飞行员们常常将飞机的自动驾驶系统视为一个难以理解的黑匣子。

Pilots often consider the plane's autopilot system as a ___black box they don't fully understand.

航空公司正在努力寻找失事飞机的黑匣子。

The airline is working hard to locate the ___black box of the crashed plane.