Originally Posted by
Mike Cross
Chances are any graphical display software would pick up the locations and draw a pentagon with them at its vertices where the correct plot would have been 15nm radius arcs round each of the points, joined by tangents.
Evening Mike. Same territory, different forum.
I'd argue that, at the very least, a representation of individual points within the E-line can quickly show gross errors in the source data, when the points described in the free-form E-line don't correspond to the bounds formally described in the Q-line.
This situation has a pertinent implication - if the Q-line bounds have been incorrectly stated, then the AIS Narrow Route Brief stands a good chance of not reporting relevant NOTAMs along a specified route.
You'll not doubt recall a bout of Red Arrows transit NOTAMs from last summer which suffered from this, as well as this one:
J7951/09
(The large circle is Q-line bounding area, the smaller circles are the stated RA(T) areas - a Narrow Route Brief from, for example, Cumbernauld to Oban wouldn't have reported this TR(A) at all).
Regardless of how much the AIXM format - if/when it finally arrives (and I do have experience of large projects which intend to unite the world via XML) - will formalise the visualisation of airspace data, unless more rigour is put into the source data, then we won't be much further forwards.
Personally, my motivation for exploring alternative representations of NOTAM data is purely selfish - I've been either in the box, at the hold, or standing on the ground at too many aerobatic competitions as some poor soul, in happy ignorance, sails blithely through without a care in the world - generally spamcans, but the last big one I remember was working for HMG - which prompted me to start thinking of better ways to get the pertinent details into the hands of the people who really should have done a more thorough AIS brief, but didn't - Google Maps, mobile phone handsets, Twitter, finger-puppets; I'll try anything.
The truth is the NOTAM channel is overloaded - there are gems of vital information in there, often swamped by the nasal-twang of minor officialdom attempting to justify an existence, and Squadron Leader Blunty hoping that generating the biggest NOTAM in the book will reflect well on his next appraisal.
If we really want recreational GA to stop bonging TR(A)s, the Reds, aerobatics, displays in general and popup Class A protecting Winky Brown, then the people who are tasked with this need to stop thinking like ATC geeks, and start thinking like advertising geeks.
Edited: Interestingly, my reference to T-witter above was autodonked to PPrune....