sensors Mode-S transponder

A9A404

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N720EV · BOMBARDIER Regional Jet CRJ-700 · operated by SKYWEST AIRLINES INC

Hex
A9A404
Octal
52322004
Decimal
11,117,572
Country
US
Tail
N720EV
Type
CRJ7
Photo of N720EV
No current signal · last broadcast 1d ago
Flights observed
8
Distinct callsigns
5
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A9A404.

Country allocation

The ICAO 24-bit address A9A404 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
SKW6205 - 3 2026-04-13
SKW6414 SkyWest Airlines 2 2026-04-12
SKW6388 - 1 2026-04-13
SKW5003 - 1 2026-04-13
SKW4905 - 1 2026-04-13

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 SKW6388 PHX → PHX Apr 13, 23:01 UTCApr 14, 00:20 UTC1h 19m
2026-04-13 SKW6205 - Apr 13, 16:15 UTCApr 13, 16:45 UTC30m
2026-04-13 SKW6205 - Apr 13, 15:50 UTCApr 13, 16:45 UTC55m
2026-04-13 SKW6205 - Apr 13, 15:46 UTCApr 13, 16:45 UTC59m
2026-04-13 SKW4905 - Apr 13, 04:37 UTCApr 13, 06:12 UTC1h 35m
2026-04-13 SKW5003 DEN → LAX Apr 13, 00:55 UTCApr 13, 03:15 UTC2h 20m
2026-04-12 SKW6414 SLC → ORD Apr 12, 19:19 UTCApr 12, 20:35 UTC1h 16m
2026-04-12 SKW6414 SLC → ORD Apr 12, 17:15 UTCApr 12, 18:05 UTC50m

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 N720EV page for operator, model, and routing details .

Mode-S A9A404 frequently asked

What is Mode-S code A9A404?
A9A404 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N720EV.
Where is Mode-S A9A404 registered?
Mode-S code A9A404 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 A9A404 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9A404, octal 52322004, decimal 11,117,572.
What flights does A9A404 operate?
Mode-S A9A404 has broadcast 5 distinct callsigns, including SKW6205, SKW6414, SKW6388, SKW5003, SKW4905.