Given maximum auto winch tow speed 69 mph, surface wind 5 mph, wind gradient 5 mph, what should the auto winch speed be when a glider reaches an altitude of 200 feet?

Given maximum auto winch tow speed 69 mph, surface wind 5 mph, wind gradient 5 mph, what should the auto winch speed be when a glider reaches an altitude of 200 feet?

• A. 69 mph
• B. 44 mph
• C. 25 mph
• D. 55 mph

Answer: (B)

The main idea is to set the tow speed so the glider reaches the 200 ft height with a safe, controlled airspeed when a wind gradient is present. A wind gradient means the wind strength changes with altitude. If the wind increases with height (a gradient), the glider encounters a stronger headwind as it climbs, which changes the relationship between the winch’s ground speed and the glider’s airspeed. To keep the glider from accelerating too fast through the air as it rises, the winch speed must be reduced from the maximum. In this scenario, accounting for the wind that exists at 200 ft due to the gradient leads to a tow speed around 44 mph rather than holding the maximum 69 mph. Going too fast would push the glider's airspeed higher than desired during the climb, while going much slower would risk insufficient tow to reach the target altitude safely.

The main idea is to set the tow speed so the glider reaches the 200 ft height with a safe, controlled airspeed when a wind gradient is present. A wind gradient means the wind strength changes with altitude. If the wind increases with height (a gradient), the glider encounters a stronger headwind as it climbs, which changes the relationship between the winch’s ground speed and the glider’s airspeed.

To keep the glider from accelerating too fast through the air as it rises, the winch speed must be reduced from the maximum. In this scenario, accounting for the wind that exists at 200 ft due to the gradient leads to a tow speed around 44 mph rather than holding the maximum 69 mph. Going too fast would push the glider's airspeed higher than desired during the climb, while going much slower would risk insufficient tow to reach the target altitude safely.