[OSM-talk] Need help with mathematics for runways

[Martin Spott]

Hi,

OJW wrote:

> The runway "position" is a lat/long of the spot where they touch down, where 
> the zebra-crossing stripes and runway number are.  There is a "dead 
> zone" (unmarked tarmac) behind that line, then there's the runway length in 
> front of that line, then an overrun zone at the opposite end of the runway.  
> Some data files give you the lengths of those extra zones, which is useful if 
> you want to draw the tarmac area as well as just the official runway area.

Just to avoid confision on this topic: The lat/lon given for a runway
in the X-Plane/FlightGear v8.10 database as well as at least on the
printed Jeppesen sheets marks the center of the runway. As you can read
on:

  http://www.x-plane.org/home/robinp/Apt810.htm

....  the mentioned database already contains the stopway length for
those airports where someone already provided the respective numbers.
The v8.50 format, currently sort of still in development, has a
different notation than that of v8.10 as it carries a distinct
definition of both runway directions, together with threshold locations
instead of the runway center.


> p.s. just a note: if you can, try to keep as much meta-information as possible 
> from the source files (e.g. heights at each end, which airport code each 
> runway is associated with, frequencies for each transmitter, that sort of 
> thing) because it means that a DAFIF-style file can then be recreated from 
> OSM data later. (and as other people have noted, this information could be 
> quite a valuable "product" for OSM to offer later)

What are you aiming at ?

Cheers,
	Martin.
-- 
 Unix _IS_ user friendly - it's just selective about who its friends are !
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