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Old 9th Dec 2006, 12:57
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eckhard
 
Join Date: May 2005
Location: France
Age: 69
Posts: 1,143
Received 4 Likes on 3 Posts
Yes, Kreuger flaps between fuselage and inner engines and 'variable camber leading edge flaps' between the engines and outboard to the tip.

The VCLEFs are unique, as far as I am aware, on commercial aircraft in that they bend as they are deployed. When retracted they are flat (in line with the under side of the leading edge) but as they extend, a clever scissors support mechanism bends them to a more efficient aerodynamic curve. The very tip of each flap is in the form of a 'nose' which unfolds and provides a blunt leading edge to the whole affair.

Disadvantages include:

Wing bleed air de-icing does not work with them extended;

During extension/retraction they are momentarily at right angles to the airflow and therefore increase drag, reduce lift and reduce the manouever margin (watch your bank angle!); and

The flexing material sometimes causes the paint to crack and peel off.

Good luck with your next interview!
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