sensors Mode-S transponder

AD639E

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N962AK · BOEING 737 MAX 9 · operated by ALASKA AIRLINES INC

Hex
AD639E
Octal
53261636
Decimal
11,363,230
Country
US
Tail
N962AK
Type
B39M
Broadcasting now · callsign ASA517 · 34,000 ft
Flights observed
9
Distinct callsigns
5
Country
US
Last broadcast
23h ago

Current position

AD639E is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address AD639E 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
ASA627 - 3 2026-04-13
ASA431 Alaska Airlines 2 2026-04-13
ASA1467 Alaska Airlines 2 2026-04-13
ASA716 Alaska Airlines 1 2026-04-13
ASA428 - 1 2026-04-12

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-13 ASA716 SFO → SAN Apr 13, 21:45 UTCApr 13, 23:45 UTC2h 0m
2026-04-13 ASA1467 LAS → PDX Apr 13, 19:50 UTCApr 13, 20:25 UTC35m
2026-04-13 ASA1467 LAS → PDX Apr 13, 18:30 UTCApr 13, 20:24 UTC1h 54m
2026-04-13 ASA627 - Apr 13, 16:15 UTCApr 13, 16:35 UTC20m
2026-04-13 ASA627 - Apr 13, 15:50 UTCApr 13, 16:35 UTC45m
2026-04-13 ASA627 - Apr 13, 14:45 UTCApr 13, 16:15 UTC1h 30m
2026-04-13 ASA431 LAX → SEA Apr 13, 00:20 UTCApr 13, 02:35 UTC2h 15m
2026-04-12 ASA431 LAX → SEA Apr 12, 23:55 UTCApr 13, 02:35 UTC2h 40m
2026-04-12 ASA428 - Apr 12, 17:40 UTCApr 12, 20:15 UTC2h 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 N962AK page for operator, model, and routing details .

Mode-S AD639E frequently asked

What is Mode-S code AD639E?
AD639E is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N962AK.
Where is Mode-S AD639E registered?
Mode-S code AD639E 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 AD639E broadcasting right now?
Yes. Mode-S AD639E is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AD639E, octal 53261636, decimal 11,363,230.
What flights does AD639E operate?
Mode-S AD639E has broadcast 5 distinct callsigns, including ASA627, ASA431, ASA1467, ASA716, ASA428.