sensors Mode-S transponder

A437DA

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N371DN · AIRBUS A-321 · operated by DELTA AIR LINES INC

Hex
A437DA
Octal
51033732
Decimal
10,762,202
Country
US
Tail
N371DN
Type
A321
No current signal · last broadcast 18h ago
Flights observed
10
Distinct callsigns
5
Country
US
Last broadcast
18h ago

Last known position

Most recent position reported by Mode-S A437DA.

Country allocation

The ICAO 24-bit address A437DA 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 5 distinct

Callsign Airline Flights Last seen
DAL2187 Delta Air Lines 3 2026-04-13
DAL2719 Delta Air Lines 2 2026-04-13
DAL2409 - 2 2026-04-13
DAL2287 - 2 2026-04-13
DAL2998 Delta Air Lines 1 2026-04-14

Recent flights last 10

DateFlightRouteTakeoffLandingDuration
2026-04-14 DAL2998 TPA → BOS Apr 14, 05:15 UTCApr 14, 06:45 UTC1h 30m
2026-04-13 DAL2287 - Apr 13, 23:15 UTCApr 13, 23:25 UTC10m
2026-04-13 DAL2287 - Apr 13, 20:14 UTCApr 13, 22:57 UTC2h 43m
2026-04-13 DAL2409 - Apr 13, 16:15 UTCApr 13, 18:35 UTC2h 20m
2026-04-13 DAL2409 - Apr 13, 15:55 UTCApr 13, 16:15 UTC20m
2026-04-13 DAL2719 TLH → ATL Apr 13, 12:20 UTCApr 13, 14:20 UTC2h 0m
2026-04-13 DAL2719 TLH → ATL Apr 13, 12:08 UTCApr 13, 14:21 UTC2h 13m
2026-04-13 DAL2187 JFK → MCO Apr 13, 00:20 UTCApr 13, 02:45 UTC2h 25m
2026-04-12 DAL2187 JFK → MCO Apr 12, 23:55 UTCApr 13, 02:45 UTC2h 50m
2026-04-12 DAL2187 JFK → MCO Apr 12, 18:30 UTCApr 12, 20:15 UTC1h 45m

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 N371DN page for operator, model, and routing details .

Mode-S A437DA frequently asked

What is Mode-S code A437DA?
A437DA is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N371DN.
Where is Mode-S A437DA registered?
Mode-S code A437DA 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 A437DA broadcasting right now?
No active broadcast right now. Last signal was 18h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A437DA, octal 51033732, decimal 10,762,202.
What flights does A437DA operate?
Mode-S A437DA has broadcast 5 distinct callsigns, including DAL2187, DAL2719, DAL2409, DAL2287, DAL2998.