sensors Mode-S transponder
151D99
ICAO 24-bit transponder address · allocated to Russia
Currently assigned to RA-73113 · BOEING 737-800
- Hex
- 151D99
- Octal
- 05216631
- Decimal
- 1,383,833
- Country
- RU
- Tail
- RA-73113
- Type
- B738
- Flights observed
- 4
- Distinct callsigns
- 2
- Country
- RU
- Last broadcast
- 1d ago
Last known position
Country allocation
The ICAO 24-bit address 151D99 falls within the block assigned to Russia (RU) by ICAO Annex 10, Volume III. Every aircraft registered in Russia 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 2 distinct
| Callsign | Airline | Flights | Last seen |
|---|---|---|---|
| AFL1491 | Aeroflot Russian Airlines | 2 | 2026-05-14 |
| AFL1490 | Aeroflot Russian Airlines | 2 | 2026-05-13 |
Recent flights last 4
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-05-14 | AFL1491 | KJA → SVO | May 14, 15:25 UTC | May 15, 10:10 UTC | 18h 45m |
| 2026-05-14 | AFL1491 | KJA → SVO | May 14, 12:25 UTC | May 15, 10:10 UTC | 21h 45m |
| 2026-05-13 | AFL1490 | SVO → KJA | May 13, 17:55 UTC | May 14, 15:35 UTC | 21h 40m |
| 2026-05-12 | AFL1490 | SVO → KJA | May 12, 12:35 UTC | May 12, 17:30 UTC | 4h 55m |
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 RA-73113 page for operator, model, and routing details .