sensors Mode-S transponder

AD9DB0

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N977AK · BOEING 737 MAX 9 · operated by ALASKA AIRLINES INC

Hex
AD9DB0
Octal
53316660
Decimal
11,378,096
Country
US
Tail
N977AK
Type
B39M
Broadcasting now · callsign ASA405 · 21,650 ft
Flights observed
11
Distinct callsigns
5
Country
US
Last broadcast
1d ago

Current position

AD9DB0 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address AD9DB0 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
ASA21 - 5 2026-04-13
ASA16 - 2 2026-04-13
ASA1489 - 2 2026-04-12
ASA466 - 1 2026-04-13
ASA465 - 1 2026-04-13

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-13 ASA465 PDX → SEA Apr 13, 20:50 UTCApr 13, 21:20 UTC30m
2026-04-13 ASA466 SEA → PDX Apr 13, 18:50 UTCApr 13, 19:15 UTC25m
2026-04-13 ASA21 - Apr 13, 16:15 UTCApr 13, 16:50 UTC35m
2026-04-13 ASA21 - Apr 13, 15:50 UTCApr 13, 16:50 UTC1h 0m
2026-04-13 ASA21 - Apr 13, 12:20 UTCApr 13, 16:15 UTC3h 55m
2026-04-13 ASA21 - Apr 13, 11:55 UTCApr 13, 15:50 UTC3h 55m
2026-04-13 ASA21 - Apr 13, 11:15 UTCApr 13, 12:15 UTC1h 0m
2026-04-13 ASA16 - Apr 13, 00:20 UTCApr 13, 02:55 UTC2h 35m
2026-04-13 ASA16 - Apr 13, 00:10 UTCApr 13, 02:55 UTC2h 45m
2026-04-12 ASA1489 - Apr 12, 19:15 UTCApr 12, 20:15 UTC1h 0m
2026-04-12 ASA1489 - Apr 12, 17:26 UTCApr 12, 18:56 UTC1h 30m

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 N977AK page for operator, model, and routing details .

Mode-S AD9DB0 frequently asked

What is Mode-S code AD9DB0?
AD9DB0 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N977AK.
Where is Mode-S AD9DB0 registered?
Mode-S code AD9DB0 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 AD9DB0 broadcasting right now?
Yes. Mode-S AD9DB0 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AD9DB0, octal 53316660, decimal 11,378,096.
What flights does AD9DB0 operate?
Mode-S AD9DB0 has broadcast 5 distinct callsigns, including ASA21, ASA16, ASA1489, ASA466, ASA465.