sensors Mode-S transponder

A7B637

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N5961L · AMERICAN AA-1 · operated by ROBINSON MORTON, FAIRE KENNETH D

Hex
A7B637
Octal
51733067
Decimal
10,991,159
Country
US
Tail
N5961L
Type
AA1
No current signal · last broadcast 4h ago
Flights observed
22
Distinct callsigns
3
Country
US
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S A7B637.

Country allocation

The ICAO 24-bit address A7B637 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 3 distinct

Callsign Airline Flights Last seen
5961L - 10 2026-07-01
W - 6 2026-05-31
N5961L - 6 2026-05-05

Recent flights last 22

DateFlightRouteTakeoffLandingDuration
2026-07-01 5961L - Jul 1, 16:10 UTCJul 1, 16:25 UTC15m
2026-06-28 5961L TWD → TWD Jun 28, 15:34 UTCJun 28, 15:55 UTC20m
2026-06-25 5961L - Jun 25, 18:15 UTCJun 25, 18:45 UTC30m
2026-06-20 5961L - Jun 20, 19:40 UTCJun 20, 20:09 UTC30m
2026-06-18 5961L TWD → TWD Jun 18, 14:55 UTCJun 18, 15:25 UTC30m
2026-06-12 5961L - Jun 12, 13:50 UTCJun 12, 14:20 UTC30m
2026-06-09 5961L - Jun 9, 18:20 UTCJun 9, 18:45 UTC25m
2026-06-07 5961L - Jun 7, 18:00 UTCJun 7, 18:20 UTC20m
2026-06-05 5961L - Jun 5, 15:45 UTCJun 5, 16:25 UTC40m
2026-06-03 5961L - Jun 3, 15:35 UTCJun 3, 16:00 UTC25m
2026-05-31 W - May 31, 16:50 UTCMay 31, 17:10 UTC20m
2026-05-27 W - May 27, 14:35 UTCMay 27, 15:00 UTC25m
2026-05-24 W - May 24, 16:00 UTCMay 24, 16:15 UTC15m
2026-05-20 W - May 20, 15:45 UTCMay 20, 16:05 UTC20m
2026-05-12 W - May 12, 17:25 UTCMay 12, 17:50 UTC25m
2026-05-08 W TWD → TWD May 8, 21:50 UTCMay 8, 22:15 UTC25m
2026-05-05 N5961L - May 5, 18:40 UTCMay 5, 19:15 UTC35m
2026-04-30 N5961L - Apr 30, 22:05 UTCApr 30, 22:15 UTC10m
2026-04-30 N5961L TWD → PAE Apr 30, 21:00 UTCApr 30, 21:15 UTC15m
2026-04-27 N5961L - Apr 27, 19:05 UTCApr 27, 19:30 UTC25m
2026-04-21 N5961L - Apr 21, 21:20 UTCApr 21, 21:45 UTC25m
2026-04-18 N5961L - Apr 18, 01:10 UTCApr 18, 01:20 UTC10m

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 N5961L page for operator, model, and routing details .

Mode-S A7B637 frequently asked

What is Mode-S code A7B637?
A7B637 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N5961L.
Where is Mode-S A7B637 registered?
Mode-S code A7B637 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 A7B637 broadcasting right now?
No active broadcast right now. Last signal was 4h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A7B637, octal 51733067, decimal 10,991,159.
What flights does A7B637 operate?
Mode-S A7B637 has broadcast 3 distinct callsigns, including 5961L, W, N5961L.