Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A1A21F

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N204NV · AIRBUS A-320 · operated by UMB BANK NA TRUSTEE

Hex
A1A21F
Octal
50321037
Decimal
10,592,799
Country
US
Tail
N204NV
Type
A320
No current signal · last broadcast Jul 26, 21:45 UTC
Flights observed
337
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 21:45 UTC

Last known position

Most recent position reported by Mode-S A1A21F.

Country allocation

The ICAO 24-bit address A1A21F 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 20 distinct

Callsign Airline Flights Last seen
AAY1560 - 21 2026-07-22
AAY3185 - 17 2026-07-03
AAY3180 Allegiant Air 16 2026-07-26
AAY1557 Allegiant Air 15 2026-07-26
AAY1556 Allegiant Air 14 2026-07-26
AAY3183 Allegiant Air 13 2026-07-24
AAY3871 Allegiant Air 12 2026-07-25
AAY3188 - 12 2026-06-30
AAY1558 Allegiant Air 12 2026-07-16
AAY3870 Allegiant Air 11 2026-07-25
AAY3205 Allegiant Air 10 2026-05-30
AAY3202 Allegiant Air 9 2026-07-25
AAY1570 - 9 2026-07-03
AAY3204 - 7 2026-07-23
AAY3201 Allegiant Air 7 2026-07-23
AAY3200 Allegiant Air 7 2026-07-24
AAY1563 Allegiant Air 7 2026-07-23
AAY3206 Allegiant Air 6 2026-07-22
AAY3187 Allegiant Air 6 2026-07-26
AAY1562 Allegiant Air 6 2026-07-25

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 AAY3180 ATW → PIE Jul 26, 19:50 UTCJul 26, 21:45 UTC1h 55m
2026-07-26 AAY1557 BNA → ATW Jul 26, 15:50 UTCJul 26, 18:20 UTC2h 30m
2026-07-26 AAY1556 ATW → BNA Jul 26, 12:25 UTCJul 26, 14:35 UTC2h 10m
2026-07-26 AAY3187 ATW → FLL Jul 26, 03:00 UTCJul 26, 05:15 UTC2h 15m
2026-07-25 AAY3202 ATW → SFB Jul 25, 22:35 UTCJul 26, 00:30 UTC1h 55m
2026-07-25 AAY3871 PGD → ATW Jul 25, 17:50 UTCJul 25, 21:30 UTC3h 40m
2026-07-25 AAY3870 ATW → PGD Jul 25, 12:35 UTCJul 25, 16:20 UTC3h 45m
2026-07-25 AAY1562 BNA → ATW Jul 25, 01:35 UTCJul 25, 03:30 UTC1h 55m
2026-07-24 AAY1561 AZA → ATW Jul 24, 22:05 UTCJul 25, 00:20 UTC2h 15m
2026-07-24 AAY3200 AZA → ATW Jul 24, 17:30 UTCJul 24, 20:35 UTC3h 5m
2026-07-24 AAY3207 ATW → PGD Jul 24, 12:25 UTCJul 24, 16:15 UTC3h 50m
2026-07-24 AAY3183 PGD → ATW Jul 24, 00:15 UTCJul 24, 03:15 UTC3h 0m
2026-07-23 AAY1563 ATW → FLL Jul 23, 19:15 UTCJul 23, 22:30 UTC3h 15m
2026-07-23 AAY3201 PIE → ATW Jul 23, 16:10 UTCJul 23, 18:05 UTC1h 55m
2026-07-23 AAY3204 - Jul 23, 13:10 UTCJul 23, 14:50 UTC1h 40m
2026-07-23 AAY3209 ATW → PIE Jul 23, 00:45 UTCJul 23, 03:30 UTC2h 45m
2026-07-22 AAY3193 ATW → SFB Jul 22, 21:05 UTCJul 22, 23:30 UTC2h 25m
2026-07-22 AAY3206 ATW → FLL Jul 22, 16:55 UTCJul 22, 20:00 UTC3h 5m
2026-07-22 AAY1560 - Jul 22, 12:10 UTCJul 22, 15:35 UTC3h 25m
2026-07-21 AAY1562 BNA → ATW Jul 21, 02:05 UTCJul 21, 03:55 UTC1h 50m
2026-07-20 AAY1561 AZA → ATW Jul 20, 22:05 UTCJul 21, 00:20 UTC2h 15m
2026-07-20 AAY3200 AZA → ATW Jul 20, 17:40 UTCJul 20, 20:35 UTC2h 55m
2026-07-20 AAY3182 ATW → PDX Jul 20, 12:35 UTCJul 20, 16:35 UTC4h 0m
2026-07-20 AAY3183 PGD → ATW Jul 20, 00:10 UTCJul 20, 03:15 UTC3h 5m
2026-07-19 AAY1563 ATW → FLL Jul 19, 19:45 UTCJul 19, 22:55 UTC3h 10m
2026-07-19 AAY3201 PIE → ATW Jul 19, 16:25 UTCJul 19, 18:40 UTC2h 15m
2026-07-19 AAY3204 - Jul 19, 13:10 UTCJul 19, 14:50 UTC1h 40m
2026-07-19 AAY3187 ATW → FLL Jul 19, 03:55 UTCJul 19, 06:00 UTC2h 5m
2026-07-19 AAY3202 ATW → SFB Jul 19, 00:30 UTCJul 19, 02:30 UTC2h 0m
2026-07-18 AAY3871 PGD → ATW Jul 18, 19:25 UTCJul 18, 23:05 UTC3h 40m
2026-07-18 AAY3870 - Jul 18, 12:35 UTCJul 18, 16:10 UTC3h 35m
2026-07-18 AAY1562 DEN → ATW Jul 18, 01:25 UTCJul 18, 03:40 UTC2h 16m
2026-07-17 AAY1561 - Jul 17, 22:15 UTCJul 18, 00:15 UTC2h 0m
2026-07-17 AAY3200 PDX → ATW Jul 17, 17:44 UTCJul 17, 21:05 UTC3h 20m
2026-07-17 AAY3207 ATW → PGD Jul 17, 12:35 UTCJul 17, 16:10 UTC3h 35m
2026-07-16 AAY1558 ALB → PGD Jul 16, 23:44 UTCJul 17, 02:15 UTC2h 30m
2026-07-16 AAY3180 ATW → MCO Jul 16, 19:50 UTCJul 16, 22:25 UTC2h 35m
2026-07-16 AAY1557 - Jul 16, 16:00 UTCJul 16, 18:19 UTC2h 20m
2026-07-16 AAY1556 - Jul 16, 12:25 UTCJul 16, 14:35 UTC2h 10m
2026-07-16 AAY3209 - Jul 16, 00:40 UTCJul 16, 03:10 UTC2h 30m
2026-07-15 AAY3193 - Jul 15, 21:05 UTCJul 15, 23:35 UTC2h 30m
2026-07-15 AAY3206 LAS → ATW Jul 15, 16:50 UTCJul 15, 20:00 UTC3h 10m
2026-07-15 AAY1560 ATW → LAS Jul 15, 12:10 UTCJul 15, 15:20 UTC3h 10m
2026-07-14 AAY1562 DEN → ATW Jul 14, 02:10 UTCJul 14, 04:20 UTC2h 10m
2026-07-13 AAY1561 ATW → DEN Jul 13, 22:20 UTCJul 14, 00:10 UTC1h 50m
2026-07-13 AAY3200 PDX → ATW Jul 13, 17:20 UTCJul 13, 20:40 UTC3h 20m
2026-07-13 AAY3182 ATW → PDX Jul 13, 12:25 UTCJul 13, 16:00 UTC3h 35m
2026-07-13 AAY1558 MCO → ATW Jul 13, 00:35 UTCJul 13, 03:15 UTC2h 40m
2026-07-12 AAY3180 ATW → MCO Jul 12, 20:01 UTCJul 12, 22:30 UTC2h 30m
2026-07-12 AAY1557 - Jul 12, 15:55 UTCJul 12, 18:05 UTC2h 10m

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 N204NV page for operator, model, and routing details .

Mode-S A1A21F frequently asked

What is Mode-S code A1A21F?
A1A21F is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N204NV.
Where is Mode-S A1A21F registered?
Mode-S code A1A21F 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 A1A21F broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:45 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1A21F, octal 50321037, decimal 10,592,799.
What flights does A1A21F operate?
Mode-S A1A21F has broadcast 20 distinct callsigns, including AAY1560, AAY3185, AAY3180, AAY1557, AAY1556.