NASA used the Boeing KC-135 in the early 1980s to pioneer the design of the winglets that are now ubiquitous on commercial airliners and business jets.
Now, in a full-circle-Oprah moment, winglet technology may be coming back to the KC-135, only this time to benefit the refueling fleet itself.
Upon the request of the Air Force Research Laboratory and Air Mobility Command, the Air Force Academy published a study last month with new findings showing that adding winglets could reduce KC-135R fuel burn by 8%. They may have saved themselves some trouble by simply referring to NASA's original study, which predicted a 7% benefit.
The US Air Force spends $1 billion a year to pay for the gas consumed by KC-135s and KC-10s, according to this Rand web site. An 8% fuel savings extrapolates to $80 million a year. But the question remains how to pay for it. There is apparently some level of Congressional interest in the project, as Congress ordered the USAF to commission Rand's analysts to publish another study about KC-135R winglets.