sensors Mode-S transponder

A74D57

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N57PB · CESSNA 402 Businessliner · operated by HYANNIS AIR SERVICE INC DBA, CAPE AIR

Hex
A74D57
Octal
51646527
Decimal
10,964,311
Country
US
Tail
N57PB
Type
C402
No current signal · last broadcast 1d ago
Flights observed
8
Distinct callsigns
3
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A74D57.

Country allocation

The ICAO 24-bit address A74D57 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 3 distinct

Callsign Airline Flights Last seen
KAP115 - 4 2026-04-13
KAP1834 - 2 2026-04-13
KAP1830 Cape Air 2 2026-04-13

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 KAP115 - Apr 13, 20:40 UTCApr 13, 21:50 UTC1h 10m
2026-04-13 KAP1834 - Apr 13, 16:20 UTCApr 13, 17:30 UTC1h 10m
2026-04-13 KAP115 - Apr 13, 13:45 UTCApr 13, 14:55 UTC1h 10m
2026-04-13 KAP115 - Apr 13, 12:20 UTCApr 13, 12:30 UTC10m
2026-04-13 KAP1830 BHB → BOS Apr 13, 11:55 UTCApr 13, 12:30 UTC35m
2026-04-13 KAP1830 BHB → BOS Apr 13, 11:10 UTCApr 13, 12:15 UTC1h 5m
2026-04-12 KAP115 - Apr 12, 19:55 UTCApr 12, 20:15 UTC20m
2026-04-12 KAP1834 - Apr 12, 17:15 UTCApr 12, 17:30 UTC15m

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 N57PB page for operator, model, and routing details .

Mode-S A74D57 frequently asked

What is Mode-S code A74D57?
A74D57 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N57PB.
Where is Mode-S A74D57 registered?
Mode-S code A74D57 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 A74D57 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A74D57, octal 51646527, decimal 10,964,311.
What flights does A74D57 operate?
Mode-S A74D57 has broadcast 3 distinct callsigns, including KAP115, KAP1834, KAP1830.