sensors Mode-S transponder

A671F2

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N514SY · EMBRAER ERJ-170-200 (long wing) · operated by SKYWEST AIRLINES INC

Hex
A671F2
Octal
51470762
Decimal
10,908,146
Country
US
Tail
N514SY
Type
E75L
No current signal · last broadcast 16h ago
Flights observed
8
Distinct callsigns
6
Country
US
Last broadcast
16h ago

Last known position

Most recent position reported by Mode-S A671F2.

Country allocation

The ICAO 24-bit address A671F2 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 6 distinct

Callsign Airline Flights Last seen
SKW6371 - 2 2026-04-12
SKW6308 SkyWest Airlines 2 2026-04-13
SKW6318 - 1 2026-04-13
SKW6241 SkyWest Airlines 1 2026-04-13
SKW5005 - 1 2026-04-13
SKW4941 - 1 2026-04-14

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-14 SKW4941 - Apr 14, 05:20 UTCApr 14, 06:50 UTC1h 30m
2026-04-13 SKW6308 IND → ORD Apr 13, 19:55 UTCApr 13, 20:10 UTC15m
2026-04-13 SKW6308 IND → ORD Apr 13, 16:40 UTCApr 13, 18:40 UTC2h 0m
2026-04-13 SKW5005 - Apr 13, 13:24 UTCApr 13, 14:38 UTC1h 14m
2026-04-13 SKW6318 - Apr 13, 03:29 UTCApr 13, 04:08 UTC39m
2026-04-13 SKW6241 SFO → PHX Apr 13, 00:25 UTCApr 13, 01:20 UTC55m
2026-04-12 SKW6371 - Apr 12, 19:46 UTCApr 12, 20:54 UTC1h 8m
2026-04-12 SKW6371 - Apr 12, 17:40 UTCApr 12, 18:55 UTC1h 15m

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 N514SY page for operator, model, and routing details .

Mode-S A671F2 frequently asked

What is Mode-S code A671F2?
A671F2 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N514SY.
Where is Mode-S A671F2 registered?
Mode-S code A671F2 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 A671F2 broadcasting right now?
No active broadcast right now. Last signal was 16h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A671F2, octal 51470762, decimal 10,908,146.
What flights does A671F2 operate?
Mode-S A671F2 has broadcast 6 distinct callsigns, including SKW6371, SKW6308, SKW6318, SKW6241, SKW5005.