Plane out-off Rail Way

[f6gsg]

Hi,

here the screen shot of a plane landing out off the rail way !!!!



of course, it's wrong, but i have some times (2 or 3 by week) some planes
completely moved.

it's not a software problem, because some friends have the
same problem with the sbs-1.

The gap is too important for being a problem of precision of the GPS.
it's often the SAME PLANE (i must verify).

is somebody have this kind of gap ?
and what is the explication (security ?)

I am sad has to believe has a problem of measure

At the same time that would be a lot of credit note on the map a scale of
distance measure (it's not very usefull to estimate the distance)

Patrick / F6GSG

[AirNav Support]

Hi Patrick,

This not an issue with RadarBox or a security measure.

Most aircraft (95%+) which use ADS-B use data from there GPS systems to send out position data. However some older aircraft use there INS systems which are accurate at first but tend to drift on flights and can be up to 3miles from position on landing. This is to do with the transponder setup on aircraft.

Sooner or later all aircraft using ADS-B will used there GPS systems. We haven't seen A320s doing this as its mainly older 737s and 767s which have this. So it may be a faulty GPS on that aircraft and hence they are using INS.

Hope that helps.

[f6gsg]

Hi AirNav,

it's a very good explication, but i'm also surprise to observe that gap
on a A320 !!!!

I am making a list of these planes with GAP.

Thanks,
Patrick / F6GSG

[davis]

I noticed the same problem in Alghero with one A 320 of AIRONE..    Always 3 Nm west of ranwai  . Alwaiys some plane.
 ciao Gianni/ IS0YGB

[ChrisGR]

Here is a good explanation for this question.

http://www.airnavsystems.com/forum/index.php?topic=308.0

Regards
Chris