sensors Mode-S transponder
4243E6
ICAO 24-bit transponder address · allocated to United Kingdom
Currently assigned to VQ-BBB · BOEING 737-900
- Hex
- 4243E6
- Octal
- 20441746
- Decimal
- 4,342,758
- Country
- GB
- Tail
- VQ-BBB
- Type
- B739
- Flights observed
- 17
- Distinct callsigns
- 11
- Country
- GB
- Last broadcast
- 7d ago
Last known position
Country allocation
The ICAO 24-bit address 4243E6 falls within the block assigned to United Kingdom (GB) by ICAO Annex 10, Volume III. Every aircraft registered in United Kingdom 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 11 distinct
| Callsign | Airline | Flights | Last seen |
|---|---|---|---|
| SMR222 | Somon Air | 3 | 2026-05-01 |
| SMR214 | Somon Air | 2 | 2026-05-18 |
| SMR110 | Somon Air | 2 | 2026-05-21 |
| SMR109 | Somon Air | 2 | 2026-05-21 |
| SMR103 | Somon Air | 2 | 2026-05-15 |
| SMR8183 | - | 1 | 2026-05-02 |
| SMR3110 | - | 1 | 2026-05-25 |
| SMR3109 | - | 1 | 2026-05-25 |
| SMR213 | Somon Air | 1 | 2026-05-17 |
| SMR106 | Somon Air | 1 | 2026-04-16 |
| SMR105 | Somon Air | 1 | 2026-04-16 |
Recent flights last 17
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-05-25 | SMR3110 | - | May 25, 22:15 UTC | May 26, 12:10 UTC | 13h 55m |
| 2026-05-25 | SMR3109 | - | May 25, 19:10 UTC | May 25, 20:09 UTC | 1h 0m |
| 2026-05-21 | SMR110 | DEL → DYU | May 21, 10:50 UTC | May 21, 11:30 UTC | 40m |
| 2026-05-21 | SMR109 | DYU → DEL | May 21, 08:05 UTC | May 21, 08:50 UTC | 45m |
| 2026-05-18 | SMR214 | KJA → DYU | May 18, 06:50 UTC | May 18, 11:10 UTC | 4h 20m |
| 2026-05-17 | SMR213 | DYU → KJA | May 17, 10:00 UTC | May 18, 07:25 UTC | 21h 25m |
| 2026-05-15 | SMR103 | DYU → IST | May 15, 03:40 UTC | May 15, 10:35 UTC | 6h 55m |
| 2026-05-11 | SMR214 | KJA → DYU | May 11, 06:15 UTC | May 11, 11:35 UTC | 5h 20m |
| 2026-05-02 | SMR8183 | - | May 2, 07:55 UTC | May 2, 14:20 UTC | 6h 25m |
| 2026-05-01 | SMR222 | OVB → DYU | May 1, 12:15 UTC | May 2, 08:20 UTC | 20h 5m |
| 2026-05-01 | SMR222 | OVB → DYU | May 1, 09:35 UTC | May 2, 08:20 UTC | 22h 45m |
| 2026-05-01 | SMR222 | OVB → DYU | May 1, 09:15 UTC | May 1, 12:40 UTC | 3h 25m |
| 2026-04-27 | SMR110 | DEL → DYU | Apr 27, 11:55 UTC | Apr 27, 12:25 UTC | 30m |
| 2026-04-26 | SMR109 | DYU → DEL | Apr 26, 16:25 UTC | Apr 27, 10:25 UTC | 18h 0m |
| 2026-04-17 | SMR103 | DYU → IST | Apr 17, 03:35 UTC | Apr 17, 05:05 UTC | 1h 31m |
| 2026-04-16 | SMR106 | DXB → DYU | Apr 16, 04:29 UTC | Apr 16, 05:05 UTC | 35m |
| 2026-04-16 | SMR105 | DYU → DXB | Apr 16, 01:35 UTC | Apr 16, 02:09 UTC | 35m |
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 VQ-BBB page for operator, model, and routing details .