Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

4851B1

ICAO 24-bit transponder address · allocated to Netherlands

Currently assigned to PH-BHF · BOEING 787-9 Dreamliner

Hex
4851B1
Octal
22050661
Decimal
4,739,505
Country
NL
Tail
PH-BHF
Type
B789
Broadcasting now · callsign KLM862 · 37,300 ft
Flights observed
198
Distinct callsigns
20
Country
NL
Last broadcast
6h ago

Current position

4851B1 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4851B1 falls within the block assigned to Netherlands (NL) by ICAO Annex 10, Volume III. Every aircraft registered in Netherlands 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
KLM809 - 17 2026-07-12
KLM751 - 17 2026-07-09
KLM810 - 16 2026-07-12
KLM897 - 12 2026-07-10
KLM896 - 10 2026-07-01
KLM895 - 9 2026-06-30
KLM888 - 8 2026-06-19
KLM856 KLM Royal Dutch Airlines 8 2026-06-07
KLM855 KLM Royal Dutch Airlines 8 2026-06-07
KLM898 - 7 2026-07-11
KLM887 - 7 2026-06-19
KLM808 KLM Royal Dutch Airlines 6 2026-05-14
KLM807 KLM Royal Dutch Airlines 6 2026-05-14
KLM867 - 5 2026-07-06
KLM755 KLM Royal Dutch Airlines 5 2026-05-25
KLM868 - 4 2026-07-07
KLM640 - 4 2026-06-20
KLM639 - 4 2026-06-20
KLM296 - 4 2026-06-24
KLM225 - 4 2026-06-24

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 KLM862 - Jul 14, 03:25 UTCJul 14, 09:30 UTC6h 5m
2026-07-13 KLM861 AMS → NRT Jul 13, 12:20 UTCJul 14, 00:45 UTC12h 25m
2026-07-12 KLM810 - Jul 12, 21:20 UTCJul 13, 06:30 UTC9h 10m
2026-07-12 KLM810 - Jul 12, 18:30 UTCJul 12, 18:45 UTC15m
2026-07-12 KLM810 - Jul 12, 12:50 UTCJul 12, 14:35 UTC1h 45m
2026-07-12 KLM809 - Jul 12, 10:45 UTCJul 12, 11:01 UTC15m
2026-07-12 KLM809 - Jul 12, 09:25 UTCJul 12, 10:15 UTC50m
2026-07-12 KLM809 - Jul 12, 06:50 UTCJul 12, 07:20 UTC30m
2026-07-11 KLM809 - Jul 11, 19:45 UTCJul 12, 04:25 UTC8h 40m
2026-07-11 KLM898 - Jul 11, 14:40 UTCJul 11, 14:50 UTC10m
2026-07-11 KLM898 - Jul 11, 10:05 UTCJul 11, 14:35 UTC4h 30m
2026-07-10 KLM897 - Jul 10, 23:55 UTCJul 11, 00:15 UTC20m
2026-07-10 KLM897 - Jul 10, 14:30 UTCJul 10, 16:55 UTC2h 25m
2026-07-09 KLM751 - Jul 9, 16:50 UTCJul 10, 11:00 UTC18h 10m
2026-07-09 KLM751 - Jul 9, 10:20 UTCJul 10, 10:15 UTC23h 55m
2026-07-09 KLM751 - Jul 9, 09:05 UTCJul 10, 02:35 UTC17h 30m
2026-07-07 KLM868 - Jul 7, 03:20 UTCJul 7, 17:00 UTC13h 40m
2026-07-06 KLM867 AMS → KIX Jul 6, 13:15 UTCJul 7, 01:05 UTC11h 50m
2026-07-05 KLM250 - Jul 5, 20:20 UTCJul 6, 03:40 UTC7h 20m
2026-07-05 KLM655 AMS → MSP Jul 5, 09:35 UTCJul 5, 17:20 UTC7h 45m
2026-07-04 KLM898 - Jul 4, 11:00 UTCJul 4, 15:30 UTC4h 30m
2026-07-04 KLM897 - Jul 4, 01:00 UTCJul 4, 01:20 UTC20m
2026-07-03 KLM897 - Jul 3, 15:40 UTCJul 3, 19:25 UTC3h 45m
2026-07-02 KLM810 - Jul 2, 16:25 UTCJul 3, 04:40 UTC12h 15m
2026-07-02 KLM810 - Jul 2, 12:55 UTCJul 2, 14:35 UTC1h 40m
2026-07-02 KLM809 - Jul 2, 09:40 UTCJul 2, 11:15 UTC1h 35m
2026-07-01 KLM809 - Jul 1, 20:25 UTCJul 2, 07:50 UTC11h 25m
2026-07-01 KLM896 - Jul 1, 05:55 UTCJul 1, 17:15 UTC11h 20m
2026-06-30 KLM896 - Jun 30, 16:25 UTCJul 1, 16:15 UTC23h 50m
2026-06-30 KLM895 - Jun 30, 14:20 UTCJul 1, 14:05 UTC23h 45m
2026-06-30 KLM895 - Jun 30, 13:40 UTCJul 1, 06:20 UTC16h 40m
2026-06-29 KLM166 AUS → AMS Jun 29, 23:19 UTCJun 30, 08:20 UTC9h 0m
2026-06-29 KLM115 AMS → AUS Jun 29, 11:10 UTCJun 29, 20:54 UTC9h 45m
2026-06-28 KLM862 - Jun 28, 03:25 UTCJun 28, 16:49 UTC13h 25m
2026-06-27 KLM861 AMS → NRT Jun 27, 12:19 UTCJun 28, 00:39 UTC12h 20m
2026-06-26 KLM868 - Jun 26, 03:10 UTCJun 26, 16:54 UTC13h 45m
2026-06-25 KLM867 AMS → KIX Jun 25, 12:54 UTCJun 26, 00:55 UTC12h 0m
2026-06-24 KLM296 IAD → AMS Jun 24, 22:35 UTCJun 25, 05:09 UTC6h 35m
2026-06-24 KLM225 AMS → IAD Jun 24, 11:45 UTCJun 24, 19:34 UTC7h 50m
2026-06-24 KLM644 JFK → AMS Jun 24, 02:15 UTCJun 24, 08:30 UTC6h 15m
2026-06-23 KLM643 - Jun 23, 15:44 UTCJun 23, 23:14 UTC7h 30m
2026-06-23 KLM686 - Jun 23, 02:45 UTCJun 23, 12:29 UTC9h 45m
2026-06-22 KLM685 - Jun 22, 12:54 UTCJun 22, 23:55 UTC11h 0m
2026-06-20 KLM640 - Jun 20, 21:00 UTCJun 21, 06:55 UTC9h 55m
2026-06-20 KLM639 AMS → SAN Jun 20, 07:59 UTCJun 20, 18:29 UTC10h 30m
2026-06-19 KLM888 - Jun 19, 19:45 UTCJun 20, 03:34 UTC7h 50m
2026-06-19 KLM888 - Jun 19, 14:29 UTCJun 19, 14:49 UTC20m
2026-06-19 KLM887 - Jun 19, 06:44 UTCJun 19, 07:14 UTC30m
2026-06-18 KLM887 - Jun 18, 20:05 UTCJun 19, 00:00 UTC3h 55m
2026-06-18 KLM862 - Jun 18, 03:25 UTCJun 18, 16:40 UTC13h 15m

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 PH-BHF page for operator, model, and routing details .

Mode-S 4851B1 frequently asked

What is Mode-S code 4851B1?
4851B1 is an ICAO 24-bit transponder address. Allocated to Netherlands. Assigned to PH-BHF.
Where is Mode-S 4851B1 registered?
Mode-S code 4851B1 is allocated to Netherlands (NL). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4851B1 broadcasting right now?
Yes. Mode-S 4851B1 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4851B1, octal 22050661, decimal 4,739,505.
What flights does 4851B1 operate?
Mode-S 4851B1 has broadcast 20 distinct callsigns, including KLM809, KLM751, KLM810, KLM897, KLM896.