sensors Mode-S transponder

7817FB

ICAO 24-bit transponder address · allocated to China

Currently assigned to B-20DT · BOEING 787-9 Dreamliner

Hex
7817FB
Octal
36013773
Decimal
7,870,459
Country
CN
Tail
B-20DT
Type
B789
No current signal · last broadcast 1d ago
Flights observed
4
Distinct callsigns
4
Country
CN
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 7817FB.

Country allocation

The ICAO 24-bit address 7817FB falls within the block assigned to China (CN) by ICAO Annex 10, Volume III. Every aircraft registered in China 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 4 distinct

Callsign Airline Flights Last seen
DKH1670 - 1 2026-04-13
DKH1669 Juneyao Airlines 1 2026-04-12
DKH1338 - 1 2026-04-13
DKH1337 - 1 2026-04-13

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-13 DKH1338 - Apr 13, 13:50 UTCApr 13, 14:30 UTC40m
2026-04-13 DKH1337 - Apr 13, 11:15 UTCApr 13, 11:40 UTC25m
2026-04-13 DKH1670 - Apr 13, 05:40 UTCApr 13, 07:50 UTC2h 10m
2026-04-12 DKH1669 PVG → SYD Apr 12, 19:05 UTCApr 12, 20:10 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 B-20DT page for operator, model, and routing details .

Mode-S 7817FB frequently asked

What is Mode-S code 7817FB?
7817FB is an ICAO 24-bit transponder address. Allocated to China. Assigned to B-20DT.
Where is Mode-S 7817FB registered?
Mode-S code 7817FB is allocated to China (CN). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 7817FB 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 7817FB, octal 36013773, decimal 7,870,459.
What flights does 7817FB operate?
Mode-S 7817FB has broadcast 4 distinct callsigns, including DKH1670, DKH1669, DKH1338, DKH1337.