Aircraft Type Info

[smithgd]

Hi

Can someone tell me where the Aircraft Type (eg B777) data comes from, is it broadcast from the aircraft or via a database linked to the ICAO address?

cheers
smithgd

[RodBearden]

Hi smithgd and welcome to the forum.

The Aircraft type short code isn't broadcast by the aircraft - it is looked up in the Aircraft table in Navdata.db3, derived from the Mode-S code. If the code is not present it is populated from the AirNav server. The AirNav server gets this information from the Gatwick Aviation Society database.

Hope that helps.

Rod

[Allocator]

Hi

Can someone tell me where the Aircraft Type (eg B777) data comes from, is it broadcast from the aircraft or via a database linked to the ICAO address?

cheers
smithgd

The aircraft type is not broadcast by the aircraft, so RadarBox uses its NavData.db3 internal database to match up the received Hex code to the type if the aircraft is in the database.  RB autopopulates the NavData.db3 database from a number of on-line sources.

See the following volunteer maintained databases:

http://www.airframes.org/

http://www.gatwickaviationsociety.org.uk/modeslookup.asp

and this professional database:

http://www.caa.co.uk/application.aspx?catid=60&pagetype=65&appid=1

The problem is that there isn't one database to cover all the aircraft in the world - or rather there isn't a database that is 100% correct as this is an almost impossible task - especially if you want the information for free.

[smithgd]

Thanks for the speedy replies!

So if the aircraft ICAO code isn't in any of the databases nothing is displayed on RB?

Also, is there a list of the messages/info that it receives from the aircraft?

Cheers
smithgd

[Allocator]

Thanks for the speedy replies!

So if the aircraft ICAO code isn't in any of the databases nothing is displayed on RB?

Also, is there a list of the messages/info that it receives from the aircraft?

Cheers
smithgd

If there isn't a record for that aircraft in the database, then you will see:

Hex Code
National Flag (as this is based on the Hex Code)
Flight ID (If it has been set by the crew)
Airline (If there is a valid Flight ID)
Route (If the Flight ID matches a route in the database)
Altitude
Squawk

Plus other info such as position info if the aircraft is transmitting it.  If the aircraft is giving position, it will show on the RB map.

See the picture below - you will see that 2 of these aircraft are not in the database, so the Registration, type and silhouette are missing.

Not sure what you mean by the list of messages received from the aircraft - ACARS maybe?  There is a optional add-on program for adding the ACARS information into the RB interface, but it's fairly basic and I don't tend to use it much.

[smithgd]

From my limited understanding of how mode s works there are various messages sent from the aircraft and they have labels such as "DF17". In this case DF17 is the ADS-B Extended Squitter message but there are others such as DF11 which is an Acquisition Squitter.

I was wondering if there is a list of the DF messages the RB decodes?

cheers
smithgd

[Jeremy]

What is a 'squitter'?
J.

[smithgd]

Think of it as a broadcast message, the transponder doesn't need an interrogation pulse first before it sends out the message.

smithgd

[Aerotower]

http://www.icao.int/anb/ais/8643/MnfctrerList.cfm

[smithgd]

Thanks Steve, how do you know you have received the different DFs, is this displayed on RB somewhere?

Do you know of any "official" document that lists the contents of each DF?

Cheers
smithgd

[smithgd]

A useful doc that, thanks.

cheers
smithgd

[DaveReid]

From my limited understanding of how mode s works there are various messages sent from the aircraft and they have labels such as "DF17". In this case DF17 is the ADS-B Extended Squitter message but there are others such as DF11 which is an Acquisition Squitter.

I was wondering if there is a list of the DF messages the RB decodes?

Both RadarBox and SBS decode the following DFs, although only the SBS has a third-party driver available that will allow you to inspect the contents:

DF4 - Surveillance Altitude
DF5 - Surveillance ID (squawk)
DF11 - All-Call Reply/TCAS Acquisition Squitter
DF17 - Extended Squitter (aka "ADS-B Squitter")
DF20  - Surveillance Altitude/Ground-Initiated Comm-B
DF21  - Surveillance ID (squawk)/Ground-Initiated Comm-B

DF20 & DF21 are used in Europe for ELS/EHS DAPs;  I'm not sure what use, if any, is made of them elsewhere

Not all fields from all of these DFs are displayed.

A "Squitter" simply means a Mode S transmission from an aircraft that isn't in response to a ground station interrogation.

[smithgd]

Thanks Dave