sensors Mode-S transponder

AC1CDE

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N88QD · PILATUS PC-12 · operated by QUEST DIAGNOSTICS CLINICAL LABORATORIES INC

Hex
AC1CDE
Octal
53016336
Decimal
11,279,582
Country
US
Tail
N88QD
Type
PC12
No current signal · last broadcast 18h ago
Flights observed
2
Distinct callsigns
1
Country
US
Last broadcast
18h ago

Last known position

Most recent position reported by Mode-S AC1CDE.

Country allocation

The ICAO 24-bit address AC1CDE 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
LBQ870 - 2 2026-04-14

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-14 LBQ870 ROA → MNZ Apr 14, 10:25 UTCApr 14, 11:05 UTC40m
2026-04-14 LBQ870 - Apr 14, 09:10 UTCApr 14, 10:15 UTC1h 5m

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 N88QD page for operator, model, and routing details .

Mode-S AC1CDE frequently asked

What is Mode-S code AC1CDE?
AC1CDE is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N88QD.
Where is Mode-S AC1CDE registered?
Mode-S code AC1CDE 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 AC1CDE broadcasting right now?
No active broadcast right now. Last signal was 18h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AC1CDE, octal 53016336, decimal 11,279,582.
What flights does AC1CDE operate?
Mode-S AC1CDE has broadcast 1 distinct callsign, including LBQ870.