We were both Trustees for Embry Riddle Aeronautical University, which Al strongly supported, and he was a true advocate for Business Aviation as the National Business Aviation Association launched its No Plane, No Gain program in the 1990s.

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Chuck Eastlake, a professor of aerospace engineering at Embry-Riddle Aeronautical University in Florida, said the technology for the reinforcements seems to be relatively basic.

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"More than 28, 000 flights take off each day in the United States, so if you look at the statistics, they're pretty small in relation to the big picture, " said Kees Rietsema, department chair of business administration at Embry-Riddle Aeronautical University.

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Friends who have known each other for decades, or siblings who get along well and are comfortable spending long periods of time with one another, would also be suitable for this sort of situation, said Jason Kring, assistant professor at Embry-Riddle Aeronautical University, who is not involved with the mission.

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