How pilots stop airplanes from hydroplaning on wet runways?
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People have all mentioned various parts but the real answer is a combination of several things.
Runway design plays a huge part of it, they aren’t perfectly flat so water runs off of them instead of pooling and almost all large commercial runways are grooved with channels that are specifically engineered to remove water. Runway condition is also monitored and reported regularly to pilots before takeoff and landing.
Tire design is another huge part, airplanes don’t have racing slicks for tires, they have grooved patterns that are also specifically engineered to help remove water and prevent hydroplaning. Hydroplaning is also governed by basic physics, the speed at which a tire will hydroplane is 9*SqRoot(PSI) so it is known when both the main and nose gear are susceptible to it. This formula is also before the tire tread is factored in so real world will be better than that. As others have also said, airplanes have very smart antilock brake systems, far more advanced than anything you find on cars.
Finally, the way commercial planes land and stop helps with this. Thrust reversers are used for stopping, although they often do not have a huge impact because they take a second or so to deploy and then a bit longer to spool up in reverse. Either way, they do not need rubber on concrete contact to induce deceleration. More than anything the spoilers give a huge advantage to stopping. They dump lift and increase weight on wheels which helps to push the rubber through the water layer (that formula is also just for fighting gravity, not additional aerodynamic forces shoving the wheels downward). Add in that reverse thrust also points upwards and pushes down, the tires are designed for it, the ABS can account for it and the runway was designed to minimize it and it’s not that much of an issue anymore, especially when you calculate a unique landing distance for that specific airport’s current conditions and you know you have enough runway available for the aircraft’s ability to stop in those conditions.
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