当雷达所检测的目标有起伏时，则对雷达的检测性能（）。

For aircraft equipped with a transponder, crew members should squawk（ ）if they lost radio contact with ground.

Commence means （ ） .

For aircraft equipped with a transponder, crew members should squawk（ ）if hijacked.

Baric altimeter reflects the flight altitude by measuring （ ）.

Standard rate for a turning is （ ） degrees per second.

An aircraft flying IFR should not request a change to VFR unless it is expected that it can continue in （ ） for a reasonable period of time.

What is the best course of action for a pilot to follow when thunderstorms are observed along the route of flight?

Which is the routine weather report?

Circumnavigate means （ ） .

The hotter the climate and the higher the airfield above sea level, the （ ） the runways have to be.