Correct Answer : Phase shifter
Explanation : The ESA has no mechanical moving parts, such as antenna gimbals, potentiometers, rotary joints, or hydraulic/electronic motors. It uses phase shifters to electronically steer the beam.
Correct Answer : Option (C) : 200 nmi
Explanation : The use of airborne weather radar is one method of storm avoidance. A weather radar system can show centers at a distance of up to 200 nmi.
Correct Answer : Option (D) : 9375 MHz
Explanation : The weather radar operates at a frequency of 9375 MHz, corresponding to a wavelength of 3 cm. This small wavelength gets easily reflected from clouds containing high water concentrations.
Correct Answer : Option (B) : 25 dB
Explanation : The signal strength of echoes from storms located at a distance from the aircraft is very low, which requires the transmitter to operate at very high power levels and that the antenna have a gain of more than 25 dB.
