sensors Mode-S transponder
781B4B
ICAO 24-bit transponder address · allocated to China
Currently assigned to B-220R · BOEING 767-300
- Hex
- 781B4B
- Octal
- 36015513
- Decimal
- 7,871,307
- Country
- CN
- Tail
- B-220R
- Type
- B763
- Flights observed
- 141
- Distinct callsigns
- 20
- Country
- CN
- Last broadcast
- 6h ago
Last known position
Country allocation
The ICAO 24-bit address 781B4B 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 |
|---|---|---|---|
| CSS128 | - | 12 | 2026-07-03 |
| CSS127 | - | 11 | 2026-07-03 |
| CSS161 | - | 7 | 2026-06-30 |
| CSS148 | - | 7 | 2026-07-01 |
| CSS122 | - | 7 | 2026-06-26 |
| CSS121 | - | 7 | 2026-07-14 |
| CSS239 | SF Airlines | 6 | 2026-06-18 |
| CSS159 | - | 6 | 2026-06-28 |
| CSS240 | - | 5 | 2026-06-13 |
| CSS6802 | SF Airlines | 4 | 2026-06-05 |
| CSS254 | - | 4 | 2026-06-24 |
| CSS253 | - | 4 | 2026-06-24 |
| CSS173 | - | 4 | 2026-06-28 |
| CSS169 | - | 4 | 2026-07-05 |
| CSS155 | - | 4 | 2026-07-10 |
| CSS335 | SF Airlines | 3 | 2026-05-28 |
| CSS168 | SF Airlines | 3 | 2026-04-18 |
| CSS160 | - | 3 | 2026-06-29 |
| CSS7635 | - | 2 | 2026-07-09 |
| CSS6805 | SF Airlines | 2 | 2026-05-07 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-14 | CSS121 | - | Jul 14, 08:30 UTC | Jul 14, 08:40 UTC | 10m |
| 2026-07-12 | CSS7103 | - | Jul 12, 16:35 UTC | Jul 12, 16:50 UTC | 15m |
| 2026-07-11 | CSS7104 | - | Jul 11, 21:50 UTC | Jul 11, 22:05 UTC | 15m |
| 2026-07-11 | CSS156 | - | Jul 11, 11:30 UTC | Jul 11, 14:50 UTC | 3h 20m |
| 2026-07-10 | CSS155 | - | Jul 10, 16:55 UTC | Jul 11, 09:40 UTC | 16h 45m |
| 2026-07-09 | CSS7635 | - | Jul 9, 22:10 UTC | Jul 10, 17:15 UTC | 19h 5m |
| 2026-07-09 | CSS264 | - | Jul 9, 10:10 UTC | Jul 9, 22:15 UTC | 12h 5m |
| 2026-07-09 | CSS263 | - | Jul 9, 07:35 UTC | Jul 9, 08:10 UTC | 35m |
| 2026-07-05 | CSS169 | - | Jul 5, 10:45 UTC | Jul 5, 18:25 UTC | 7h 40m |
| 2026-07-03 | CSS128 | - | Jul 3, 18:55 UTC | Jul 4, 00:50 UTC | 5h 55m |
| 2026-07-03 | CSS127 | - | Jul 3, 07:15 UTC | Jul 3, 15:35 UTC | 8h 20m |
| 2026-07-02 | CSS127 | - | Jul 2, 18:50 UTC | Jul 3, 15:35 UTC | 20h 45m |
| 2026-07-02 | CSS170 | - | Jul 2, 17:25 UTC | Jul 3, 15:35 UTC | 22h 10m |
| 2026-07-02 | CSS170 | - | Jul 2, 12:50 UTC | Jul 3, 07:35 UTC | 18h 45m |
| 2026-07-02 | CSS169 | - | Jul 2, 11:00 UTC | Jul 3, 07:35 UTC | 20h 35m |
| 2026-07-01 | CSS169 | - | Jul 1, 16:50 UTC | Jul 2, 13:10 UTC | 20h 20m |
| 2026-07-01 | CSS169 | - | Jul 1, 16:20 UTC | Jul 2, 13:10 UTC | 20h 50m |
| 2026-07-01 | CSS148 | - | Jul 1, 00:10 UTC | Jul 1, 18:25 UTC | 18h 15m |
| 2026-06-30 | CSS161 | - | Jun 30, 19:35 UTC | Jun 30, 22:25 UTC | 2h 50m |
| 2026-06-29 | CSS160 | - | Jun 29, 14:04 UTC | Jun 29, 16:50 UTC | 2h 45m |
| 2026-06-28 | CSS159 | - | Jun 28, 21:10 UTC | Jun 29, 12:14 UTC | 15h 5m |
| 2026-06-28 | CSS173 | - | Jun 28, 00:39 UTC | Jun 28, 18:40 UTC | 18h 0m |
| 2026-06-27 | CSS161 | - | Jun 27, 09:15 UTC | Jun 27, 22:20 UTC | 13h 5m |
| 2026-06-26 | CSS122 | - | Jun 26, 14:50 UTC | Jun 27, 09:24 UTC | 18h 35m |
| 2026-06-26 | CSS121 | - | Jun 26, 05:19 UTC | Jun 26, 13:15 UTC | 7h 55m |
| 2026-06-24 | CSS254 | - | Jun 24, 07:05 UTC | Jun 24, 09:45 UTC | 2h 40m |
| 2026-06-24 | CSS253 | - | Jun 24, 02:54 UTC | Jun 24, 04:30 UTC | 1h 35m |
| 2026-06-20 | CSS7250 | - | Jun 20, 23:10 UTC | Jun 20, 23:25 UTC | 15m |
| 2026-06-19 | CSS122 | - | Jun 19, 15:49 UTC | Jun 19, 22:45 UTC | 6h 55m |
| 2026-06-19 | CSS121 | - | Jun 19, 11:59 UTC | Jun 19, 13:09 UTC | 1h 10m |
| 2026-06-18 | CSS148 | - | Jun 18, 14:50 UTC | Jun 19, 13:09 UTC | 22h 19m |
| 2026-06-18 | CSS148 | - | Jun 18, 14:10 UTC | Jun 19, 12:44 UTC | 22h 34m |
| 2026-06-18 | CSS239 | ZUH → DEL | Jun 18, 00:30 UTC | Jun 18, 12:20 UTC | 11h 50m |
| 2026-06-17 | CSS161 | - | Jun 17, 19:50 UTC | Jun 17, 22:15 UTC | 2h 25m |
| 2026-06-16 | CSS161 | - | Jun 16, 23:35 UTC | Jun 17, 22:15 UTC | 22h 40m |
| 2026-06-16 | CSS128 | - | Jun 16, 18:09 UTC | Jun 17, 00:20 UTC | 6h 11m |
| 2026-06-16 | CSS127 | - | Jun 16, 07:15 UTC | Jun 16, 15:24 UTC | 8h 10m |
| 2026-06-15 | CSS127 | - | Jun 15, 16:49 UTC | Jun 16, 15:24 UTC | 22h 35m |
| 2026-06-15 | CSS128 | - | Jun 15, 16:15 UTC | Jun 16, 14:45 UTC | 22h 30m |
| 2026-06-15 | CSS128 | - | Jun 15, 12:49 UTC | Jun 16, 07:40 UTC | 18h 50m |
| 2026-06-15 | CSS128 | - | Jun 15, 10:50 UTC | Jun 16, 07:40 UTC | 20h 50m |
| 2026-06-14 | CSS127 | - | Jun 14, 12:50 UTC | Jun 15, 07:25 UTC | 18h 34m |
| 2026-06-14 | CSS158 | DEL → EHU | Jun 14, 11:00 UTC | Jun 15, 07:25 UTC | 20h 25m |
| 2026-06-14 | CSS239 | ZUH → DEL | Jun 14, 04:25 UTC | Jun 14, 08:50 UTC | 4h 25m |
| 2026-06-13 | CSS240 | - | Jun 13, 21:00 UTC | Jun 13, 22:50 UTC | 1h 50m |
| 2026-06-13 | CSS159 | EHU → DEL | Jun 13, 16:20 UTC | Jun 13, 18:55 UTC | 2h 35m |
| 2026-06-13 | CSS159 | EHU → DEL | Jun 13, 00:00 UTC | Jun 13, 18:55 UTC | 18h 54m |
| 2026-06-12 | CSS159 | EHU → DEL | Jun 12, 21:35 UTC | Jun 13, 18:55 UTC | 21h 19m |
| 2026-06-12 | CSS128 | - | Jun 12, 18:50 UTC | Jun 13, 18:45 UTC | 23h 54m |
| 2026-06-12 | CSS128 | - | Jun 12, 18:25 UTC | Jun 13, 16:35 UTC | 22h 9m |
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-220R page for operator, model, and routing details .