Originally Posted by verticalhold
<snip> to demand the temporary lanes being permanently marked on the map. <snip>
But, vh, (in the cartographers' and Special's defence), if the TEMPORARY lanes were marked on the chart then they would be presumed to be permanent and hence people would ask for them (when they wouldn't be available, albeit for a few days of the year. Bearing in mind that the traffic for Ascot and Epsom is just a fraction of all heli movements through the zone throughout the year).
And, yes, I'm aware that if Heathrow are on 27, the 'unofficial' Burnham/Ascot (ie H11) lane will often be granted if it sounds like you know what you're doing.
And judging by some of the comments above, it seems as if there are pilots who try and navigate through the lanes without reference to the helilanes chart. It's no wonder Special get exasperated at times!