Editing Wingtip device (section)

=== Early development ===
[[File:D-ALCF (14410530949).jpg|thumb|Winglet of [[McDonnell Douglas MD-11]]F]]
[[Richard T. Whitcomb]], an engineer at [[NASA]]'s [[Langley Research Center]], further developed Hoerner's concept in response to the sharp increase in the cost of fuel after the [[1973 oil crisis]]. With careful aeronautical design he showed that, for a given bending moment, a near-vertical winglet offers a greater drag reduction compared to a horizontal span extension.<ref name="McLean Understanding">{{cite book |last1=McLean |first1=Doug |title=Understanding aerodynamics : arguing from the real physics |date=2013 |publisher=Wiley-Blackwell |location=Chichester |isbn=978-1119967514 |page=422}}</ref> Whitcomb was the first to realize a net benefit in drag reduction by careful design to keep profile drag to a minimum.<ref name="McLean Boeing" />

Whitcomb's designs were flight-tested in 1979–80 by a joint NASA/Air Force team, using a [[KC-135 Stratotanker]] based at the [[Dryden Flight Research Center]].<ref name="nasa_c2r" /> A [[Lockheed L-1011]] and [[McDonnell Douglas DC-10]] were also used for testing, and the latter design was directly implemented by McDonnell Douglas on the derivative [[MD-11]], which was rolled out in 1990.<ref name="nasa_c2r" />

In May 1983, a high school student at [[Bowie High School (Maryland)|Bowie High School in Maryland]] won a grand prize at the 34th [[International Science and Engineering Fair]] in [[Albuquerque, New Mexico]] for the result of his research on wingtip devices to reduce drag.<ref>{{cite news |last1=Wynter |first1=Leon |title=Bowie Youth Sweeps Science 'World Series' |url=https://www.washingtonpost.com/archive/politics/1983/05/18/bowie-youth-sweeps-science-world-series/d620ac97-0aa7-4508-9da3-16c10f5277e4/ |newspaper=[[Washington Post]] |date=May 18, 1983}}</ref>{{importance inline|date=April 2021}} The same month, he filed a U.S. patent for "wingtip airfoils", published in 1986.<ref>patent {{patent|US|4595160}}</ref>{{importance inline|date=April 2021}}