Guys I’ve know who have dunked their planes usually pull the radio and open up the RX to dry it out. When they go into salt water, they immediately dunk the whole radio (after removing from the plane) into freshwater to flush out the salt, then actually pulled the components apart in the fresh water bucket to make sure all the salt was removed, then let it all air dry in the sun. For fresh water, you want to open the RX up as soon as possible to dry it out. Servo’s, if it’s a quick dunk, most likely won’t get much if any water in them, but it doesn’t hurt to repack the gears with white lithium grease either.

For the engine, you want to remove disassemble it at the field as soon as possible and flush with fuel and coat everything with oil to prevent rusting.

I saw one guy dunk his plane 2 times in one day in the Atlantic (Ponce de Leon Inlet south of Daytona Beach). He pulled everything apart, cleaned and lubricated it, and flew again. He flew, dunked, cleaned, flew, dunked, cleaned, flew and flew again – 4 flights total that day with two dunks.

Hogflyer