In 1977, NASA, the U.S. Air Force, and The Boeing Company, headquartered in Chicago, initiated a winglet flight test program at Dryden Flight Research Center. Whitcomb’s Langley team provided the design, and Boeing, under contract with NASA, manufactured a pair of 9-foot-high winglets for the KC-135 test aircraft provided by the Air Force.

Whitcomb was validated: The tests demonstrated a 7-percent increase in lift-drag ratio with a 20-percent decrease in induced drag—directly in line with the Langley engineer’s original findings. Furthermore, the winglets had no adverse impact on the airplane’s handling. The Dryden test program results indicated to the entire aviation industry that winglets were a technology well worth its attention.

The 1970s were an important decade for winglet development for smaller jet aircraft, with manufacturers Learjet and Gulfstream testing and applying the technology. Winglets for large airliners began to appear later; in 1989, Boeing introduced its winglet-enhanced 747-400 aircraft, and in 1990 the winglet-equipped McDonnell Douglas MD-11 began commercial flights following winglet testing by the company under the ACEE program.

In 1999, Aviation Partners Boeing (APB) was formed, a partnership with Seattle-based Aviation Partners Inc. and The Boeing Company. The companies created APB initially to equip Boeing Business Jets, a 737 derivative, with Aviation Partners’ unique take on the NASA-proven winglet technology: Blended Winglets