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AirNav RadarBox and RadarBox24.com => AirNav RadarBox and RadarBox24.com Discussion => Topic started by: wojteksz on August 28, 2010, 09:09:30 AM

Title: planes appear to land not on the airport ?
Post by: wojteksz on August 28, 2010, 09:09:30 AM
Hello to everyone,
I am new to airnav and trying to cover the gap in the center of Poland ;)
temporarily working with the default antenna not perfectly located but covering the planes landing on Warsaw Okecie airport EPWA at least down to some FL100. Unfortunately it seems that the planes align with the runway located a few mile west from the original airport location ( i see them flying perpendicular to the direction of active runway, descending and slowing down - so must be loading!). Yet the position is definitely wrong  - i have checked the outline of the airport against Google Earth and confirmed that the outline is correct.
How can i compensate this?
Title: Re: planes appear to land not on the airport ?
Post by: DaveReid on August 28, 2010, 09:42:01 AM
How can i compensate this?

You can't.

Some aircraft, for example many 767s and older 737s, send position data that's based on inertial navigation systems, which are subject to drift, rather than GPS, which isn't.
Title: Re: planes appear to land not on the airport ?
Post by: wojteksz on August 28, 2010, 12:41:08 PM
Dave,
thanks, seems i have to learn to live with it ;)
i have also noticed that sometimes the plane track gets somehow backed by some 1..2 miles. What could be the reason?
Title: Re: planes appear to land not on the airport ?
Post by: Runway 31 on August 28, 2010, 12:58:35 PM
wojteksz, what version of the softare are you using?

Alan
Title: Re: planes appear to land not on the airport ?
Post by: DaveReid on August 28, 2010, 03:00:51 PM
i have also noticed that sometimes the plane track gets somehow backed by some 1..2 miles. What could be the reason?

Same reason, INS drift isn't necessarily lateral, it can just as easily have a component along track, in either direction.
Title: Re: planes appear to land not on the airport ?
Post by: wojteksz on August 28, 2010, 04:13:09 PM
Alan
i am using radarbox 4.03 with the standard antenna installed outdoor (hope it will survive out there untill a proper outside antenna will arrive ;))
Wojtek
Title: Re: planes appear to land not on the airport ?
Post by: AirNav Support on August 28, 2010, 04:39:33 PM
Sir,

We seriously advise not to use your antenna outdoors for a long period of time. It should only be used outside as mobile sites (visiting the airport etc..)
The antenna is not designed to withstand the elements.

Also please read

http://www.airnavsystems.com/forum/index.php?topic=2759.0
Title: Re: planes appear to land not on the airport ?
Post by: wojteksz on August 28, 2010, 05:04:25 PM
Support
i know, i know...
my newly ordered 1090 WiMo outside antenna set is on its way ;)
i just could not wait to see the planes flying so took the antenna from the window and installed (?) it on the nearest roof edge. Somewhat not perfect location but gives in best direction over 120mi range.
Title: Re: planes appear to land not on the airport ?
Post by: wojteksz on September 04, 2010, 06:58:17 PM
got the new antenna installed and running temporarliy on the laptop - better round reception much more planes observed ;)