
1) Wing configuration
Found on
https://www.crosswordclues.com/clue/swept-wing

A swept wing is a wing planform favored for high subsonic and supersonic speeds, and is found on almost all jet aircraft in one form or another, as well as some high speed propeller aircraft. Compared with straight wings common to slower aircraft, they have a `swept` wing root to wingtip direction angled beyond (usually aftward) the spanwise axi.....
Found on
http://en.wikipedia.org/wiki/Swept_wing

(from the article `airplane`) Swept wings are angled, usually to the rear and often at an angle of about 35°. Forward swept wings also are used on some research craft.
Found on
http://www.britannica.com/eb/a-z/s/196
No exact match found.