GPC - Glider Pilot Certificate Aerodynamics and Glider Performance Questions and Answers

Question 1

A glider pilot wants to maximize the time spent in the air to take advantage of a thermal. Which speed should the pilot aim to fly at?

Accepted Answer

Minimum sink speed

Answer

Best lift/drag ratio (L/D max) speed

Answer

Maneuvering speed (Va)

Answer

Never exceed speed (Vne)

Question 2

How does increasing the all-up weight of a glider (e.g., by adding water ballast) affect its performance, assuming the pilot flies at the correct corresponding airspeeds?

Accepted Answer

It has no effect on the best glide ratio but increases the best glide speed.

Answer

It decreases the best glide ratio (L/D max).

Answer

It increases the best glide ratio (L/D max).

Answer

It decreases both the best glide speed and the minimum sink speed.

Question 3

A pilot is flying a glider with a published best glide ratio of 40:1 in still air. From an altitude of 5,280 feet above the ground, what is the maximum horizontal distance the glider can travel?

Accepted Answer

211,200 feet

Answer

40 nautical miles

Answer

52.8 nautical miles

Answer

40 statute miles

Question 4

Which of the following aerodynamic forces acts perpendicular to the relative wind?

Accepted Answer

Lift

Answer

Drag

Answer

Weight

Answer

Thrust

Question 5

While on a cross-country flight, a glider pilot encounters a strong headwind when flying between thermals. To maximize the distance covered over the ground, the pilot should:

Accepted Answer

Fly faster than the best L/D speed.

Answer

Fly at the normal best L/D speed.

Answer

Fly slower than the best L/D speed.

Answer

Fly at the minimum sink speed.

Question 6

What is the primary reason high-performance gliders are designed with long, slender wings (a high aspect ratio)?

Accepted Answer

To reduce induced drag

Answer

To increase parasite drag

Answer

To improve maneuverability at low speeds

Answer

To increase the stall speed