Testing
In initial testing there were significant problems with the porous materials and surface slots getting plugged with debris, bugs, even rain. In certain conditions, ice crystals would form due to the rapid cooling of air over those laminar surfaces abruptly disrupting laminar flow, causing rapid melting and rapid transition back to turbulent flow. Maximum achievement of 95 percent laminar flow over those areas was desired. However, the design effort was canceled due to the plugging problems.
Nevertheless, pioneering data was obtained in the X-21 flight program, including the effects of surface irregularities, boundary-layer turbulence induced by three-dimensional span-wise flow effects in the boundary layer (referred to as span-wise contamination) and degrading environmental effects such as ice crystals in the atmosphere.
Read more about this topic: Northrop X-21
Famous quotes containing the word testing:
“Traditional scientific method has always been at the very best 20-20 hindsight. It’s good for seeing where you’ve been. It’s good for testing the truth of what you think you know, but it can’t tell you where you ought to go.”
—Robert M. Pirsig (b. 1928)
“Is this testing whether I’m a replicant or a lesbian, Mr. Deckard?”
—David Webb Peoples, U.S. screenwriter, and Ridley Scott. Rachel, Blade Runner, being tested to determine if she is human or machine (1982)
“Today so much rebellion is aimless and demoralizing precisely because children have no values to challenge. Teenage rebellion is a testing process in which young people try out various values in order to make them their own. But during those years of trial, error, embarrassment, a child needs family standards to fall back on, reliable habits of thought and feeling that provide security and protection.”
—Neil Kurshan (20th century)