Final answer:
To avoid hydroplaning, it's recommended to drive significantly below 55 mph (89 km/h), especially in heavy rain or on wet roads. This speed allows the tires to better displace water and maintain control. Factors such as tire condition and road surface can adjust this guideline.
Step-by-step explanation:
To avoid hydroplaning, it's essential to maintain a speed that allows the tire tread to effectively displace water and maintain contact with the road surface. While specific speeds can vary depending on tire condition, vehicle weight, and water depth, a commonly cited safe speed to avoid hydroplaning is significantly below 55 miles per hour (89 kilometers per hour).
This recommendation changes with factors like tire quality and wear, but it's a general rule to reduce speed during heavy rain or standing water conditions.When a vehicle exceeds this threshold, the tires may start to ride on top of the water, causing a loss of traction and control known as hydroplaning. NASA's research on aerodynamic drag and friction provides some insights into the forces at play during vehicle operation at higher speeds.
While this research pertains more to fuel efficiency and the various effects of air drag at highway speeds, the underlying principle of maintaining control by managing speed and traction is also relevant for avoiding hydroplaning.
Driving at speeds above the recommended limit increases the risk of hydroplaning. Additionally, the ideal speed for navigating curves, especially those that are steeply banked, can provide a guideline. For example, the ideal speed for a 100 m radius curve banked at 65.0°, taking friction into account, would be very high - even up to 165 kilometers per hour, under controlled race track conditions.
However, these speeds are not practical or safe for public roads, especially in wet conditions. It is safer to drive well within the speed limit and adjust speed downward based on road conditions to maintain safe traction.