sensors Mode-S transponder

781E2B

ICAO 24-bit transponder address · allocated to China

Currently assigned to B-222J · BOEING 777-200LR

Hex
781E2B
Octal
36017053
Decimal
7,872,043
Country
CN
Tail
B-222J
Type
B77L
No current signal · last broadcast Jul 26, 21:55 UTC
Flights observed
223
Distinct callsigns
20
Country
CN
Last broadcast
Jul 26, 21:55 UTC

Last known position

Most recent position reported by Mode-S 781E2B.

Country allocation

The ICAO 24-bit address 781E2B 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 20 distinct

Callsign Airline Flights Last seen
CKK227 China Cargo Airlines 25 2026-06-29
CKK225 - 17 2026-07-13
CKK222 - 15 2026-07-18
CKK221 China Cargo Airlines 15 2026-07-26
CKK205 China Cargo Airlines 13 2026-07-24
CKK236 - 11 2026-06-24
CKK235 - 11 2026-06-24
CKK231 - 11 2026-07-19
CKK206 China Cargo Airlines 11 2026-07-25
CKK228 - 10 2026-06-29
CKK203 - 9 2026-07-15
CKK223 China Cargo Airlines 8 2026-05-31
CKK602 - 7 2026-06-25
CKK601 - 7 2026-06-25
CKK204 - 6 2026-07-15
CKK606 - 5 2026-07-23
CKK226 - 5 2026-07-13
CKK288 - 4 2026-07-03
CKK232 - 4 2026-07-19
CKK224 China Cargo Airlines 4 2026-06-01

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 CKK221 PVG → LAX Jul 26, 10:45 UTCJul 26, 21:55 UTC11h 10m
2026-07-25 CKK221 PVG → LAX Jul 25, 21:50 UTCJul 26, 20:45 UTC22h 56m
2026-07-25 CKK206 AMS → PVG Jul 25, 16:50 UTCJul 26, 12:30 UTC19h 41m
2026-07-25 CKK206 AMS → PVG Jul 25, 16:30 UTCJul 26, 12:30 UTC20h 1m
2026-07-24 CKK205 PVG → AMS Jul 24, 21:40 UTCJul 25, 13:40 UTC16h 0m
2026-07-24 CKK257 PVG → ICN Jul 24, 18:35 UTCJul 24, 19:20 UTC45m
2026-07-23 CKK257 PVG → ICN Jul 23, 20:55 UTCJul 24, 19:20 UTC22h 25m
2026-07-23 CKK606 - Jul 23, 11:40 UTCJul 23, 21:05 UTC9h 25m
2026-07-23 CKK605 - Jul 23, 01:50 UTCJul 23, 08:20 UTC6h 30m
2026-07-19 CKK232 - Jul 19, 21:30 UTCJul 20, 11:10 UTC13h 40m
2026-07-19 CKK231 - Jul 19, 09:45 UTCJul 19, 16:00 UTC6h 15m
2026-07-19 CKK231 - Jul 19, 00:45 UTCJul 19, 08:10 UTC7h 25m
2026-07-18 CKK231 - Jul 18, 10:50 UTCJul 19, 08:10 UTC21h 20m
2026-07-18 CKK231 - Jul 18, 10:20 UTCJul 19, 08:10 UTC21h 50m
2026-07-18 CKK222 - Jul 18, 00:55 UTCJul 19, 00:45 UTC23h 51m
2026-07-17 CKK221 - Jul 17, 02:50 UTCJul 17, 22:20 UTC19h 30m
2026-07-17 CKK221 - Jul 17, 01:25 UTCJul 17, 22:20 UTC20h 55m
2026-07-16 CKK241 - Jul 16, 21:15 UTCJul 16, 22:59 UTC1h 45m
2026-07-15 CKK204 - Jul 15, 13:05 UTCJul 15, 19:40 UTC6h 35m
2026-07-15 CKK203 - Jul 15, 02:30 UTCJul 15, 09:15 UTC6h 45m
2026-07-14 CKK203 - Jul 14, 04:50 UTCJul 15, 03:15 UTC22h 24m
2026-07-13 CKK226 - Jul 13, 15:50 UTCJul 14, 04:50 UTC13h 0m
2026-07-13 CKK225 ANC → ORD Jul 13, 07:01 UTCJul 13, 12:25 UTC5h 25m
2026-07-12 CKK225 - Jul 12, 22:35 UTCJul 13, 05:55 UTC7h 20m
2026-07-12 CKK225 - Jul 12, 06:40 UTCJul 13, 04:40 UTC22h 0m
2026-07-12 CKK225 - Jul 12, 03:20 UTCJul 13, 00:15 UTC20h 55m
2026-07-12 CKK606 - Jul 12, 00:50 UTCJul 13, 00:15 UTC23h 25m
2026-07-11 CKK606 - Jul 11, 22:50 UTCJul 12, 22:45 UTC23h 55m
2026-07-11 CKK606 - Jul 11, 21:45 UTCJul 12, 06:45 UTC9h 0m
2026-07-11 CKK605 - Jul 11, 01:40 UTCJul 11, 08:20 UTC6h 40m
2026-07-10 CKK278 - Jul 10, 04:45 UTCJul 10, 05:05 UTC20m
2026-07-09 CKK222 - Jul 9, 10:30 UTCJul 10, 01:35 UTC15h 5m
2026-07-09 CKK222 - Jul 9, 00:50 UTCJul 9, 23:50 UTC23h 0m
2026-07-09 CKK222 - Jul 9, 00:20 UTCJul 9, 12:25 UTC12h 5m
2026-07-08 CKK221 PVG → LAX Jul 8, 10:55 UTCJul 8, 21:45 UTC10h 50m
2026-07-07 CKK206 AMS → PVG Jul 7, 16:20 UTCJul 7, 22:15 UTC5h 55m
2026-07-07 CKK205 - Jul 7, 07:05 UTCJul 7, 13:40 UTC6h 35m
2026-07-04 CKK226 - Jul 4, 20:35 UTCJul 5, 09:30 UTC12h 55m
2026-07-04 CKK225 PVG → LAX Jul 4, 10:10 UTCJul 4, 15:45 UTC5h 35m
2026-07-03 CKK225 PVG → LAX Jul 3, 16:25 UTCJul 4, 08:30 UTC16h 5m
2026-07-03 CKK288 - Jul 3, 10:40 UTCJul 3, 14:00 UTC3h 20m
2026-07-02 CKK287 - Jul 2, 14:25 UTCJul 3, 08:25 UTC18h 0m
2026-07-02 CKK232 - Jul 2, 01:25 UTCJul 2, 15:05 UTC13h 40m
2026-07-01 CKK231 ANC → JFK Jul 1, 15:40 UTCJul 1, 22:20 UTC6h 40m
2026-06-30 CKK231 - Jun 30, 22:50 UTCJul 1, 14:20 UTC15h 30m
2026-06-29 CKK257 - Jun 29, 22:49 UTCJun 30, 17:55 UTC19h 6m
2026-06-29 CKK228 - Jun 29, 21:19 UTCJun 30, 17:55 UTC20h 36m
2026-06-29 CKK227 PVG → ANC Jun 29, 12:39 UTCJun 29, 18:25 UTC5h 45m
2026-06-29 CKK227 PVG → ANC Jun 29, 04:00 UTCJun 29, 11:14 UTC7h 15m
2026-06-28 CKK227 PVG → ANC Jun 28, 15:05 UTCJun 29, 11:14 UTC20h 10m

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-222J page for operator, model, and routing details .

Mode-S 781E2B frequently asked

What is Mode-S code 781E2B?
781E2B is an ICAO 24-bit transponder address. Allocated to China. Assigned to B-222J.
Where is Mode-S 781E2B registered?
Mode-S code 781E2B is allocated to China (CN). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 781E2B broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:55 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 781E2B, octal 36017053, decimal 7,872,043.
What flights does 781E2B operate?
Mode-S 781E2B has broadcast 20 distinct callsigns, including CKK227, CKK225, CKK222, CKK221, CKK205.