sensors Mode-S transponder

A77D7A

ICAO 24-bit transponder address · allocated to United States

Hex
A77D7A
Octal
51676572
Decimal
10,976,634
Country
US
Broadcasting now · callsign N582BL · 1,200 ft
Flights observed
21
Distinct callsigns
1
Country
US
Last broadcast
2h ago

Current position

A77D7A is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A77D7A 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 1 distinct

Callsign Airline Flights Last seen
N582BL - 21 2026-04-18

Recent flights last 21

DateFlightRouteTakeoffLandingDuration
2026-04-18 N582BL - Apr 18, 13:00 UTCApr 18, 14:40 UTC1h 40m
2026-04-18 N582BL - Apr 18, 02:00 UTCApr 18, 03:20 UTC1h 20m
2026-04-18 N582BL - Apr 18, 00:25 UTCApr 18, 01:00 UTC35m
2026-04-17 N582BL - Apr 17, 21:25 UTCApr 17, 22:25 UTC1h 0m
2026-04-17 N582BL - Apr 17, 20:15 UTCApr 17, 21:20 UTC1h 5m
2026-04-17 N582BL - Apr 17, 13:00 UTCApr 17, 13:15 UTC15m
2026-04-16 N582BL - Apr 16, 15:40 UTCApr 16, 17:10 UTC1h 30m
2026-04-16 N582BL - Apr 16, 12:34 UTCApr 16, 13:05 UTC30m
2026-04-15 N582BL - Apr 15, 17:10 UTCApr 15, 17:50 UTC40m
2026-04-15 N582BL - Apr 15, 13:30 UTCApr 15, 14:10 UTC40m
2026-04-15 N582BL - Apr 15, 11:45 UTCApr 15, 12:45 UTC1h 0m
2026-04-14 N582BL - Apr 14, 23:25 UTCApr 15, 00:10 UTC45m
2026-04-14 N582BL - Apr 14, 22:05 UTCApr 14, 22:30 UTC25m
2026-04-14 N582BL - Apr 14, 19:30 UTCApr 14, 20:25 UTC55m
2026-04-14 N582BL - Apr 14, 18:35 UTCApr 14, 18:45 UTC10m
2026-04-14 N582BL - Apr 14, 16:50 UTCApr 14, 17:50 UTC1h 0m
2026-04-14 N582BL - Apr 14, 16:30 UTCApr 14, 16:45 UTC15m
2026-04-14 N582BL - Apr 14, 13:50 UTCApr 14, 14:10 UTC20m
2026-04-14 N582BL - Apr 14, 12:50 UTCApr 14, 13:00 UTC10m
2026-04-14 N582BL - Apr 14, 12:15 UTCApr 14, 12:45 UTC30m
2026-04-12 N582BL - Apr 12, 17:15 UTCApr 12, 17:50 UTC35m

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.

Mode-S A77D7A frequently asked

What is Mode-S code A77D7A?
A77D7A is an ICAO 24-bit transponder address. Allocated to United States.
Where is Mode-S A77D7A registered?
Mode-S code A77D7A 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 A77D7A broadcasting right now?
Yes. Mode-S A77D7A is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A77D7A, octal 51676572, decimal 10,976,634.
What flights does A77D7A operate?
Mode-S A77D7A has broadcast 1 distinct callsign, including N582BL.