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

Question 1

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 ratio between pressure and volume is constant

Question 2

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 3

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 4

The standard state of gases refers to which temperature?

Accepted Answer

25° C

Answer

0° C

Answer

15° C

Answer

5° C

Question 5

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 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

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 8

The final sinkrate of a hot-air balloon 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 9

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

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 10

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 11

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

Question 12

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

Accepted Answer

Air density

Answer

Shape of the envelope

Answer

On the speed

Answer

Balloon mass

Question 13

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 14

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 15

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 16

The standard state of gases refers to which temperature?

Accepted Answer

25° C

Answer

15° C

Answer

0° C

Answer

5° C

Question 17

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 18

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 19

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 20

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 21

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

Accepted Answer

Homogeneous

Answer

Inhomogeneous

Answer

Unstable

Answer

Stable

Question 22

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 23

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 decreases

Answer

Volume increases, density decreases, temperature decreases

Question 24

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 25

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 26

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 27

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

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

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