PPRuNe Forums - View Single Post - EK407 Tailstrike @ ML
View Single Post
Old 27th Mar 2009, 07:02
  #318 (permalink)  
A37575
 
Join Date: Apr 2005
Location: Australia
Posts: 1,414
Likes: 0
Received 0 Likes on 0 Posts
The speed trend arrow is extremely useful in determining airspeed acceleration, but provides no direct information as to how much ground you have covered doing so (correct me if I am wrong please) the time/distance check is the only way of ensuring that..
Many decades ago I watched a USAF Douglas B-66 Destroyer (Twin jet engine all weather day/night reconnaissance aircraft) line up and commence take off from Townsville runway 02. It made lots of noise. In those days distance to run markers were set in the flight strip and lit at night. When two thirds down the runway the pilot aborted and was extremely fortunate to stop in the over-run even though the runway then was 8000 ft long. The brakes overheated.

An hour or so later the pilot had another go at getting off and this time was successful. We were later told by ATC that the B-66 had aborted because it had not reached a certain speed by a certain distance down the runway. Yet when the pilot did the second take off the wind and OAT were same as before.

From that, we got the impression that the speed versus distance abort policy was primitive at its best, and a risk laden way of determining whether to stop or go. Certainly no way would you try that sort of approximation in a modern jet transport.
A37575 is offline