相关题目
The （ ） signal by radiotelephony is MAYDAY and by radiotelegraphy SOS.
（ ） a windshear near the ground on final.
In an aircraft，the ADF permits a pilot to （ ） continuous bearings automatically on any ground station operating on a frequency usable by the airborne equipment.
Automatic direction finding (ADF) is an airborne （ ） the ground Direction Finding equipment.
With too much clutter, a controller （ ） see the aircraft.
The accommodation and reception of the flight crew undertaking the special flight is the responsibility of （ ） . The local airport or aeronautical station may also have authorization to fulfill this task.
Based on the circumstances of a special flight, the airlines can send （ ） to fly with the crew to handle such work as flight navigation, delivery and coordination.
When the word radar is used alone, it usually includes （ ） .
When special flight is in operation, （ ） should have its flight status in hand and monitor it all through the flight.
At night or during poor visibility by day, lights are （ ） . For lights to be effective, they must be of adequate intensity.
