18. Forces acting on an aircraft (straight and level flight)

Question 1

The four main forces acting on an aircraft in flight are …….., …….., …….., and ……..

Answer 1

Lift; weight; thrust; drag

Question 2

In straight and level flight at a constant airspeed, the aircraft is in equilibrium, with the weight counteracted by the …….. and the drag counteracted by the ……..

Answer 2

Lift; thrust

Question 3

To accelerate an aircraft in level flight:

a) thrust must exceed drag
b) thrust must equal drag
c) drag must exceed thrust
d) thrust must equal weight

Answer 3

A

Question 4

Complete the following phrase: “power plus attitude equals ……..”

Answer 4

Performance

Question 5

To fly faster but remain in level flight the nose attitude must be progressively (raised / lowered) at the same time as power is applied.

Answer 5

Lowered

Question 6

As airspeed increases in level flight, drag builds up until it is equal to …….. and the forces will return to a new state of equilibrium

Answer 6

Thrust

Question 7

After an increase of speed in level flight, the nose attitude will be (higher / lower) than previously.

Answer 7

Lower

Question 8

To decelerate an aircraft in level flight:

a) thrust must exceed drag
b) thrust must equal drag
c) drag must exceed thrust
d) drag must equal weight

Answer 8

C

Question 9

After a decrease in speed in level flight, the nose attitude will be (higher / lower) than previously

Answer 9

Higher

Question 10

In steady -state flight, the sum of the opposing forces acting on an aircraft (is / is not) zero.

Answer 10

Is

Question 11

What two factors determine the performance of an aircraft?

Answer 11

Power and attitude

Question 12

In flight, the lift/weight and the thrust/drag pitching couples rarely balance out and it is the function of the …….. to provide the necessary stabilizing force

Answer 12

Tailplane (or horizontal stabilizer)

Question 13

The maximum speed possible in straight and level flight occurs when the power …….. is equal to the power ……..

Answer 13

Available; required

Question 14

The minimum speed straight and level is usually when the …….. angle of attack is reached.

Answer 14

Stalling

Question 15

Maximum range in level flight is achieved when the …….. distance is flown for the …….. amount of fuel used.

Answer 15

Maximum; minimum (or least)

Question 16

Maximum endurance will be achieved when the aircraft remains airborne for the greatest amount of …….. for the …….. amount of fuel used.

Answer 16

Time; least