sensors Mode-S transponder

A4BF95

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N405DX · AIRBUS A-330-900 · operated by BANK OF UTAH TRUSTEE

Hex
A4BF95
Octal
51137625
Decimal
10,796,949
Country
US
Tail
N405DX
Type
A339
No current signal · last broadcast 12h ago
Flights observed
11
Distinct callsigns
5
Country
US
Last broadcast
12h ago

Last known position

Most recent position reported by Mode-S A4BF95.

Country allocation

The ICAO 24-bit address A4BF95 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
DAL59 - 3 2026-04-13
DAL16 Delta Air Lines 3 2026-04-13
DAL240 Delta Air Lines 2 2026-04-13
DAL223 - 2 2026-04-14
DAL17 Delta Air Lines 1 2026-04-12

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-14 DAL223 - Apr 14, 09:10 UTCApr 14, 11:05 UTC1h 55m
2026-04-14 DAL223 - Apr 14, 07:05 UTCApr 14, 07:10 UTC5m
2026-04-13 DAL240 BOS → ATH Apr 13, 19:50 UTCApr 13, 20:55 UTC1h 5m
2026-04-13 DAL240 BOS → ATH Apr 13, 19:30 UTCApr 13, 20:05 UTC35m
2026-04-13 DAL59 BVY → BOS Apr 13, 15:50 UTCApr 13, 16:00 UTC10m
2026-04-13 DAL59 - Apr 13, 14:35 UTCApr 13, 16:00 UTC1h 25m
2026-04-13 DAL59 - Apr 13, 09:07 UTCApr 13, 15:57 UTC6h 50m
2026-04-13 DAL16 DTW → LHR Apr 13, 04:20 UTCApr 13, 05:35 UTC1h 15m
2026-04-13 DAL16 DTW → LHR Apr 13, 00:20 UTCApr 13, 04:15 UTC3h 55m
2026-04-12 DAL16 DTW → LHR Apr 12, 23:55 UTCApr 13, 01:00 UTC1h 5m
2026-04-12 DAL17 LHR → DTW Apr 12, 17:15 UTCApr 12, 18:10 UTC55m

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 N405DX page for operator, model, and routing details .

Mode-S A4BF95 frequently asked

What is Mode-S code A4BF95?
A4BF95 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N405DX.
Where is Mode-S A4BF95 registered?
Mode-S code A4BF95 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 A4BF95 broadcasting right now?
No active broadcast right now. Last signal was 12h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4BF95, octal 51137625, decimal 10,796,949.
What flights does A4BF95 operate?
Mode-S A4BF95 has broadcast 5 distinct callsigns, including DAL59, DAL16, DAL240, DAL223, DAL17.