sensors Mode-S transponder
78221B
ICAO 24-bit transponder address · allocated to China
Currently assigned to B-227F · BOEING 737-800
- Hex
- 78221B
- Octal
- 36021033
- Decimal
- 7,873,051
- Country
- CN
- Tail
- B-227F
- Type
- B738
- Flights observed
- 41
- Distinct callsigns
- 17
- Country
- CN
- Last broadcast
- 2h ago
Last known position
Country allocation
The ICAO 24-bit address 78221B 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 17 distinct
| Callsign | Airline | Flights | Last seen |
|---|---|---|---|
| CSS6807 | - | 10 | 2026-07-14 |
| CSS6808 | - | 6 | 2026-07-15 |
| CSS6814 | - | 4 | 2026-07-03 |
| CSS6802 | SF Airlines | 4 | 2026-07-20 |
| CSS7109 | SF Airlines | 2 | 2026-07-22 |
| CSS6805 | - | 2 | 2026-07-04 |
| CSS6804 | - | 2 | 2026-07-04 |
| CSS6803 | - | 2 | 2026-07-16 |
| CSS7110 | SF Airlines | 1 | 2026-07-21 |
| CSS7088 | - | 1 | 2026-06-20 |
| CSS6831 | - | 1 | 2026-04-17 |
| CSS6813 | - | 1 | 2026-07-02 |
| CSS6810 | - | 1 | 2026-06-03 |
| CSS6809 | - | 1 | 2026-06-04 |
| CSS6806 | SF Airlines | 1 | 2026-05-16 |
| CSS3014 | - | 1 | 2026-07-10 |
| CSS3001 | - | 1 | 2026-05-18 |
Recent flights last 41
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-22 | CSS7109 | PEK → SZX | Jul 22, 19:15 UTC | Jul 22, 19:25 UTC | 10m |
| 2026-07-22 | CSS7109 | PEK → SZX | Jul 22, 16:35 UTC | Jul 22, 16:55 UTC | 20m |
| 2026-07-21 | CSS7110 | SZX → PEK | Jul 21, 21:40 UTC | Jul 21, 21:55 UTC | 15m |
| 2026-07-20 | CSS6802 | EHU → SZX | Jul 20, 21:00 UTC | Jul 20, 21:25 UTC | 25m |
| 2026-07-16 | CSS6803 | - | Jul 16, 16:55 UTC | Jul 16, 17:05 UTC | 10m |
| 2026-07-15 | CSS6808 | - | Jul 15, 03:05 UTC | Jul 15, 03:20 UTC | 15m |
| 2026-07-14 | CSS6807 | - | Jul 14, 19:45 UTC | Jul 14, 19:55 UTC | 10m |
| 2026-07-10 | CSS6802 | - | Jul 10, 20:50 UTC | Jul 10, 21:10 UTC | 20m |
| 2026-07-10 | CSS3014 | - | Jul 10, 03:15 UTC | Jul 10, 03:25 UTC | 10m |
| 2026-07-09 | CSS6807 | - | Jul 9, 20:05 UTC | Jul 9, 20:15 UTC | 10m |
| 2026-07-09 | CSS6808 | - | Jul 9, 01:10 UTC | Jul 9, 01:30 UTC | 20m |
| 2026-07-07 | CSS6807 | - | Jul 7, 19:45 UTC | Jul 7, 19:55 UTC | 10m |
| 2026-07-07 | CSS6808 | - | Jul 7, 03:10 UTC | Jul 7, 03:20 UTC | 10m |
| 2026-07-04 | CSS6804 | - | Jul 4, 21:25 UTC | Jul 4, 21:40 UTC | 15m |
| 2026-07-04 | CSS6805 | - | Jul 4, 16:40 UTC | Jul 4, 16:50 UTC | 10m |
| 2026-07-04 | CSS6808 | - | Jul 4, 00:55 UTC | Jul 4, 01:15 UTC | 20m |
| 2026-07-03 | CSS6807 | - | Jul 3, 20:00 UTC | Jul 3, 20:10 UTC | 10m |
| 2026-07-03 | CSS6814 | - | Jul 3, 01:05 UTC | Jul 3, 01:15 UTC | 10m |
| 2026-07-02 | CSS6814 | - | Jul 2, 22:20 UTC | Jul 2, 22:40 UTC | 20m |
| 2026-07-02 | CSS6813 | - | Jul 2, 18:35 UTC | Jul 2, 18:45 UTC | 10m |
| 2026-07-02 | CSS6814 | - | Jul 2, 01:05 UTC | Jul 2, 01:25 UTC | 20m |
| 2026-07-01 | CSS6814 | - | Jul 1, 22:30 UTC | Jul 1, 22:45 UTC | 15m |
| 2026-07-01 | CSS6808 | - | Jul 1, 00:30 UTC | Jul 1, 00:55 UTC | 25m |
| 2026-06-30 | CSS6807 | - | Jun 30, 19:50 UTC | Jun 30, 20:00 UTC | 10m |
| 2026-06-29 | CSS6807 | - | Jun 29, 19:49 UTC | Jun 29, 20:00 UTC | 10m |
| 2026-06-26 | CSS6807 | - | Jun 26, 19:55 UTC | Jun 26, 20:04 UTC | 10m |
| 2026-06-24 | CSS6807 | - | Jun 24, 19:49 UTC | Jun 24, 19:59 UTC | 10m |
| 2026-06-23 | CSS6807 | - | Jun 23, 20:10 UTC | Jun 23, 20:19 UTC | 10m |
| 2026-06-23 | CSS6808 | - | Jun 23, 00:30 UTC | Jun 23, 00:54 UTC | 25m |
| 2026-06-22 | CSS6807 | - | Jun 22, 19:40 UTC | Jun 22, 19:49 UTC | 10m |
| 2026-06-21 | CSS6804 | - | Jun 21, 21:10 UTC | Jun 21, 21:24 UTC | 15m |
| 2026-06-21 | CSS6805 | SZX → EHU | Jun 21, 17:05 UTC | Jun 21, 17:20 UTC | 15m |
| 2026-06-20 | CSS7088 | - | Jun 20, 00:29 UTC | Jun 20, 00:39 UTC | 10m |
| 2026-06-04 | CSS6809 | - | Jun 4, 16:40 UTC | Jun 4, 16:50 UTC | 10m |
| 2026-06-03 | CSS6810 | - | Jun 3, 21:20 UTC | Jun 3, 21:35 UTC | 15m |
| 2026-05-18 | CSS3001 | - | May 18, 12:55 UTC | May 18, 13:05 UTC | 10m |
| 2026-05-16 | CSS6806 | EHU → SZX | May 16, 21:00 UTC | May 16, 21:20 UTC | 20m |
| 2026-04-21 | CSS6803 | SZX → EHU | Apr 21, 17:20 UTC | Apr 21, 17:30 UTC | 10m |
| 2026-04-19 | CSS6802 | EHU → SZX | Apr 19, 21:15 UTC | Apr 19, 21:25 UTC | 10m |
| 2026-04-17 | CSS6831 | - | Apr 17, 00:40 UTC | Apr 17, 00:50 UTC | 10m |
| 2026-04-15 | CSS6802 | EHU → SZX | Apr 15, 22:05 UTC | Apr 15, 22:25 UTC | 20m |
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-227F page for operator, model, and routing details .