送交者: foresight 于 2010-12-14, 12:19:12:

回答: helicopter is very difficult, single engine plane is easy. 由 steven 于 2010-12-14, 11:36:57:

• comparing to typical propeller aircrafts, yes. (无内容) - steven (0 bytes) 2010-12-14, 12:34:48 (525644)

加跟贴