# Avionics Mcqs

Q:

What is the minimum safe approach distance for a radar system operating in excess of 5kWhr?

 A) 100ft B) 10ft C) 17ft D) 4ft

Explanation: With radar system operating in excess of 5kW output, the minimum safe approach distance to weather radar is about 4ft.

44
Q:

A power of 5 kW to 50 kW is required even when using narrow beams.

 A) True B) False

Explanation: Even with narrow beamwidth antennas, the radar transmitter requires from 5kW to 50kW of output power. When coupled with an antenna of 25 dB, this combination can result in an effective power more than a million watts.

64
Q:

What is the gain required by a weather radar antenna?

 A) 65 dB B) 50 dB C) 25 dB D) 5 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.

43
Q:

What is the frequency of operation of weather radar?

 A) 1000 MHz B) 500 kHz C) 9375 MHz D) 548 kHz

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.

37
Q:

What is the range of typical weather radar?

 A) 500 nmi B) 50 nmi C) 5 nmi D) 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.

46
Q:

Whisper shout is used to avoid garble in TCAS.

 A) True B) False

Explanation: TCAS uses two different methods to avoid garbling. One is whisper shout and the other is using directional interrogations.

45
Q:

TCAS I provide proximity warning only.

 A) True B) False

Explanation: TCAS I provide only proximity warning and aids the pilot in visual identification of potential threat aircraft.

47
Q:

What is the surveillance range of a general TCAS system?

 A) 30 sec B) 20 min C) 2 min D) 4 min