Oversteer, what do you want the data for?
There is a small army of people who prepare, on a voluntary basis, airspace definition files for use with UK gliding moving map software. There are several versions of the files, in different formats, to suit different software purveyors.
These people do it because there is no authoritative source for some of the data from the CAA or anywhere else.
(I am not myself an expert on this, just a user, so what follows is my interpretation of what I have been told.)
Just one example – an airway is defined in the UKAIP as a 10 nm wide chunk whose centreline is defined, terminating where it intersects the boundary of an LTMA segment. The boundary is defined as a series of straight lines joining specified points. The airway end points can be calculated from these two sets of data. Each person doing this has their own spreadsheet or equivalent for doing the calculations.
Some more complicated points require an interpretation of the official data, and two different people might make quite reasonable different interpretations in the absence of anything official.
I use one of these, and so have a file that contains the interpreted data as a text file. It must be somebody’s copyright, and comes with disclaimers, as one might expect.
I believe that the community of these people communicate with each other, at least to some extent, and do some cross checks so that most if not all errors are eliminated.
I don’t know how companies do it who sell their data, or how robust their process is.
Chris N.
Last edited by chrisN; 3rd Aug 2009 at 10:50.