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weight reduction in level flight

  • brendanovens
  • Topic Author

brendanovens created the topic: weight reduction in level flight

just doing my final aerody test 1 in cpl book
and a question i have just come across is
An air craft is in straight and level flight at a constant power. As weight reduces with fuel burn off, level flight may be maintained by
A: incresaing indicated air speed and raising the nose
B: increasing the indicated airspeed and lowering the nose
C: decreasing the indicated airspeed and raising the nose
D: decreasing the indicated airspeed and lowering the nose

Now the correct answer is b i am struggling to understand why you would need to increase the airspeed if you have just lost weight i understand lowering the nose but why increase speed if the total reaction between weight and drag has been reduced would you be flying at a faster indicated air speed, so to maintain constant speed reduce power and lower nose.

Struggling to grasp this concept can someone send me a lightning bolt to the forehead
brendan
#1

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  • ScottB

ScottB replied the topic: weight reduction in level flight

Hi bredanovens,

From what i can grasp from the concept,

To maintain S/L Flight with the reduction in weight, you need to reduce the lift equally to maintain equilibrium, this can be done by lowering the nose or reducing the power. As the question says the "Power is kept constant" the only way to reduce the lift is to lower the nose.
With the reduction in weight and AoA, the aircraft with the "constant power" will increase in speed by itself.

If anyone can explain this more feel free :)

Scott
#2

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