Question

The minimum glide angle of the unpowered flight depends on

• A. lift to drag ratio is maximum
• B. rate of descent is minimum
• C. lift force
• D. lift to weight ratio is maximum

Hint:

Gliders aim for max \( L/D \) for longest glide distance per unit altitude lost.

Answer 1

The Correct Option is A

In aerospace engineering, the glide angle during an unpowered flight is an essential parameter and it is primarily influenced by the aircraft's aerodynamics. The glide angle is determined by the lift-to-drag ratio (L/D). When the lift-to-drag ratio is maximized, the glide angle reaches its minimum. This relationship is based on the principle that for the longest glide distance, an aircraft should minimize drag while maximizing lift, effectively optimizing the glide path.

The answer to the question of what the minimum glide angle depends on is therefore the option: "lift to drag ratio is maximum". This is because:

• Lift-to-Drag Ratio (L/D): A higher L/D ratio means better aerodynamic efficiency, allowing the aircraft to travel further horizontally for each unit of altitude lost. This results in a smaller glide angle.
• Rate of Descent: Although a minimum rate of descent might be desirable, it is not directly responsible for determining the minimum glide angle.
• Lift Force: While critical for flight, it is the ratio of lift to drag that primarily impacts glide angle.
• Lift-to-Weight Ratio: Although it affects flight performance, it is not directly related to achieving the minimum glide angle.