Although commercial aviation adopted winglets years ago, the US Air Force transport fleet has many aircraft that could benefit from the improved fuel efficiency that they provide.
Installing winglets is one technology being trialed by the USAF, ribs is another (see USAF testing vortex reduction on C-17).
At Eglin Air Force Base in Florida, USA, the USAF’s 413th Flight Test Squadron is testing a modified Lockheed MC-130J fitted with winglets. The crew and test engineers flew the modified aircraft eight times and collected data on possible fuel efficiency improvements and performance with the winglets and an installed lift distribution control system.
April 22, 2016