sensors Mode-S transponder

A2C39F

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N27752 · BOEING 737 MAX 10 · operated by BOEING CO

Hex
A2C39F
Octal
50541637
Decimal
10,666,911
Country
US
Tail
N27752
Type
B3XM
Broadcasting now · callsign BOE102 · 17,900 ft
Flights observed
12
Distinct callsigns
1
Country
US
Last broadcast
1h ago

Current position

A2C39F is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A2C39F 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
BOE102 - 12 2026-05-20

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-05-20 BOE102 - May 20, 19:55 UTCMay 20, 20:55 UTC1h 0m
2026-05-20 BOE102 - May 20, 18:55 UTCMay 20, 19:05 UTC10m
2026-05-20 BOE102 - May 20, 17:05 UTCMay 20, 17:35 UTC30m
2026-05-19 BOE102 - May 19, 19:15 UTCMay 19, 20:15 UTC1h 0m
2026-05-19 BOE102 - May 19, 17:20 UTCMay 19, 17:35 UTC15m
2026-05-15 BOE102 - May 15, 21:45 UTCMay 15, 22:45 UTC1h 0m
2026-05-15 BOE102 - May 15, 19:30 UTCMay 15, 20:20 UTC50m
2026-05-15 BOE102 - May 15, 17:50 UTCMay 15, 18:05 UTC15m
2026-04-14 BOE102 - Apr 14, 22:55 UTCApr 14, 23:15 UTC20m
2026-04-14 BOE102 - Apr 14, 22:10 UTCApr 14, 22:50 UTC40m
2026-04-14 BOE102 - Apr 14, 16:50 UTCApr 14, 17:25 UTC35m
2026-04-14 BOE102 - Apr 14, 16:35 UTCApr 14, 16:45 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 N27752 page for operator, model, and routing details .

Mode-S A2C39F frequently asked

What is Mode-S code A2C39F?
A2C39F is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N27752.
Where is Mode-S A2C39F registered?
Mode-S code A2C39F 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 A2C39F broadcasting right now?
Yes. Mode-S A2C39F is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A2C39F, octal 50541637, decimal 10,666,911.
What flights does A2C39F operate?
Mode-S A2C39F has broadcast 1 distinct callsign, including BOE102.