Exam quiz Principles of Flight (Balloon) - Quiz BPL Hot Air - Balloon Pilot License

Question 1

With pressure and temperature given, any gas being heavier or lighter than air depends on what?

Accepted Answer

On the molecule mass of the gas

Answer

On the mean kinetic energy of the molecules

Answer

On the content of water vapour in the gas

Answer

On the number of gas molecules

Question 2

At equilibrium the inner overpressure of a free balloon is highest at:

Accepted Answer

The upper pole.

Answer

At the lower opening.

Answer

At the center of the hull.

Answer

At the equator.

Question 3

The dynamic lift created by airflow across the top of the envelope of a balloon on the ground is referred to as?

Accepted Answer

False lift

Answer

Lower lift

Answer

Upper lift

Answer

Anti-ballast

Question 4

How do volume, density and temperature change when a gas is being compressed?

Accepted Answer

Volume decreases, density increases, temperature increases.

Answer

Volume decreases, density decreases, temperature decreases.

Answer

Volume decreases, density increases, temperature increases

Answer

Volume increases, density decreases, temperature decreases.

Question 5

Doubling the pressure of a dry gas at constant temperature results in a change of the volume to:

Accepted Answer

Half the previous value.

Answer

Double the previous value.

Answer

Four times the previous value.

Answer

A quarter of the previous value.

Question 6

The force resulting from the (positive) difference from load-bearing capacity and weight force, is referred to as:

Accepted Answer

Climb force

Answer

Upper force

Answer

Lift force

Answer

Load force

Question 7

Aerostatic lift, amongst other factors, depends on...

Accepted Answer

Air density.

Answer

Shape of the envelope.

Answer

On the speed.

Answer

Balloon mass.

Question 8

With regard to gases, which statement is correct?

Accepted Answer

Volume increases with increasing temperature and constant pressure.

Answer

Temperature increases with increasing volume and decreasing pressure.

Answer

Temperature decreases with increasing pressure and constant volume.

Answer

Pressure decreases with increasing temperature and constant volume.

Question 9

What impact may rain have on operation of a hot-air balloon?

Accepted Answer

Total mass and gas consumption increase

Answer

Rain drops hitting on the hull reduce the lift force.

Answer

The hull is deformed, which reduces lift.

Answer

The hull is cooled, resulting in less gas consumption.

Question 10

If heating is stopped and the parachute vent is not activated, a hot air-balloon reaches a final sinkrate of approximately:

Accepted Answer

6 m/s

Answer

2 m/s

Answer

10 m/s

Answer

20 m/s

Question 11

At which conditions does the arm blower have the highest effeiciency?

Accepted Answer

By completely filling the balloon opening with the air beam.

Answer

With as small distance to the balloon opening as possible.

Answer

By evenly swiveling for better air spreading.

Answer

By placing the blower inside the hull.

Question 12

The standard state of gases refers to which temperature?

Accepted Answer

25° C

Answer

15° C

Answer

0° C

Answer

5° C

Question 13

The final sinkrate of a hot-air ballon is achieved after descent over a vertical distance of:

Accepted Answer

250 - 450 m

Answer

1000 - 2000 m

Answer

50 - 100 m

Answer

500 - 1000 m

Question 14

The standard state of gases refers to which temperature?

Accepted Answer

25° C

Answer

0° C

Answer

15° C

Answer

5° C

Question 15

The vertical extend of air with pressure changing by 1% with 80 m difference in height is referred to as ...

Accepted Answer

Homogene

Answer

Inhomogene

Answer

Unstable

Answer

Stable

Question 16

According ISA, what is the density of air at MSL?

Accepted Answer

1.225 kg/m3

Answer

1.225 g/m3

Answer

1225 kg/m3

Answer

12.25 kg/m3

Question 17

The increase in load carrying capability by increasing the hull air temperature by the same temperature difference ...

Accepted Answer

Decreases with altitude.

Answer

Increases with balloon mass.

Answer

Increases with altitude.

Answer

Decreases with sinking.

Question 18

Which of the following statements is correct?

Accepted Answer

The density of hull air is lower than environmental air only if the hull temperature is higher than environmental temperature

Answer

The density of hull air is lower with decreasing environmental pressure

Answer

The density of hull air is higher with increasing environmental pressure

Answer

The density of hull air is lower than environmental air only if the hull temperature is lower than environmental temperature

Question 19

What statement is correct with regard to the density of a gas?

Accepted Answer

The density decreases with increasing temperature and constant pressure.

Answer

The density increases with increasing temperature and constant volume.

Answer

The density decreases with decreasing volume and constant temperature.

Answer

The density decreases with increasing temperature and constant volume.

Question 20

Changing the shape of the envelope of a free balloon, e.g. by a gust, results in:

Accepted Answer

Decrease in volume

Answer

Increase in lift.

Answer

Increase of displaced air.

Answer

Decrease in weight.

Question 21

The ratio between air pressures at different heights is referred to as:

Accepted Answer

Height number

Answer

Pressure number

Answer

Height value

Answer

Height ratio

Question 22

Which of the following statements is correct?

Accepted Answer

At higher altitude, sink rate in case of cooling is increased due to less drag by less density.

Answer

At higher altitude, sink rate by cooling is not increased because due to low density the mass inside the hull is also less.

Answer

Higher drag at higher altitude prevents increased sink rate in case of cooling.

Answer

Maximum sink rate must be equal at all altitudes as prescribed by design regulations.

Question 23

How does a gas react when released from a pressurized container?

Accepted Answer

The gas cools adiabatically due to expansion

Answer

The gas cools due to thermal contact with environmental air.

Answer

The gas heats adiabatically due to expansion.

Answer

The gas condenses inside the envelope.

Question 24

The aerostatic lift corresponds to which force?

Accepted Answer

The weight of the displaced air

Answer

The weight of the balloon less ballast

Answer

The dynamic force due to airstream across the top of the hull

Answer

The drag due to airstream around the balloon envelope

Question 25

What is the relationship between pressure and volume of a dry gas at constant temperature?

Accepted Answer

The volume is inversely proportional to pressure

Answer

The volume increases proportional with pressure

Answer

The volume increases by a factor of 4 with double pressure

Answer

The ration between pressure and volume is constant

Question 26

What effect has an increase in air temperature inside the hull of a hot air balloon by a given difference in temperature?

Accepted Answer

The increase in load carrying capacity decreases with height.

Answer

The increase in load carrying capacity increases with height.

Answer

The increase in rate of climb increases with height.

Answer

The reduction in sink rate increases with height.

Question 27

What cause may result in a reduction of volume of a free balloon?

Accepted Answer

A gust

Answer

Reduction in mass

Answer

Cooling of environment air

Answer

Increase in hull temperature

Exam simulation Principles of Flight (Balloon) Quiz BPL Hot Air - Balloon Pilot License

Exam simulation BPL Hot Air Principles of Flight (Balloon) 100 questions on 120 minutes