Altitude Adjustment

摘要

"WE WILL NOT HAVE TO STOP AIR TRAVEL, BUT we will have to plan for it more carefully," President Nixon told the nation in November 1973. Schedules would be reduced, loads increased, and the use of fuel for aviation cut by 15 percent. Then, as now, we faced a crisis over energy. Nixon's speech followed the OPEC oil shock, but concerns about the climate were already growing. (Scientists would begin to reach consensus on the basic facts of global warming by decade's end.) So an urgent problem came to Richard Whit-comb, a decorated NASA engineer at Lang-ley Research Center in Virginia: Might there be some cheap and easy way to make flying more efficient? In 1974, Whitcomb started playing with an old idea—that you could gain energy efficiency just by bending up the tips of airplane wings until they were almost vertical. After modeling the idea and testing it in wind tunnels, Whitcomb estimated that the "wing-lets" he'd designed could reduce the use of fuel by 6 to 9 percent. Real-world trials of a Boeing 707 confirmed the lab's success.