PPRuNe Forums - View Single Post - Short Field Landing Techniques
View Single Post
Old 9th Apr 2006, 13:09
  #28 (permalink)  
Centaurus
 
Join Date: Jun 2000
Location: Australia
Posts: 4,189
Likes: 0
Received 19 Likes on 6 Posts
To John at Tullamarine. Very well put I thought - and dead correct.

A little tip on the effectiveness of aerodynamic braking, induced drag and all the jazz. In another era I read of an over-run accident to a Vampire single seat fighter where the pilot used aerodynamic braking in the early part of his landing run but left the wheel braking too late and ploughed into an adjoining field. As he saw the end of the runway looming he rapidly wound back the sliding cockpit canopy in order (in his own words) "to attain more drag" He had read somewhere that driving with a window open in a car causes drag and also increases fuel burn.

The President of the Court of Inquiry (Wing Commander Spry of Air Clues fame) added his own comments, suggesting that a better way of obtaining drag in the case before him, would be to carefully fold a handkerchief at four corners and hold it outside the open canopy to act as a mini-braking parachute....

While so called aero-dynamic braking may be relatively effective at high speeds it is useless at low speeds. And in all cases wheel braking is best of the lot. The drag caused by aerodynamic braking was primarily responsible for two of the DH Comet airliner over-run accidents where the nosewheel was deliberately lifted off the ground early in the take off run as part of then jet take off technique. As the speed increased so did the drag by V squared. Later, Boeing (?) introduced the take off by numbers technique leaving the nose-wheel on the ground until rotation (VR) speed was attained.
Centaurus is offline