RAD 15 – Radio Altimeter (RADALT) – LMS

📄 Detailed Notes ⚡ Cheat Sheet

Results

📄 Notes ⚡ Cheat Sheet

Q1. A radio altimeter is?

Aircraft based and indicates pressure altitude.

Ground based and employ microwaves.

Aircraft based and indicates true height.

Aircraft based and indicates true altitude.

Q2. A radio altimeter can be defined as a?

Self-contained on-board aid used to measure the true altitude of the aircraft.

Self-contained nn-board aid used to measure the true height of the aircraft.

Ground radio aid used to measure the true altitude of the aircraft.

Ground radio aid used to measure the true height of the aircraft.

Q3. In low altitude radio altimeters height measurement (above ground) is based upon?

A triangular amplitude modulation wave, for which modulation phase shift between transmitted and received waves after ground reflection is measured.

A frequency modulation wave, for which the frequency variation between the transmitted wave and the received wave after ground reflection is measured.

A pulse transmission, for which time between transmission and reception is measured on a circular scanning screen.

A wave transmission, for which the frequency shift by DOPPLER effect after ground reflection is measured.

Q4. The operating frequency range of a low altitude radio altimeter is?

5 GHz.

2700 MHz to 2900 MHz.

4200 MHz to 4400 MHz.

5400 MHz or 9400 MHz.

Q5. Approximate wavelength of Radio altimeter is…….

7 Cm

7 mm

0.7 m

70 mm

Q6. A radio altimeter measures?

Height above the ground or water over which the aircraft is flying.

True Altitude.

Pressure altitude.

Height above sea level.

Q7. For the landing configuration, a radio altimeter indicates?

Height of the aircraft above the ground.

Altitude.

Height of the flight deck above the ground.

Height of the main wheel above the ground.

Q8. A radio altimeter is?

Aircraft based and indicates pressure altitude.

Ground based and employ microwaves.

Aircraft based and indicates true height.

Aircraft based and indicates true altitude.

Q9. In low altitude radio altimeters, the reading is zero when main landing gear wheels are on the ground. For this, it is necessary to?

Accounts for signal processing time in the unit and apply a correction factor to the reading.

Change the display scale in short final, in order to have a precise readout.

Place the antennas on the bottom of the aeroplane.

Compensate residual altitude due to antennas height above the ground and coaxial cables length.

CORRECT ANSWER: Accounts for signal processing time in the unit and apply a correction factor to the reading.

WRONG ANSWER: Compensate residual altitude

Q10. A low altitude radio altimeter, used in precision approaches, has the following characteristics: 1. 1540 MHz to 1660 MHz range ; 2. pulse transmissions ; 3. frequency modulation ; 4. height range between 0 and 2500 ft ; 5. an accuracy of +/- 2ft between 0 and 500 ft.

1, 4 and 5

3 and 4

3 and 5

2, 3 and 5

Q11. Low altitude radio altimeters operate on the………. wavelength?

decimetric.

centimetric.

millimetric.

metric.

Q12. The operation of the radio altimeter of a modern aircraft is based on?

Pulse modulation of the carrier wave.

Amplitude modulation of the carrier wave.

A combination of frequency modulation and pulse modulation.

Frequency modulation of the carrier wave.

Q13. If there is a fault in the system the radalt display will?

Freeze.

Turn red and activate an aural warning.

Needle will disappear and an alarm flag will appear, possibly accompanied by an audio warning.

Turn red and activate visual and aural warnings.

Q14. For most radio altimeters, when a system error occurs during the approach the?

Audio warning signal sounds.

Height indication is removed.

DH lamp flashes red.

DH lamp flashes red and the audio signal sounds.

Q15. Radio altimeters are accurate only within the height range?

Zero ft to 2500 ft.

Zero to 500 ft.

Zero to 50 ft.

50 ft to 2700 ft.

Q16. The data supplied by a radio altimeter?

Is used only by the radio altimeter indicator.

Indicates the distance between the ground and the aircraft.

Is used by the automatic pilot in the altitude hold mode.

Concerns only the decision height.

Q17. During the approach, a crew reads on the radio altimeter the value of 650 ft. This is an indication of the true?

Altitude of the aircraft.

Height of the lowest wheels with regard to the ground at any time.

Height of the aircraft with regard to the runway.

Height of the aircraft with regard to the ground at any time.

Q18. A radio altimeter can be defined as a?