Ultralight(超轻型的) airplanes are a recent development in aviation that provid

游客2023-11-15  20

问题      Ultralight(超轻型的) airplanes are a recent development in aviation that provide what aviation enthusiasts have long been seeking: an inexpensive airplane that is easy to fly. The ultralight plane was born of the marriage of the hang glider and the go-kart(微型单座赛车) engine around 1974, when John Moody mounted a 12-horsepower go-kart engine on his Icarus Ⅱ hang glider.
     Today’s ultralights are not just hang gliders with engines; they are" air recreation vehicles". Modem ultralight planes use snowmobile(雪地机动车)engines that let them cruise at about 50 miles per hour, climb at about 500 feet per minute, and carry combined payloads of pilot and fuel up to about 200 pounds, which is about equal to an ultralight plane’s weight when empty. More than ten thousand ultralight planes were sold last year at prices ranging from $ 2,800 to $ 7,000. But the main reason for the increasing popularity of these aircraft is not that they are inexpensive, but that they are fun to fly.
    The modern ultralight plane would look very familiar to the earliest pioneers of aviation. Otto Lilienthal made more than 2000 flights in Germany in the 1890’s in what were actually hang gliders. Octave Chanute designed and built many early hang gliders. Augustus Herring, Chanute’s assistam, used these gliders as models for a glider that he built for him self. On this glider, Herring installed a compressed-air motor and flew 267 feet in 1898. The Wright brothers’ Flyer was the grandfather of today’s ultralight plane. The pilot sat right out in the open, just as in modem ultralights, and used con trois that were much the same as those used in today’s machines.
    Though most ultralight planes are used for pleasure flying, some are also used for crop dusting, aerial photography, and even military observation service. The likelihood is that further uses will be found for ultralight planes, but their greatest use will continue to be as air recreational vehicles. [br] The best title for this passage is ______.

选项 A、The Flying Snowmobile
B、The History of Recent Aviation
C、How the Ultralight Plane Flies
D、The Ultralight Plane, a Recent Development

答案 D

解析 根据全文及各段大意,A项太窄;B项太宽;C项也太窄。D项为第一段段首句,一般为主题所在位置。其涵盖适中,故为本题答案。
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