Set 3 Theory PYP Flashcards
Principle of operation & Function of FM - CW Radio Altimeter System?
Principle of operation, during time interval of transmission and receiving signal (t2 – t1), the transmitted frequency and received frequency are mixed, producing the difference in frequency from the Mixer (ft – fr = △f). Difference in frequency is directly proportional to the time interval (△t = t2 – t1) which is proportional to altitude (h).
Function of Radio Altimeter – determines the altitude/height above ground by a radio signal (in the case of bad weather approaches)
What is the function and principle of operation of TCAS?
Purpose: Designed to reduce danger of mid-air collisions between aircraft by monitoring the airspace around the aircraft, independent of air traffic control, and warns pilots of the presence of other aircraft which may present a threat of Mid-Air Collision (MAC).
Operation: Each TCAS equipped aircraft interrogates all other aircraft in a determined range about their position (via 1030 MHz), and all other aircraft reply to interrogation (via 1090 MHz). This interrogation-and-response cycle may occur several times per second, by which the TCAS system builds a three-dimensional map of aircraft in the airspace, incorporating their bearing, altitude and range. Then, by extrapolating current range and altitude difference to anticipated future values, it determines if a potential collision threat exists.
ILS indicator localizer measures difference in ___ between 2 signals in ___ band.
Depth of modulation; VHF
Purpose of ELT?
ELT is used for emergency locating in case of crash sites and survivors.
Advantages of SELCAL
Reduce workload on pilots since they do not need to listen to alot of static and receiver noise from radio. SELCAL also allows pilot to mute the receiver until ATC transmits a group of 2 pulses, and activates an alarm to unmute.
Advantages of SELCAL
Reduce workload on pilots since they do not need to listen to alot of static and receiver noise from radio. SELCAL also allows pilot to mute the receiver until ATC transmits a group of 2 pulses, and activates an alarm to unmute.
Principle of Operation of TSRB in finding angle of approach in azimuth and elevation.
A narrow fan-shaped beam is swept from one side to another at an accurate constant speed, and back again after a time interval.
The Fan swept horizontally provides position line azimuth.
The horizontal oriented fan beam swept up and down gives position line in elevation.
Principle of operation of DME
Principle of Operation - At page 9-8, the video signal from the receiver (which is the IF signal that’s amplified and decoded) is sent to the range computer in the Airborne DME, which measures the elapsed time from interrogation to reception, to solve the range equation (D = v x t). But essentially, it’s the time that elapsed from reception and interrogation to calculate range
Purpose of P2 pulse in Ground to Air ATC interrogation signals
P2 pulse is a reference pulse for Side Lobe Suppression. It is used to determine the if signal is valid, by checking if P2 pulse has amplitude that is 9dB or lower than P1 pulse (Main lobe).
What can share on antenna
VOR and Localizer signals are received by whip antennas.
Glideslope is dipole antenna at the nose
