PPRuNe Forums - View Single Post - BUZZ and Astaeus at LBA
View Single Post
Old 18th Nov 2002, 06:53
  #9 (permalink)  
14 loop
 
Join Date: Nov 2002
Location: SE of Compton
Posts: 148
Likes: 0
Received 0 Likes on 0 Posts
It isn't necessarily a case of landing distance that is the problem with autolands on 32 but the topography of the runway. Due to the length of the displaced threshold (which was increased when the old '33' was extended to comply with more stringent 'undershoot' regulations) the touchdown zone coincides with the hump where the runway drops away. I have some video footage of a Britannia 757 doing a practice Cat III at LBA which in the flare stage floats along the runway and finally makes with the ground at the bottom of the slope almost halfway down the concrete.

One solution to this problem would be to get rid of the displaced threshold, since that part of the concrete is almost flat, aircraft touching down on this would have no 'floating' problems, additionally this would add some metres to the LDA. To get rid of the displaced threshold the undershoot for 32 would need landfilling to bring it level with the runway - it was done in the mid eighties on the same scale to provide increased apron space, I dont believe it would be massively expensive, particularly if it meant LBA lost its reputation for diverts. Additionally if this work meant some form of parallel taxiway being built form say D1 to the threshold then all the better!
14 loop is offline