InterviewSolution
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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 101. |
What error will a 10°C error in temperature shown in true airspeed?(a) 10 Knots(b) 20 Knots(c) 0.2 Knots(d) Greater than 1 Knot |
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Answer» The correct option is (d) Greater than 1 Knot To explain: A 10°C error in the temperature will result in a true airspeed greater than 1 knot at a typical transport aircraft flight conditions. |
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| 102. |
What is the takeoff clearance height for a military aircraft?(a) 50ft(b) 35ft(c) 20ft(d) 100ft |
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Answer» Right answer is (a) 50ft To elaborate: The height that the aircraft must cover during the airborne distance is different for different aircraft depending upon their usage. The height of the obstacle is generally specified to be 50ft for military aircraft and 35ft for commercial aircraft. |
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| 103. |
The angle between the relative wind and the longitudinal datum line on the fuselage is called as?(a) Flight path angle(b) Glide angle(c) Relative angle(d) Angle of attack |
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Answer» The correct choice is (d) Angle of attack The best I can explain: Angle of attack is the angle, in the normally vertical plane of symmetry of the aircraft, at which the relative wind meets an arbitrary longitudinal datum line on the fuselage. Angle of attack, is important as it corresponds to the amount of lift produced and the dangerous condition of stall. |
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| 104. |
What are the two principal processes of air traffic management?(a) Air traffic control and traffic flow management(b) Air traffic control and Aircraft system maintenance(c) Traffic flow management and Aircraft system maintenance(d) Aircraft system maintenance and Radio communication |
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Answer» The correct option is (a) Air traffic control and traffic flow management Explanation: The purpose of air traffic management is safe, efficient, and expeditious movement of the aircraft in the airspace. Its two major principles are air traffic control and traffic flow management. |
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| 105. |
What is the frequency band used by the ACLS?(a) Ka band(b) S band(c) C band(d) E band |
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Answer» The correct choice is (a) Ka band To explain: Two electronic instrument landing systems are found o all large U.S. carriers. Th ACLS involves two identical conically scanned Ka band radars set aft of the island about 125 and 135ft above the water line. |
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| 106. |
What is added to SPN-42 to eliminate wandering of the echo skin?(a) AESA(b) Aircraft beacon(c) PESA(d) Helical antenna |
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Answer» Correct choice is (b) Aircraft beacon The best explanation: The SPN-42 was retrofitted with a small X-band parabola when aircraft beacons were added to eliminate errors caused by wandering of the echo skin. |
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| 107. |
Which of the following is false with respect to ACLS?(a) Zero visibility landing is possible(b) Uses Ka band radars(c) Compensated for carrier roll, heave and pitch(d) Only handle one aircraft at a time |
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Answer» Correct answer is (d) Only handle one aircraft at a time To explain I would say: The two identical conically scanned radar antennas can track two aircraft simultaneously and, if desired, can uplink guidance signals to autopilots. |
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| 108. |
Which of the following is not true with respect to WAAS?(a) Provides WADGPS corrections(b) Uses ground integrity broadcast(c) Provide precision approaches for Category III C(d) Provide GPS ranging function |
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Answer» Correct choice is (c) Provide precision approaches for Category III C The explanation is: WAAS addresses the limitations by providing Wide area differential GPS error correction, a ground integrity broadcast, and a GPS ranging function from three or four geostationary satellites providing additional availability. |
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| 109. |
What is the speed of the aircraft relative to the ground called as?(a) Relative speed(b) Inertial speed(c) Ground speed(d) True airspeed |
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Answer» Correct choice is (c) Ground speed Explanation: When you stand on the ground with a radar speed gun pointing at the aircraft, the speed measured is called the ground speed and is measured relative to the ground. True airspeed is measured relative to the wind. |
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| 110. |
What is one of the main objectives of a military aircraft design?(a) High heat signature(b) Low RCS(c) High RCS(d) Highly stable configuration |
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Answer» Correct option is (b) Low RCS Explanation: Military aircraft usually wish to have a very low RCS or radar cross section so that they are stealthy and undetectable on the enemy’s primary radar. RCS can be reduced by various methods like using radar energy absorbing materials on the surface of the aircraft and not having sharp corners on the aircraft which are more likely to reflect radio energy back to the radar antenna. |
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| 111. |
Which of the following is done to reduce the static defect?(a) Streamlined configuration of the whole aircraft(b) Less weight as payload(c) Wind tunnel tests to find spots of body-flow interference(d) Deploy Flaps and slats |
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Answer» The correct option is (c) Wind tunnel tests to find spots of body-flow interference Easy explanation: Various wind tunnel tests are done to predict the optimum location for the static port so that the interference of the flow with the body is minimum. Since static defect is predictable, it can be corrected in the air-data computer. |
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| 112. |
Which of the following errors are not rectified by LDGPS?(a) Satellite ephemerides(b) Ionosphere propagation effects(c) Multi-path signal interference(d) Clock offset |
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Answer» Correct choice is (c) Multi-path signal interference The best explanation: LDGPS operation leads to the nearly complete cancellation of errors due to satellite ephemerides, clock offset, selective availability, and ionospheric propagation, leaving mainly those errors due to multipath signal interference and receiver noise. |
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| 113. |
The relative speed of the aircraft with respect to the carrier deck is _________(a) Lower(b) Greater(c) Zero(d) Indifferent |
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Answer» The correct answer is (a) Lower To elaborate: Jet aircraft approach the carrier deck with at airspeeds up to 125 knots. Their speed relative to the deck is lower due to the “wind over the deck,” which is normally about 30 knots. |
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| 114. |
What are the tubes in the aircraft that carry the air pressure to the instruments is called as?(a) Pneumatic plumbing(b) Pressure lines(c) Pressure tubes(d) Blue lines |
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Answer» Right option is (a) Pneumatic plumbing The best I can explain: Pipes that carry the air pressure sensed from the pitot tube or the pitot-static tube to the air data computer and the various other flight instruments such as the airspeed indicator, altitude indicator and the vertical speed indicator is collectively referred to as pneumatic plumbing. |
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| 115. |
What is the frequency in which the DME transmits?(a) 50Mhz above or below the received frequency(b) 20Mhz above the received frequency(c) 40Mhz below the received frequency(d) 63Mhz above or below the received frequency |
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Answer» Correct option is (d) 63Mhz above or below the received frequency To elaborate: The Ground beacon in the DME receives the airborne pulses, and after a 50μs delay, retransmits them back to the aircraft on a frequency 63Mhz above or below the airborne transmitting frequency. Here the frequency received by the DME is the Airborne transmitting frequency. |
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| 116. |
What is the beam width for a half wave dipole antenna?(a) 90°(b) 180°(c) 50°(d) 250° |
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Answer» Correct option is (a) 90° For explanation I would say: The beam width is measured between the points on the radiation curve that are 3 dB down from the maximum amplitude of the curve. The maximum amplitude of the pattern occurs at 0° and 180°. The 3-dB down points are 70.7 percent of the maximum. The angle formed with two lines extending from the center of the curve to these 3-dB points is the beam width. The beam width is 90°. The smaller the beam width angle, the more directional the antenna. |
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| 117. |
The reduction of glide slope gain is called as________(a) Auto throttle(b) Auto gain(c) Auto attenuation(d) Gain scheduling |
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Answer» Right option is (d) Gain scheduling Easy explanation: During the final approach the glide slope gain in the auto land system is reduced in a programmed fashion and is called gain scheduling. Supplementary sensors must supply the vertical guidance below 100ft. |
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| 118. |
What can be added to reduce signal ambiguity in a loop antenna?(a) Low noise amplifier(b) Amplifiers(c) Sense antenna(d) Increase the antenna size |
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Answer» Right choice is (c) Sense antenna To explain: The horizontal pattern of the loop antenna is a figure of eight which has two null positions 180° apart. This ambiguity will cause the system to give the same indication whether it is pointing toward a station or away from it. A sense antenna can be added when the signal ambiguity must be resolved. |
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| 119. |
Auto land system is a must for _________ and above?(a) Category I(b) Category II(c) Category III(d) Category IV |
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Answer» The correct answer is (b) Category II The best explanation: Air carrier aircraft that are authorized for precision approach below Category II must have an automatic landing system. Auto land systems use information from various landing systems like ILS Tacan and at some cases even GPS to safely land the aircraft. |
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| 120. |
What is used to combine the output of the two fixed loop antenna that are placed at right angles to each other?(a) Oscilloscope(b) Spectrum analyzer(c) Mixer(d) Goniometer |
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Answer» Right option is (d) Goniometer Explanation: The goniometer has two sets of fixed windings at right angles to each other, each set connected to one loop. It combines the output from the loop antenna into miniature a magnetic field in which a rotor can operate. |
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| 121. |
Which of the following is not an advantage of NDB?(a) Inexpensive(b) Omnidirectional(c) Accuracy depends on airborne equipment(d) No mountain and night effect |
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Answer» The correct answer is (d) No mountain and night effect Easiest explanation: NDB uses ground waves which follow the curvature of earth. They are inexpensive and independent of accuracy issues but suffer from night effect and mountain effect. Mountain effect is the distortion of ground wave in terrain of nonuniform character. |
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| 122. |
What is the speed reduction in a typical jet aircraft during the flare?(a) 95-100%(b) 75-82%(c) 50-55%(d) 5-10% |
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Answer» Correct choice is (d) 5-10% Explanation: Since during a flare maneuver the angle of attack is increased both lift and drag is increased. The excess lift causes upward acceleration to reduce the rate of descent and the increase in drag accounts for the reduction in the speed of the aircraft. |
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| 123. |
______________ provides deviation when the aircraft is displaced laterally from the vertical plane of the runway?(a) Localizer(b) Glide slope transmitter(c) DME(d) Marker beacons |
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Answer» Correct answer is (a) Localizer For explanation I would say: The localizer establishes a radiation pattern in space the provides a deviation signal in the aircraft when the aircraft is displaced laterally from the vertical plane containing the runway center line. |
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| 124. |
What is the signal that are added to the localizer signal, if the beam is narrow, to provide signal coverage?(a) Localizer plus(b) Difference signal(c) Sum signal(d) Clearance signal |
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Answer» Correct choice is (d) Clearance signal The explanation: When the localizer CSB pattern is narrow, to reduce reflections from buildings and other aircraft, the system requires the addition of “clearance” signals to provide 35° coverage in both directions. |
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| 125. |
Which one of the following is the basic vertical reference in all forms of heading and attitude devices?(a) Line perpendicular to artificial horizon(b) Earth’s gravitational field(c) Line perpendicular to actual horizon(d) Earth’s magnetic field |
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Answer» Correct option is (b) Earth’s gravitational field For explanation I would say: The basic vertical reference in all forms of heading and attitude reference devices is the Earth’s gravitational field. The direction of Earth’s gravitational field can be sensed with great accuracy in stationary systems. However, when the platform moves, all the instruments indicate the vector sum vehicle acceleration and local gravity. |
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| 126. |
Which of the following is used to sense aircraft magnetic fields?(a) Magnetic compass(b) Airborne magnetometer(c) Accelerometer(d) Gyroscope |
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Answer» Right answer is (b) Airborne magnetometer Explanation: Aircraft have magnetic fields that add to the Earth’s field and are sensed by the airborne magnetometers. The induced error, called deviation, can be 10° or more. |
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| 127. |
Satellite signals are refracted by the ionosphere.(a) True(b) FalseI got this question during an internship interview.I want to ask this question from Atmospheric Effects on Satellite Signals in division Satellite Radio Navigation & Inertial Navigation of Avionics |
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Answer» The correct choice is (b) False To explain I would say: Below 30MHz frequency the ionosphere almost acts like a mirror reflecting the signal back to Earth. At higher frequencies, such as those used in satellite communication, radio waves pass through the atmosphere. |
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| 128. |
Which of the following makes the existence of ionosphere possible?(a) Rotation of the Earth(b) Ultraviolet radiation from sun(c) Solar flares(d) Radiation from distant stars |
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Answer» Right option is (b) Ultraviolet radiation from sun For explanation I would say: The ionosphere owes its existence to the ultraviolet radiation from the sun. The photons possess a certain amount of energy which is enough to break down electrons from their parent atom. The result is a large number of free, negatively charged, electrons and positively charged atoms and molecules called ions. |
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| 129. |
Which of the following is not the angle between the horizontal component of B and true north?(a) Magnetic declination(b) Magnetic variation(c) Dip angle(d) Magvar |
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Answer» Correct option is (c) Dip angle To explain: The magnetic declination, also called the magnetic variation or magvar, is the angle between the horizontal component of B and true north. Navigators use ‘magvar’ in order not to confuse astronomical declination with magnetic declination. |
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| 130. |
What is the orientation of the Earth’s magnetic axis with respect to its spin axis?(a) 2°(b) 0°(c) 11°(d) 24° |
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Answer» Right answer is (c) 11° The explanation is: The Earth’s magnetic field is produced by a bar magnet oriented 11°away from the spin axis and passing within a hundred kilometers of its center. |
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| 131. |
What is the purpose of one shot multivibrator?(a) Trigger all AND gates at clock frequency(b) Trigger all OR gates at clock frequency(c) Trigger all AND gates at signal frequency(d) Trigger all OR gates at signal frequency |
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Answer» The correct choice is (a) Trigger all AND gates at clock frequency To elaborate: The one-shot multivibrator is used to trigger all the decoder AND gates at the clock frequency. It produces an output pulse whose duration has been set to the desired sampling interval. |
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| 132. |
Device that causes the magnitude of pressure to change when the aircraft speed nears zero are called ______(a) Airspeed indicator(b) Low speed indicators(c) Stall indicators(d) Rotating anemometer |
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Answer» Correct answer is (d) Rotating anemometer The best I can explain: Rotating anemometer increases the magnitude of pressure change caused by the change in airspeed when the aircraft airspeed is near zero. They are used in low omni range airspeed systems for helicopters. |
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| 133. |
Which of the following statements is true with respect to PCM?(a) The parallel binary data is converted into serial before transmission(b) Analog data is transmitted directly(c) Analog signal is amplified before transmission(d) The analog signal is converted into parallel binary data before transmission |
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Answer» The correct option is (a) The parallel binary data is converted into serial before transmission The explanation: The analog signal is converted into a digital signal. Since the converted digital signal is parallel bits of data, it has to be converted to serial before it can be multiplexed and transmitted. |
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| 134. |
Which of the following device was used in early TDM/PAM telemetry systems?(a) Commuter(b) Linear switch(c) Logic gates(d) DSP |
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Answer» The correct choice is (a) Commuter Easy explanation: Multiplexers in early TDM/PAM telemetry systems used a form of rotary switch known as a commutator. Multiple switch segments were attached to the various incoming signals while a high-speed brush rotated by a dc motor rapidly sampled the signals as it passed over the contacts. |
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| 135. |
Which of the following device is used to demultiplex the received signal?(a) Allpass filters(b) Bandpass filters(c) Bandstop filters(d) Differential filters |
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Answer» The correct answer is (b) Bandpass filters Explanation: A receiver picks up the signal and demodulates it, recovering the composite signal. This is sent to a group of bandpass filters, each centered on one of the carrier frequencies. Each filter passes only its channel and rejects all others. A channel demodulator then recovers each original input signal. |
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| 136. |
Which of the following type of multiplexing uses pulse code modulation?(a) Frequency division multiplexing(b) Time division multiplexing(c) Code division multiplexing(d) Amplitude limited multiplexing |
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Answer» The correct answer is (b) Time division multiplexing Easy explanation: The most popular form of TDM uses pulse-code modulation (PCM), in which multiple channels of digital data are transmitted in serial form. Each channel is assigned a time slot in which to transmit one binary word of data. The data streams from the various channels are interleaved and transmitted sequentially. |
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| 137. |
What device is used to demodulate a time division multiplexed analog wave?(a) High pass filter(b) Low pass filter(c) Band stop filter(d) Attenuator |
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Answer» Correct answer is (b) Low pass filter Explanation: the analog signal is converted to a series of constant-width pulses whose amplitude follows the shape of the analog signal. The original analog signal is recovered by passing it through a low-pass filter. In TDM using PAM, a circuit called a multiplexer (MUX or MPX) samples multiple analog signal sources; the resulting pulses are interleaved and then transmitted over a single channel. |
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| 138. |
What type of multiplexing is widely used in cellphones?(a) Time division multiplexing(b) Frequency division multiplexing(c) Code division multiplexing(d) Spatial multiplexing |
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Answer» Right answer is (c) Code division multiplexing The explanation is: Another form of multiple accesses is known as code-division multiple access (CDMA). It is widely used in cell phone systems to allow many cell phone subscribers to use a common bandwidth at the same time. This system uses special codes assigned to each user that can be identified. CDMA uses a technique called spread spectrum to make this type of multiplexing possible. |
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| 139. |
Transmission of modes reply at regular interval to aid TACS is called ________(a) Garble(b) Squitter(c) Fruit(d) Pulsed Radar |
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Answer» The correct option is (b) Squitter To explain: An important transponder characteristic that aids TCAS is the transmission of a mode S reply at quasi-random intervals of about 1 sec, which is called squitter. |
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| 140. |
Which of the following navigational systems is most stealthy?(a) Secondary surveillance radar(b) VOR(c) Celestial navigation(d) SONAR |
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Answer» The correct choice is (c) Celestial navigation To explain: In celestial navigation, the position is computed by measuring the elevation and azimuth of celestial bodies relative to the navigational coordinate frame at precisely known times. Since it is a completely passive system, it is considered to be stealthy and is used in special purpose high altitude aircraft in conjunction with an inertial navigator. |
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| 141. |
Time division multiplexing: Digital signal:: Frequency division multiplexing:?(a) Pulse code modulated signal(b) Continuous wave signals(c) Analog signal(d) Pulse position modulated signal |
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Answer» The correct choice is (c) Analog signal To explain I would say: The two most common types of multiplexing are frequency-division multiplexing (FDM) and time-division multiplexing (TDM). Two variations of these basic methods are frequency-division multiple access (FDMA) and time-division multiple access (TDMA). In general, FDM systems are used for analog information and TDM systems are used for digital information. |
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| 142. |
Which of the following is not an advantage of time division multiplexing?(a) Signal interference is less(b) More flexible(c) Full channel can be used for every signal(d) Fast data transfer |
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Answer» Right answer is (d) Fast data transfer The explanation is: Since the time available for transmission is shared by all the signals that are modulated, Time division multiplexing is not fast when compared with other multiplexing techniques. However, for applications such as telemetry, with a high sampling rate, the speed of time division multiplexing is sufficient to meet the requirements. |
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| 143. |
Which circuit does the actual multiplexing process in frequency division multiplexing?(a) Linear mixer(b) Oscillator(c) RF amplifier(d) Duplexer |
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Answer» The correct choice is (a) Linear mixer Best explanation: The modulator outputs containing the sideband information are added algebraically in a linear mixer; no modulation or generation of sidebands takes place. The resulting output signal is a composite of all the modulated subcarriers. This signal can be used to modulate a radio transmitter or can itself be transmitted over the single communication channel. Alternatively, the composite signal can become one input to another multiplexed system. |
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| 144. |
The transmission of multiple signals in a common frequency without interference is called _______(a) Time division multiplexing(b) Frequency division multiplexing(c) Code division multiplexing(d) Spatial multiplexing |
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Answer» Right choice is (d) Spatial multiplexing Best explanation: Spatial multiplexing is the term used to describe the transmission of multiple wireless signals on a common frequency in such a way that they do not interfere with one another. One way of doing this is to use low-power transmissions so that the signals do not interfere with one another. When very low power is used, the signals do not travel very far. The transmission distance is a function of the power level, frequency, and antenna height. |
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| 145. |
What is the individual carrier frequency of each signal called?(a) Subcarrier(b) Frequency carrier(c) Modulated carrier(d) Coded carrier |
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Answer» The correct choice is (a) Subcarrier Best explanation: Each signal to be transmitted feeds a modulator circuit. The carrier for each modulator (fc) is on a different frequency. The carrier frequencies are usually equally spaced from one another over a specific frequency range. These carriers are referred to as subcarriers. |
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| 146. |
Which of the following is not a requirement of transmission lines?(a) Minimum attenuation of signal(b) Should not radiate signal(c) High power signal(d) Less noise |
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Answer» Correct choice is (c) High power signal Explanation: The primary requirements of a transmission line are that the line introduces minimum attenuation, less noise to the signal and the line did not radiate any of the signals as radio energy. All transmission lines and connectors are designed with these requirements in mind. |
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| 147. |
Which of the following is not a reason for redistributing TV signals through satellites rather than skywaves or spacewaves?(a) High frequency signal(b) Long distance communication(c) Economically feasible(d) Power requirements |
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Answer» The correct option is (d) Power requirements Easiest explanation: TV signals are being transmitted through satellites for redistribution. Because of the very high-frequency signals involved in TV transmission, other long-distance transmission methods are not technically or economically feasible. |
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| 148. |
For frequency division multiplexing who defines the channel bandwidth?(a) FCC(b) ARNIC(c) FAA(d) CCA |
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Answer» Correct answer is (a) FCC Best explanation: The bandwidths of radio channels vary, and are usually determined by FCC regulations and the type of radio service involved. Regardless of the type of channel, a wide bandwidth can be shared for the purpose of transmitting many signals at the same time. |
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| 149. |
Which one of the following does not fall under the positioning system?(a) Radio systems(b) Celestial systems(c) AHRS(d) Mapping navigation systems |
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Answer» Correct option is (c) AHRS The best explanation: There are three types of positioning systems radio systems, celestial systems and mapping navigation systems. AHRS or Attitude Heading Reference System use accelerometer and gyroscope and hence fall under the dead reckoning navigation system. |
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| 150. |
In RF tuning, _________ provides the final up conversion to the microwave frequency?(a) Fixed-frequency local oscillator(b) RF frequency synthesizer(c) Quartz oscillator(d) Magnetic oscillator |
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Answer» Correct answer is (b) RF frequency synthesizer For explanation I would say: In RF tuning, a mixer fed by a fixed-frequency local oscillator performs an initial up conversion to 700 MHz. Then a sophisticated RF frequency synthesizer applied to a second mixer provides up conversion to the final microwave frequency. |
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