsign Airline Flights Last seen
DAL2922 Delta Air Lines 5 2026-04-13
DAL2613 - 1 2026-04-13
DAL2442 - 1 2026-04-13
DAL1714 - 1 2026-04-12

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 DAL2613 - Apr 13, 22:05 UTCApr 14, 00:20 UTC2h 15m
2026-04-13 DAL2922 MSP → MSN Apr 13, 19:50 UTCApr 13, 20:25 UTC35m
2026-04-13 DAL2922 MSP → MSN Apr 13, 18:14 UTCApr 13, 20:27 UTC2h 13m
2026-04-13 DAL2922 MSP → MSN Apr 13, 16:15 UTCApr 13, 16:40 UTC25m
2026-04-13 DAL2922 MSP → MSN Apr 13, 15:50 UTCApr 13, 16:40 UTC50m
2026-04-13 DAL2922 MSP → MSN Apr 13, 14:40 UTCApr 13, 16:15 UTC1h 35m
2026-04-13 DAL2442 PHX → SEA Apr 13, 00:55 UTCApr 13, 03:25 UTC2h 30m
2026-04-12 DAL1714 - Apr 12, 17:04 UTCApr 12, 19:21 UTC2h 17m

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 N3744F page for operator, model, and routing details .

Mode-S A44591 frequently asked

What is Mode-S code A44591?
A44591 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N3744F.
Where is Mode-S A44591 registered?
Mode-S code A44591 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 A44591 broadcasting right now?
Mode-S A44591 is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A44591, octal 51042621, decimal 10,765,713.
What flights does A44591 operate?
Mode-S A44591 has broadcast 4 distinct callsigns, including DAL2922, DAL2613, DAL2442, DAL1714.