MACHMETER – Air – DGCA Question Bank For Politics

#1. How will mach meter indication respond if an aircraft is flying at constant CAS at FL 270 when it experiences a reduction in OAT?

No change.

Increase.

Decrease.

Increase or decrease depending on TAT.

#2. What is the LSS at 30000 ft if ambient temperature is -40°C?

579 Kts.

660 Kts.

584 Kts.

594 Kts.

#3. Which of the following best defines Mach number?

The ratio of TAS:LSS.

The ratio of LSS:TAS.

The ratio of CAS:LSS.

The ratio of ambient density to that at msl in the ISA.

#4. A mach meter comprises of?

A combination of ASI and altimeter.

A combination of VSI and altimeter.

An ASI with its scale marked in mach numbers.

An altimeter with its scale marked in mach numbers.

#5. What is the LSS at 50000 ft in the ISA?

542 Kts.

660 Kts.

573 Kts.

550 Kts.

#6. How will mach meter indication vary in a constant CAS cilmb?

Increase.

Decrease.

Increase then remain constant.

remain constant.

#7. What is the LSS at msl ISA?

600 Kts.

550 Kts.

750 Kts.

661 Kts.

#8. Mach meter Indications?

Vary with airspeed and temperature.

Vary only with airspeed.

Vary only with temperature.

Vary with density and altitude.

#9. How will mach meter indication respond if an aircraft passes through a cold front when flying at constant CAS and altitude?

Increase.

Decrease.

Remain constant.

Increase or decrease depending on altitude.

#10. How will the mach meter respond in a constant CAS climb if the static source becomes blocked?

Increase.

Decrease.

Remain constant.

Increase of decrease depending on airspeed.

#11. How will the mach meter respond in a constant TAS climb if the static source becomes blocked?

Increase.

Decrease.

Remain constant.

Increase or decrease depending on airspeed.

#12. The indications on a mach meter are independent of?

Dynamic pressure.

Ambient temperature.

Static pressure.

Total pressure.

#13. What happens to mach meter indication in a constant RAS climb?

Increases.

Decrease.

Increase then remains constant.

Increase unless in an inversion or lsothermal layer.

#14. What would happen if the static pipe became detached from the back of a mach meter in a pressurised aircraft at high altitude?

Under read.

Over read.

No effect.

Under read or over read depending on temperature.

#15. If an aircraft climbs at constant TAS from FL 200 to FL 400 the mach meter indication will?

Increase.

Decrease.

Increase then remain constant.

Decrease then remain constant.

#16. A mach meter is made up of?

An altimeter with a density capsule.

An ASI with an altitude capsule.

A VSI with a modified scale.

An ASI with a modified scale.

#17. VMO is calculated based on?

TAS.

RAS.

CAS.

EAS.

#18. Mach number is the ratio of?

IAS:TAS.

CAS:LSS.

TAS:LSS.

RAS:TAS.

#19. If the static source becomes blocked the mach meter will ________ as an aircraft climbs?

Over indicate.

Under indicate.

Not indicate.

Freeze.

#20. It temperature decreases when flying at constant CAS at FL 200, the mach meter indication will _ and the true mach number will _?

Increase Increase.

Decrease decrease.

Not change not change.

Not change increase.

#21. Mach meter indications?

Are temperature related.

Increase with temperature.

Decrease with temperature.

Are independent of temperature.

#22. The speed of sound at ISA msl is?

560 Kts.

550 Kts.

660 Kts.

670 Kts.

#23. If ambient temperature is -10°C, what is the mach number when TAS in 594 Kts?

0.5M.

0.75M.

0.94M.

1.5M.

#24. The speed of sound at 25000 ft ISA is?

600 Kts.

602 Kts.

604 Kts.

606 Kts.

#25. What is true mach number at 25000 ft ISA the TAS is 500 Kts?

0.75M.

0.83M.

0.90M

0.93M.

#26. A mach meter indicates mach number based on the ratio of?

Static pressure to pitot pressure.

Pitot pressure to static pressure.

Dynamic pressure to static pressure.

Static pressure to dynamic pressure.

#27. How will CAS respond if temperature increases by 5 degrees C when flying at a constant indicated mach number at FL290?

Increases

Decreases

Remains approximately constant.

Depends on conditions relative to ISA.

#28. What happens to TAT when an aircraft descends at constant indicated mach number?

Increases

Decreases

Remain constant.

Remains constant then increases.

#29. What is actually measured by a mach meter?

Pitot pressure.

The ratio of (pitot pressure - static pressure) : static pressure.

The ratio of static pressure to dynamic pressure.

The ratio of (static pressure + pitot pressure) : pitot pressure.

#30. When descending at constant CAS, the TAT and mach meter indications should?

Increase increase.

Increase decrease.

Increase then remain constant decrease.

Remain constant remain constant.

#31. Mach meter indications are derived from?

(Pr - Ps) Pr.

(Ps - PT)/Ps.

(Pr - Ps)/Ps.

(Ps - Pr)/PT.

#32. If temperature increases by 5 degrees C during a constant mach number descent, what will happen to CAS?

Increase by 5 Kts.

Increase by 10 Kts.

Remain constant.

Increase or decrease depending on whether conditions are above or below ISA.

#33. A mach meter compares?

(Pr - Ps) to Pr.

(Ps - Pr) to Ps.

(Pr - Ps) to Ps.

(Ps - Pr) to Pr.

#34. What does mach number represent?

The CAS of an aircraft as a fraction of the local speed of sound.

The local speed of sound as a fraction of the CAS of an aircraft.

The TAS of an aircraft as a fraction of the local speed of sound.

The local speed of sound as a fraction of the CAS of an aircraft.

#35. What is the local speed of sound at sea level if the ambient temperature is 20°C?

661 Kts.

666 Kts.

677 Kts.

680 Kts.

#36. If ambient temperature increases by 10 degrees, for an aircraft flying at constant TAS, the indicated mach number will and the true mach number will _?

Increase increase

Decrease decrease.

Not change increase.

Not change decrease.

#37. When climbing at constant mach number below the torpopause in the ISA, the CAS will?

Increase.

Decrease.

Remain constant.

#38. When descending at constant CAS, if temperature remains constant the indicated mach number will?

Remain constant.

Increase

Decrease

Increase exponentially.

#39. What should the mach meter indicate when flying at 500 kts TAS at FL 250, if the ambient temperature is -30° C?

0.52M

0.62M

0.72M

0.82M

Dgca Question Bank For Pilots

Results

#1. How will mach meter indication respond if an aircraft is flying at constant CAS at FL 270 when it experiences a reduction in OAT?

#2. What is the LSS at 30000 ft if ambient temperature is -40°C?

#3. Which of the following best defines Mach number?

#4. A mach meter comprises of?

#5. What is the LSS at 50000 ft in the ISA?

#6. How will mach meter indication vary in a constant CAS cilmb?

#7. What is the LSS at msl ISA?

#8. Mach meter Indications?

#9. How will mach meter indication respond if an aircraft passes through a cold front when flying at constant CAS and altitude?

#10. How will the mach meter respond in a constant CAS climb if the static source becomes blocked?

#11. How will the mach meter respond in a constant TAS climb if the static source becomes blocked?

#12. The indications on a mach meter are independent of?

#13. What happens to mach meter indication in a constant RAS climb?

#14. What would happen if the static pipe became detached from the back of a mach meter in a pressurised aircraft at high altitude?

#15. If an aircraft climbs at constant TAS from FL 200 to FL 400 the mach meter indication will?

#16. A mach meter is made up of?

#17. VMO is calculated based on?

#18. Mach number is the ratio of?

#19. If the static source becomes blocked the mach meter will ________ as an aircraft climbs?

#20. It temperature decreases when flying at constant CAS at FL 200, the mach meter indication will _________ and the true mach number will _________?

#21. Mach meter indications?

#22. The speed of sound at ISA msl is?

#23. If ambient temperature is -10°C, what is the mach number when TAS in 594 Kts?

#24. The speed of sound at 25000 ft ISA is?

#25. What is true mach number at 25000 ft ISA the TAS is 500 Kts?

#26. A mach meter indicates mach number based on the ratio of?

#27. How will CAS respond if temperature increases by 5 degrees C when flying at a constant indicated mach number at FL290?

#28. What happens to TAT when an aircraft descends at constant indicated mach number?

#29. What is actually measured by a mach meter?

#30. When descending at constant CAS, the TAT and mach meter indications should?

#31. Mach meter indications are derived from?

#32. If temperature increases by 5 degrees C during a constant mach number descent, what will happen to CAS?

#33. A mach meter compares?

#34. What does mach number represent?

#35. What is the local speed of sound at sea level if the ambient temperature is 20°C?

#36. If ambient temperature increases by 10 degrees, for an aircraft flying at constant TAS, the indicated mach number will ______ and the true mach number will _______?

#37. When climbing at constant mach number below the torpopause in the ISA, the CAS will?

#38. When descending at constant CAS, if temperature remains constant the indicated mach number will?

#39. What should the mach meter indicate when flying at 500 kts TAS at FL 250, if the ambient temperature is -30° C?

#20. It temperature decreases when flying at constant CAS at FL 200, the mach meter indication will _ and the true mach number will _?

#36. If ambient temperature increases by 10 degrees, for an aircraft flying at constant TAS, the indicated mach number will and the true mach number will _?