sensors Mode-S transponder

A03F1E

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N115DN · AIRBUS A-321 · operated by DELTA AIR LINES INC

Hex
A03F1E
Octal
50037436
Decimal
10,501,918
Country
US
Tail
N115DN
Type
A321
Photo of N115DN
No current signal · last broadcast 1d ago
Flights observed
9
Distinct callsigns
4
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A03F1E.

Country allocation

The ICAO 24-bit address A03F1E 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
DAL729 - 4 2026-04-13
DAL753 - 2 2026-04-13
DAL1252 - 2 2026-04-13
DAL423 Delta Air Lines 1 2026-04-12

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-13 DAL753 - Apr 13, 19:50 UTCApr 13, 23:40 UTC3h 50m
2026-04-13 DAL753 - Apr 13, 18:58 UTCApr 13, 23:11 UTC4h 13m
2026-04-13 DAL729 - Apr 13, 16:15 UTCApr 13, 17:30 UTC1h 15m
2026-04-13 DAL729 - Apr 13, 15:50 UTCApr 13, 17:30 UTC1h 40m
2026-04-13 DAL729 - Apr 13, 13:40 UTCApr 13, 17:21 UTC3h 41m
2026-04-13 DAL729 - Apr 13, 13:54 UTCApr 13, 17:28 UTC3h 34m
2026-04-13 DAL1252 - Apr 13, 00:20 UTCApr 13, 01:40 UTC1h 20m
2026-04-13 DAL1252 SLC → SAN Apr 13, 00:00 UTCApr 13, 01:40 UTC1h 40m
2026-04-12 DAL423 ATL → SLC Apr 12, 18:07 UTCApr 12, 22:02 UTC3h 55m

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 N115DN page for operator, model, and routing details .

Mode-S A03F1E frequently asked

What is Mode-S code A03F1E?
A03F1E is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N115DN.
Where is Mode-S A03F1E registered?
Mode-S code A03F1E 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 A03F1E broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A03F1E, octal 50037436, decimal 10,501,918.
What flights does A03F1E operate?
Mode-S A03F1E has broadcast 4 distinct callsigns, including DAL729, DAL753, DAL1252, DAL423.