A Recurring Nightmare: Transonic Wing Drop
March 14, 2011
- Dr. Robert Niewoehner
- United States Naval Academy
- 1010 Torgersen Hall
- 10:00 a.m.
Dr. Niewoehner’s first flight during the F/A-18 E/F’s development exposed a nightmare. Further testing revealed a strong transonic abrupt wing stall (“wing drop”) which nearly caused the technical collapse of the Super Hornet as a program.
Embarrassingly, the wind tunnel develop had provided advance clues, yet clues that no one in government or industry were prepared to properly interpret. Had those clues been seen by engineers of the 1950s, the problem would have been diagnosed long before first flight; the challenge was not new, but forgotten. A two-year effort, flown principally by Dr. Niewoehner, devised an imperfect fix. The airplane was fielded on time, and won laurels in battle, yet two questions remained. “Can we find a better fix?” “Can we avoid being surprised by this again?” A Navy/NASA/Industry effort was
funded by the Joint Strike Fighter office to better understand the phenomenology, including its historical impacts, and then develop diagnostics for mitigating the challenge in future designs. The F-35C now sports spoilers on its outboard wing panels
mitigating the risk of its appearance in that program’s design. This presentation will recount the history, findings, and applications of the study group’s work.