The pilot of the float-equipped airplane reported that, while taking off from a lake, the airplane accelerated, became airborne and that, about 40 ft above the water, he retracted the flaps. The airplane pitched down, and the left wing dropped. He attempted to correct to no avail, and the airplane impacted the water. The airplane sustained substantial damage to the fuselage, empennage, and both wings. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. He added that he believed P factor caused the left roll because the airplane aerodynamically stalled and would not correct despite his attempts to do so. He also stated that he had accrued 5 hours in the airplane make and model, 2 hours of which occurred in the preceding 30 days. The pilot reported that it was a very windy, gusty day and that the wind was variable. An automated weather observation station located 15 miles west of the accident site reported that, about the time of the accident, the wind was from 300° at 14 knots, gusting to 20 knots. The airplane was departing to the south.