sensors Mode-S transponder

AAB557

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N7897W · PIPER PA-28-140/150/160/180 · operated by DIMARIO CARMEN

Hex
AAB557
Octal
52532527
Decimal
11,187,543
Country
US
Tail
N7897W
Type
P28A
No current signal · last broadcast 4h ago
Flights observed
7
Distinct callsigns
1
Country
US
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S AAB557.

Country allocation

The ICAO 24-bit address AAB557 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
N7897W - 7 2026-05-30

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-05-30 N7897W - May 30, 00:40 UTCMay 30, 01:00 UTC20m
2026-05-29 N7897W - May 29, 22:15 UTCMay 29, 22:45 UTC30m
2026-05-16 N7897W - May 16, 23:40 UTCMay 17, 00:35 UTC55m
2026-05-16 N7897W - May 16, 21:25 UTCMay 16, 22:05 UTC40m
2026-05-10 N7897W - May 10, 00:49 UTCMay 10, 01:24 UTC35m
2026-05-09 N7897W - May 9, 15:15 UTCMay 9, 15:45 UTC30m
2026-04-25 N7897W - Apr 25, 14:55 UTCApr 25, 15:55 UTC1h 0m

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 N7897W page for operator, model, and routing details .

Mode-S AAB557 frequently asked

What is Mode-S code AAB557?
AAB557 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N7897W.
Where is Mode-S AAB557 registered?
Mode-S code AAB557 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 AAB557 broadcasting right now?
No active broadcast right now. Last signal was 4h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AAB557, octal 52532527, decimal 11,187,543.
What flights does AAB557 operate?
Mode-S AAB557 has broadcast 1 distinct callsign, including N7897W.