sensors Mode-S transponder

A0998A

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N138GL · GULFSTREAM 5 · operated by SWR SERVICES III LLC

Hex
A0998A
Octal
50114612
Decimal
10,525,066
Country
US
Tail
N138GL
Type
GLF5
No current signal · last broadcast 23h ago
Flights observed
35
Distinct callsigns
2
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A0998A.

Country allocation

The ICAO 24-bit address A0998A 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 2 distinct

Callsign Airline Flights Last seen
N138GL - 33 2026-05-28
TWY4 - 2 2026-05-29

Recent flights last 35

DateFlightRouteTakeoffLandingDuration
2026-05-29 TWY4 NCE → LTN May 29, 08:05 UTCMay 29, 09:35 UTC1h 30m
2026-05-28 TWY4 - May 28, 20:35 UTCMay 29, 07:10 UTC10h 35m
2026-05-28 N138GL - May 28, 04:40 UTCMay 28, 08:15 UTC3h 35m
2026-05-27 N138GL OAK → MDW May 27, 23:40 UTCMay 28, 03:00 UTC3h 20m
2026-05-23 N138GL - May 23, 02:10 UTCMay 23, 07:00 UTC4h 49m
2026-05-22 N138GL TEB → TTN May 22, 23:50 UTCMay 23, 00:05 UTC15m
2026-05-21 N138GL BFI → TEB May 21, 17:50 UTCMay 21, 21:55 UTC4h 5m
2026-05-21 N138GL - May 21, 13:55 UTCMay 21, 15:25 UTC1h 30m
2026-05-18 N138GL - May 18, 21:35 UTCMay 19, 02:50 UTC5h 15m
2026-05-17 N138GL OAK → TEB May 17, 22:55 UTCMay 18, 03:30 UTC4h 35m
2026-05-17 N138GL BUR → OAK May 17, 21:35 UTCMay 17, 22:25 UTC50m
2026-05-15 N138GL OAK → BUR May 15, 21:50 UTCMay 15, 22:40 UTC50m
2026-05-14 N138GL PBI → OAK May 14, 16:40 UTCMay 14, 21:50 UTC5h 10m
2026-05-14 N138GL - May 14, 10:25 UTCMay 14, 12:30 UTC2h 5m
2026-05-13 N138GL - May 13, 02:40 UTCMay 13, 04:50 UTC2h 10m
2026-05-11 N138GL OAK → XNA May 11, 11:30 UTCMay 11, 14:15 UTC2h 45m
2026-05-10 N138GL SBA → OAK May 10, 22:20 UTCMay 10, 23:09 UTC50m
2026-05-08 N138GL OAK → SBA May 8, 23:00 UTCMay 8, 23:45 UTC45m
2026-05-07 N138GL SBA → OAK May 7, 03:45 UTCMay 7, 04:30 UTC45m
2026-05-06 N138GL OAK → SBA May 6, 23:40 UTCMay 7, 00:25 UTC45m
2026-05-03 N138GL BUR → OAK May 3, 20:49 UTCMay 3, 21:39 UTC50m
2026-05-03 N138GL OAK → BUR May 3, 14:35 UTCMay 3, 15:30 UTC55m
2026-04-30 N138GL BUR → OAK Apr 30, 02:00 UTCApr 30, 02:50 UTC50m
2026-04-28 N138GL - Apr 28, 21:55 UTCApr 29, 03:04 UTC5h 10m
2026-04-26 N138GL OAK → TEB Apr 26, 23:25 UTCApr 27, 03:45 UTC4h 20m
2026-04-22 N138GL - Apr 22, 01:35 UTCApr 22, 06:35 UTC5h 0m
2026-04-19 N138GL - Apr 19, 23:00 UTCApr 20, 03:15 UTC4h 15m
2026-04-19 N138GL BUR → OAK Apr 19, 21:40 UTCApr 19, 22:25 UTC45m
2026-04-19 N138GL OAK → BUR Apr 19, 05:10 UTCApr 19, 06:05 UTC55m
2026-04-18 N138GL BUR → OAK Apr 18, 23:25 UTCApr 19, 00:15 UTC50m
2026-04-17 N138GL - Apr 17, 23:25 UTCApr 18, 00:00 UTC35m
2026-04-17 N138GL - Apr 17, 23:10 UTCApr 17, 23:20 UTC10m
2026-04-16 N138GL BUR → OAK Apr 16, 01:15 UTCApr 16, 02:09 UTC55m
2026-04-15 N138GL OAK → BUR Apr 15, 23:40 UTCApr 16, 00:30 UTC50m
2026-04-13 N138GL BUR → OAK Apr 13, 00:25 UTCApr 13, 01:20 UTC55m

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 N138GL page for operator, model, and routing details .

Mode-S A0998A frequently asked

What is Mode-S code A0998A?
A0998A is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N138GL.
Where is Mode-S A0998A registered?
Mode-S code A0998A 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 A0998A broadcasting right now?
No active broadcast right now. Last signal was 23h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A0998A, octal 50114612, decimal 10,525,066.
What flights does A0998A operate?
Mode-S A0998A has broadcast 2 distinct callsigns, including N138GL, TWY4.