sensors Mode-S transponder

A99F2D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N719TH · CESSNA 172 Skyhawk · operated by AUBURN UNIVERSITY

Hex
A99F2D
Octal
52317455
Decimal
11,116,333
Country
US
Tail
N719TH
Type
C172
No current signal · last broadcast 11d ago
Flights observed
86
Distinct callsigns
1
Country
US
Last broadcast
11d ago

Last known position

Most recent position reported by Mode-S A99F2D.

Country allocation

The ICAO 24-bit address A99F2D 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
AUB129 - 86 2026-07-06

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-06 AUB129 AUO → AUO Jul 6, 19:50 UTCJul 6, 21:05 UTC1h 15m
2026-07-02 AUB129 AUO → AUO Jul 2, 16:45 UTCJul 2, 16:50 UTC5m
2026-07-02 AUB129 - Jul 2, 15:35 UTCJul 2, 16:10 UTC35m
2026-07-01 AUB129 AUO → AUO Jul 1, 15:20 UTCJul 1, 16:10 UTC50m
2026-06-26 AUB129 - Jun 26, 20:10 UTCJun 26, 20:20 UTC10m
2026-06-26 AUB129 - Jun 26, 19:09 UTCJun 26, 19:30 UTC20m
2026-06-25 AUB129 AUO → AUO Jun 25, 23:05 UTCJun 26, 01:50 UTC2h 45m
2026-06-25 AUB129 AUO → AUO Jun 25, 16:39 UTCJun 25, 18:00 UTC1h 20m
2026-06-24 AUB129 AUO → AUO Jun 24, 22:04 UTCJun 24, 23:00 UTC55m
2026-06-24 AUB129 AUO → AUO Jun 24, 17:45 UTCJun 24, 19:24 UTC1h 40m
2026-06-24 AUB129 AUO → AUO Jun 24, 14:15 UTCJun 24, 15:14 UTC1h 0m
2026-06-23 AUB129 AUO → AUO Jun 23, 21:45 UTCJun 23, 23:00 UTC1h 15m
2026-06-23 AUB129 AUO → AUO Jun 23, 18:25 UTCJun 23, 20:04 UTC1h 40m
2026-06-23 AUB129 AUO → AUO Jun 23, 11:45 UTCJun 23, 12:20 UTC35m
2026-06-22 AUB129 AUO → AUO Jun 22, 20:04 UTCJun 22, 20:44 UTC40m
2026-06-20 AUB129 AUO → AUO Jun 20, 17:19 UTCJun 20, 17:44 UTC25m
2026-06-18 AUB129 AUO → AUO Jun 18, 01:50 UTCJun 18, 02:20 UTC30m
2026-06-15 AUB129 AUO → AUO Jun 15, 20:50 UTCJun 15, 22:20 UTC1h 30m
2026-06-13 AUB129 - Jun 13, 02:25 UTCJun 13, 04:55 UTC2h 29m
2026-06-13 AUB129 AUO → ANB Jun 13, 01:20 UTCJun 13, 02:10 UTC50m
2026-06-12 AUB129 AUO → AUO Jun 12, 16:45 UTCJun 12, 17:50 UTC1h 5m
2026-06-12 AUB129 AUO → AUO Jun 12, 01:50 UTCJun 12, 02:50 UTC1h 0m
2026-06-11 AUB129 AUO → AUO Jun 11, 16:30 UTCJun 11, 17:30 UTC1h 0m
2026-06-10 AUB129 - Jun 10, 22:25 UTCJun 10, 22:35 UTC10m
2026-06-10 AUB129 - Jun 10, 20:55 UTCJun 10, 21:20 UTC25m
2026-06-10 AUB129 AUO → AUO Jun 10, 02:05 UTCJun 10, 03:15 UTC1h 10m
2026-06-08 AUB129 - Jun 8, 21:35 UTCJun 8, 21:45 UTC10m
2026-06-08 AUB129 - Jun 8, 20:45 UTCJun 8, 21:00 UTC15m
2026-06-07 AUB129 AUO → AUO Jun 7, 01:35 UTCJun 7, 02:55 UTC1h 20m
2026-06-05 AUB129 AUO → AUO Jun 5, 19:55 UTCJun 5, 20:40 UTC45m
2026-06-05 AUB129 - Jun 5, 17:40 UTCJun 5, 17:50 UTC10m
2026-06-05 AUB129 - Jun 5, 16:50 UTCJun 5, 17:00 UTC10m
2026-06-05 AUB129 AUO → AUO Jun 5, 00:40 UTCJun 5, 02:45 UTC2h 5m
2026-06-04 AUB129 AUO → AUO Jun 4, 17:25 UTCJun 4, 18:35 UTC1h 10m
2026-06-04 AUB129 AUO → AUO Jun 4, 14:25 UTCJun 4, 14:30 UTC5m
2026-06-03 AUB129 AUO → AUO Jun 3, 22:35 UTCJun 3, 23:50 UTC1h 15m
2026-06-03 AUB129 - Jun 3, 13:25 UTCJun 3, 13:35 UTC10m
2026-06-03 AUB129 - Jun 3, 12:10 UTCJun 3, 12:20 UTC10m
2026-06-02 AUB129 AUO → AUO Jun 2, 21:50 UTCJun 2, 22:45 UTC55m
2026-06-02 AUB129 AUO → AUO Jun 2, 16:05 UTCJun 2, 17:10 UTC1h 5m
2026-06-01 AUB129 AUO → AUO Jun 1, 20:35 UTCJun 1, 21:30 UTC55m
2026-06-01 AUB129 AUO → AUO Jun 1, 17:00 UTCJun 1, 17:50 UTC50m
2026-05-29 AUB129 AUO → AUO May 29, 13:25 UTCMay 29, 14:30 UTC1h 5m
2026-05-28 AUB129 AUO → AUO May 28, 20:00 UTCMay 28, 20:35 UTC35m
2026-05-28 AUB129 AUO → AUO May 28, 15:40 UTCMay 28, 17:10 UTC1h 30m
2026-05-28 AUB129 - May 28, 03:50 UTCMay 28, 04:40 UTC50m
2026-05-28 AUB129 - May 28, 02:00 UTCMay 28, 02:45 UTC45m
2026-05-27 AUB129 AUO → AUO May 27, 14:45 UTCMay 27, 16:20 UTC1h 35m
2026-05-22 AUB129 AUO → AUO May 22, 17:35 UTCMay 22, 18:25 UTC50m
2026-05-14 AUB129 - May 14, 22:15 UTCMay 14, 22:35 UTC20m

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 N719TH page for operator, model, and routing details .

Mode-S A99F2D frequently asked

What is Mode-S code A99F2D?
A99F2D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N719TH.
Where is Mode-S A99F2D registered?
Mode-S code A99F2D 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 A99F2D broadcasting right now?
No active broadcast right now. Last signal was 11d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A99F2D, octal 52317455, decimal 11,116,333.
What flights does A99F2D operate?
Mode-S A99F2D has broadcast 1 distinct callsign, including AUB129.