On July 14, 2001, about 1840 eastern daylight time, a homebuilt Cuevas, Orlando S., Quick Silver MXL II Sport homebuilt airplane, N4305C, registered to an individual, operating as a 14 CFR Part 91 personal flight, collided with trees on initial climb from a beach near Arroyo, Puerto Rico. Visual meteorological conditions prevailed and no flight plan was filed. The airplane received substantial damage. The recreational-rated pilot reported serious injuries. The flight was originating at the time of the accident. According to a witness, he observed the airplane depart from a "strip of sandy beach" next to a resort apartment. He said the airplane was preparing for takeoff in an easterly direction en route to a nearby airport. The pilot applied "full throttle," the airplane rolled for a short distances "lifted off...climbed normally," and continued to gain altitude in a straight line when "...unexpectedly [it] started turning left toward the line of palm trees bordering the apartment complex." For a moment the witness felt the airplane would clear the trees when it disappeared from his view. He "immediately..…heard the noise of the propeller thrashing against the palm leaves, the engine stopped and [he] saw the aircraft plummet straight down from the [tree] top." In addition, he said "…..all the time to the moment of impact, the engine sounded as if it was delivering full power." According to the FAA inspector this same witness told him that this accident happened late in the afternoon, and you can find heavy gusty conditions during the month of July.