sensors Mode-S transponder

A99AFB

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N718NK · operated by WILMINGTON TRUST CO TRUSTEE

Hex
A99AFB
Octal
52315373
Decimal
11,115,259
Country
US
Tail
N718NK
Type
A21N
No current signal · last broadcast 13h ago
Flights observed
7
Distinct callsigns
7
Country
US
Last broadcast
13h ago

Last known position

Most recent position reported by Mode-S A99AFB.

Country allocation

The ICAO 24-bit address A99AFB 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 7 distinct

Callsign Airline Flights Last seen
NKS995 - 1 2026-04-13
NKS988 - 1 2026-04-13
NKS982 - 1 2026-04-12
NKS352 - 1 2026-04-13
NKS250 Spirit Airlines 1 2026-04-14
NKS1173 - 1 2026-04-12
NKS1000 - 1 2026-04-13

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-14 NKS250 BDL → RSW Apr 14, 10:00 UTCApr 14, 11:05 UTC1h 5m
2026-04-13 NKS988 - Apr 13, 16:15 UTCApr 13, 17:45 UTC1h 30m
2026-04-13 NKS352 - Apr 13, 13:05 UTCApr 13, 14:45 UTC1h 40m
2026-04-13 NKS1000 - Apr 13, 04:26 UTCApr 13, 05:33 UTC1h 7m
2026-04-13 NKS995 LGA → DTW Apr 13, 01:23 UTCApr 13, 02:46 UTC1h 23m
2026-04-12 NKS982 - Apr 12, 23:55 UTCApr 13, 00:05 UTC10m
2026-04-12 NKS1173 DFW → MCO Apr 12, 17:17 UTCApr 12, 19:34 UTC2h 17m

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 N718NK page for operator, model, and routing details .

Mode-S A99AFB frequently asked

What is Mode-S code A99AFB?
A99AFB is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N718NK.
Where is Mode-S A99AFB registered?
Mode-S code A99AFB 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 A99AFB broadcasting right now?
No active broadcast right now. Last signal was 13h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A99AFB, octal 52315373, decimal 11,115,259.
What flights does A99AFB operate?
Mode-S A99AFB has broadcast 7 distinct callsigns, including NKS995, NKS988, NKS982, NKS352, NKS250.