sensors Mode-S transponder
781DD2
ICAO 24-bit transponder address · allocated to China
Currently assigned to B-651V · COMAC ARJ-21-700 Xiangfeng
- Hex
- 781DD2
- Octal
- 36016722
- Decimal
- 7,871,954
- Country
- CN
- Tail
- B-651V
- Type
- AJ27
- Flights observed
- 13
- Distinct callsigns
- 8
- Country
- CN
- Last broadcast
- Jul 24, 00:40 UTC
Last known position
Country allocation
The ICAO 24-bit address 781DD2 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 8 distinct
| Callsign | Airline | Flights | Last seen |
|---|---|---|---|
| CES9147 | China Eastern Airlines | 4 | 2026-07-24 |
| CES9128 | - | 2 | 2026-07-18 |
| CES9127 | - | 2 | 2026-07-18 |
| CES9149 | - | 1 | 2026-07-21 |
| CES9148 | China Eastern Airlines | 1 | 2026-07-21 |
| CES9138 | - | 1 | 2026-06-24 |
| CES9129 | - | 1 | 2026-07-22 |
| CES9119 | - | 1 | 2026-05-30 |
Recent flights last 13
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-24 | CES9147 | PVG → NDG | Jul 24, 00:25 UTC | Jul 24, 00:40 UTC | 15m |
| 2026-07-22 | CES9129 | - | Jul 22, 11:50 UTC | Jul 23, 04:10 UTC | 16h 20m |
| 2026-07-21 | CES9148 | NDG → PVG | Jul 21, 12:10 UTC | Jul 21, 12:25 UTC | 15m |
| 2026-07-21 | CES9149 | - | Jul 21, 05:30 UTC | Jul 21, 05:40 UTC | 10m |
| 2026-07-21 | CES9147 | PVG → NDG | Jul 21, 00:30 UTC | Jul 21, 00:50 UTC | 20m |
| 2026-07-20 | CES9147 | PVG → NDG | Jul 20, 00:30 UTC | Jul 20, 01:00 UTC | 30m |
| 2026-07-18 | CES9128 | - | Jul 18, 13:40 UTC | Jul 18, 13:55 UTC | 15m |
| 2026-07-18 | CES9127 | - | Jul 18, 11:25 UTC | Jul 18, 11:45 UTC | 20m |
| 2026-06-29 | CES9147 | - | Jun 29, 00:34 UTC | Jun 29, 00:49 UTC | 15m |
| 2026-06-24 | CES9138 | - | Jun 24, 09:24 UTC | Jun 24, 09:39 UTC | 15m |
| 2026-05-30 | CES9119 | - | May 30, 04:40 UTC | May 30, 05:00 UTC | 20m |
| 2026-05-24 | CES9128 | - | May 24, 09:55 UTC | May 24, 10:15 UTC | 20m |
| 2026-05-24 | CES9127 | - | May 24, 05:40 UTC | May 24, 07:40 UTC | 2h 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 B-651V page for operator, model, and routing details .