现代飞机采用全动平尾的主要目的是（）。

Which of the following does not go with all the others?

Which word does not go with all the others?

Which of the following is a primary control system?

Which of the following is an assistant control system?

Which of the following is not part of empennage?

Which word does not go with all the others?

Which word does not go with all the others?

Which word does not go with all the others?

Which word does not go with all the others?

The five major component parts of an airplane are （ ） ．