sensors Mode-S transponder

A44548

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N3742C · BOEING 737-800 · operated by DELTA AIR LINES INC

Hex
A44548
Octal
51042510
Decimal
10,765,640
Country
US
Tail
N3742C
Type
B738
Broadcasting now · callsign DAL985 · 3,525 ft
Flights observed
6
Distinct callsigns
4
Country
US
Last broadcast
12h ago

Current position

A44548 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A44548 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
DAL909 Delta Air Lines 3 2026-04-13
DAL379 Delta Air Lines 1 2026-04-12
DAL2127 - 1 2026-04-14
DAL1434 - 1 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-14 DAL2127 - Apr 14, 10:00 UTCApr 14, 11:05 UTC1h 5m
2026-04-13 DAL1434 - Apr 13, 17:10 UTCApr 13, 18:30 UTC1h 20m
2026-04-13 DAL909 MSP → BOS Apr 13, 04:20 UTCApr 13, 05:25 UTC1h 5m
2026-04-13 DAL909 MSP → BOS Apr 13, 03:55 UTCApr 13, 05:25 UTC1h 30m
2026-04-13 DAL909 MSP → BOS Apr 13, 01:29 UTCApr 13, 05:19 UTC3h 50m
2026-04-12 DAL379 ATL → LGA Apr 12, 17:15 UTCApr 12, 19:35 UTC2h 20m

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 N3742C page for operator, model, and routing details .

Mode-S A44548 frequently asked

What is Mode-S code A44548?
A44548 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N3742C.
Where is Mode-S A44548 registered?
Mode-S code A44548 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 A44548 broadcasting right now?
Yes. Mode-S A44548 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A44548, octal 51042510, decimal 10,765,640.
What flights does A44548 operate?
Mode-S A44548 has broadcast 4 distinct callsigns, including DAL909, DAL379, DAL2127, DAL1434.