sensors Mode-S transponder

A5D668

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N47524 · BOEING 737 MAX 9 · operated by WILMINGTON TRUST CO TRUSTEE

Hex
A5D668
Octal
51353150
Decimal
10,868,328
Country
US
Tail
N47524
Type
B39M
Broadcasting now · callsign UAL1021 · 37,000 ft
Flights observed
6
Distinct callsigns
5
Country
US
Last broadcast
23h ago

Current position

A5D668 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A5D668 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
UAL1491 - 2 2026-04-13
UAL378 United Airlines 1 2026-04-13
UAL2614 - 1 2026-04-13
UAL2364 - 1 2026-04-12
UAL1020 - 1 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 UAL1020 - Apr 13, 22:20 UTCApr 13, 23:45 UTC1h 25m
2026-04-13 UAL378 ORD → EWR Apr 13, 17:50 UTCApr 13, 19:50 UTC2h 0m
2026-04-13 UAL2614 - Apr 13, 12:54 UTCApr 13, 15:13 UTC2h 19m
2026-04-13 UAL1491 - Apr 13, 00:20 UTCApr 13, 03:20 UTC3h 0m
2026-04-12 UAL1491 - Apr 12, 23:55 UTCApr 13, 03:20 UTC3h 25m
2026-04-12 UAL2364 - Apr 12, 18:40 UTCApr 12, 20:15 UTC1h 35m

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 N47524 page for operator, model, and routing details .

Mode-S A5D668 frequently asked

What is Mode-S code A5D668?
A5D668 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N47524.
Where is Mode-S A5D668 registered?
Mode-S code A5D668 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 A5D668 broadcasting right now?
Yes. Mode-S A5D668 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A5D668, octal 51353150, decimal 10,868,328.
What flights does A5D668 operate?
Mode-S A5D668 has broadcast 5 distinct callsigns, including UAL1491, UAL378, UAL2614, UAL2364, UAL1020.