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sensors Mode-S transponder

A991F4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N7157G · CESSNA 172 Skyhawk · operated by AERO QUEST LLC, SAINT-GILLES LLC

Hex
A991F4
Octal
52310764
Decimal
11,112,948
Country
US
Tail
N7157G
Type
C172
No current signal · last broadcast 2h ago
Flights observed
199
Distinct callsigns
1
Country
US
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S A991F4.

Country allocation

The ICAO 24-bit address A991F4 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
N7157G - 199 2026-07-14

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 N7157G - Jul 14, 17:50 UTCJul 14, 18:30 UTC40m
2026-07-14 N7157G - Jul 14, 11:55 UTCJul 14, 12:40 UTC45m
2026-07-14 N7157G OLV → OLV Jul 14, 00:10 UTCJul 14, 00:50 UTC40m
2026-07-13 N7157G - Jul 13, 21:45 UTCJul 13, 22:45 UTC1h 0m
2026-07-13 N7157G - Jul 13, 20:40 UTCJul 13, 20:50 UTC10m
2026-07-13 N7157G - Jul 13, 19:40 UTCJul 13, 20:00 UTC20m
2026-07-13 N7157G OLV → OLV Jul 13, 17:40 UTCJul 13, 18:15 UTC35m
2026-07-13 N7157G - Jul 13, 13:55 UTCJul 13, 14:15 UTC20m
2026-07-13 N7157G OLV → OLV Jul 13, 12:05 UTCJul 13, 12:50 UTC45m
2026-07-12 N7157G OLV → OLV Jul 12, 19:40 UTCJul 12, 20:40 UTC1h 0m
2026-07-11 N7157G OLV → OLV Jul 11, 17:45 UTCJul 11, 18:25 UTC40m
2026-07-11 N7157G - Jul 11, 16:25 UTCJul 11, 16:45 UTC20m
2026-07-11 N7157G - Jul 11, 15:40 UTCJul 11, 15:50 UTC10m
2026-07-10 N7157G - Jul 10, 21:30 UTCJul 10, 22:20 UTC50m
2026-07-10 N7157G OLV → OLV Jul 10, 16:00 UTCJul 10, 16:30 UTC30m
2026-07-10 N7157G - Jul 10, 13:30 UTCJul 10, 14:15 UTC45m
2026-07-09 N7157G - Jul 9, 21:55 UTCJul 9, 23:00 UTC1h 5m
2026-07-09 N7157G - Jul 9, 20:50 UTCJul 9, 21:05 UTC15m
2026-07-09 N7157G - Jul 9, 19:35 UTCJul 9, 19:50 UTC15m
2026-07-09 N7157G - Jul 9, 17:45 UTCJul 9, 18:55 UTC1h 10m
2026-07-09 N7157G - Jul 9, 16:05 UTCJul 9, 16:45 UTC40m
2026-07-08 N7157G - Jul 8, 15:35 UTCJul 8, 16:15 UTC40m
2026-07-08 N7157G - Jul 8, 11:45 UTCJul 8, 13:05 UTC1h 20m
2026-07-07 N7157G - Jul 7, 21:05 UTCJul 7, 21:25 UTC20m
2026-07-07 N7157G - Jul 7, 17:10 UTCJul 7, 17:35 UTC25m
2026-07-07 N7157G - Jul 7, 15:30 UTCJul 7, 15:45 UTC15m
2026-07-07 N7157G - Jul 7, 14:05 UTCJul 7, 14:35 UTC30m
2026-07-07 N7157G - Jul 7, 11:50 UTCJul 7, 13:05 UTC1h 15m
2026-07-06 N7157G - Jul 6, 19:30 UTCJul 6, 19:55 UTC25m
2026-07-04 N7157G - Jul 4, 14:50 UTCJul 4, 15:40 UTC50m
2026-07-03 N7157G OLV → OLV Jul 3, 11:40 UTCJul 3, 12:50 UTC1h 10m
2026-07-02 N7157G OLV → OLV Jul 2, 21:55 UTCJul 2, 22:30 UTC35m
2026-06-30 N7157G - Jun 30, 16:00 UTCJun 30, 16:50 UTC50m
2026-06-30 N7157G - Jun 30, 13:50 UTCJun 30, 14:30 UTC40m
2026-06-29 N7157G - Jun 29, 22:49 UTCJun 29, 22:59 UTC10m
2026-06-29 N7157G - Jun 29, 21:05 UTCJun 29, 21:19 UTC15m
2026-06-29 N7157G OLV → OLV Jun 29, 15:24 UTCJun 29, 16:15 UTC50m
2026-06-29 N7157G - Jun 29, 11:45 UTCJun 29, 12:49 UTC1h 5m
2026-06-26 N7157G - Jun 26, 19:14 UTCJun 26, 19:30 UTC15m
2026-06-26 N7157G - Jun 26, 18:24 UTCJun 26, 18:39 UTC15m
2026-06-26 N7157G - Jun 26, 16:05 UTCJun 26, 16:44 UTC40m
2026-06-26 N7157G - Jun 26, 13:49 UTCJun 26, 14:29 UTC40m
2026-06-25 N7157G - Jun 25, 22:29 UTCJun 25, 22:49 UTC20m
2026-06-25 N7157G OLV → OLV Jun 25, 19:34 UTCJun 25, 20:14 UTC40m
2026-06-25 N7157G - Jun 25, 17:30 UTCJun 25, 18:10 UTC40m
2026-06-25 N7157G - Jun 25, 15:50 UTCJun 25, 16:45 UTC55m
2026-06-25 N7157G - Jun 25, 13:35 UTCJun 25, 15:04 UTC1h 30m
2026-06-24 N7157G - Jun 24, 21:09 UTCJun 24, 21:50 UTC40m
2026-06-24 N7157G - Jun 24, 19:39 UTCJun 24, 20:14 UTC35m
2026-06-24 N7157G - Jun 24, 17:45 UTCJun 24, 18:39 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 N7157G page for operator, model, and routing details .

Mode-S A991F4 frequently asked

What is Mode-S code A991F4?
A991F4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N7157G.
Where is Mode-S A991F4 registered?
Mode-S code A991F4 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 A991F4 broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A991F4, octal 52310764, decimal 11,112,948.
What flights does A991F4 operate?
Mode-S A991F4 has broadcast 1 distinct callsign, including N7157G.