HISTORY OF FLIGHT On June 3, 2011, at 1530 eastern daylight time, an experimental amateur-built Comp Air CA4 amphibian airplane, N434JC, collided with water shortly after a water takeoff from Merritt Island Airport (COF), Merritt Island, Florida. The test flight was operated under the provisions of 14 Code of Federal Regulations (CFR) Part 91 with no flight plan filed. Visual meteorological conditions prevailed. The test pilot received minor injuries, and the airplane was substantially damaged. The pilot stated that after performing a water takeoff from COF, and after initial flap retraction to 10 degrees, the engine began to lose manifold pressure. The aircraft was unable to continue its climb, and the pilot subsequently initiated a turn to the northwest to keep the airplane over water and avoid populated areas. Engine power continued to decrease as the airplane was in the turn and the pilot prepared for a forced water landing. The airspeed had degraded to around 54 knots and the airplane was descending under control. The pilot attempted to flare for landing; however, the airplane landed hard, in a left wing-low attitude. The left float separated from the airplane, the right float folded upward and the airplane sank. A witness was on a boat when he observed the airplane lift off the water and fly about 50-100 yards at an altitude of 10 feet. The airplane then touched back down on the water, and as it approached a bank of mangroves in the water, it lifted off with a "fairly steep angle of attack." The witness stated the airplane appeared to stall at about 30 feet off the water and then rolled to the left, and struck the water in a "cart-wheel" attitude. PERSONNEL INFORMATION The pilot held an airline transport pilot certificate with ratings for airplane single-engine land and sea, multiengine and instrument airplane. He also held a flight instructor certificate with a rating for airplane single-engine land. His most recent first-class Federal Aviation Administration (FAA) medical certificate was issued on December 16, 2010. At that time he reported 24,000 hours of flight experience. According to the NTSB Pilot/Operator Report Form, submitted by the pilot, he reported 27,000 hours of total flight experience at the time of the accident, 11 of which were in the make and model of the accident airplane. The pilot also held an FAA repairman certificate and an FAA repairman experimental aircraft builder certificate. AIRCRAFT INFORMATION According to a representative of Comp Air (the airplane kit manufacturer), the kit was sold to the owner without an engine. The representative recommended the installation of a Lycoming IO-540 (260 horsepower) engine due to the floats that were to be installed on the airplane; however, the owner decided to install a Lycoming IO-360 (180 horsepower) engine. The special airworthiness certificate was issued for the airplane on March 25, 2011, and its first flight occurred on April 4, 2011. The owner hired the accident pilot to fly the airplane during its first 40 hours of test flight time. The 40 hours of flight time were required through the FAA operations limitations for the airplane, before the permanent airworthiness certificate could be issued. The pilot flew 12 flights of varying duration from April 4, 2011 until the accident flight. A total of 10.4 flight hours were accumulated during this period. The pilot recorded detailed notes of each flight, as well as recommendations to fix any abnormalities. According to his notes, during a flight on the day prior to the accident flight, the pilot recorded the following observations: "The power to weight ration exacerbates the poor low speed flying qualities of this particular wing, with the only realistic solution being to change the wings to ones of lower aspect ratio ("Hershey Bar" type) or repower in the 250-300 hp range (O-540, IO-540 Lycoming)." The accident flight was the airplane's first takeoff from the water. The previous flights departed from the paved runway at COF. According to the pilot, the airplane departed with 12 gallons of fuel in the left tank and 13 gallons of fuel in the right tank. METEOROLOGICAL INFORMATION The weather recorded at Patrick Air Force Base (COF), Cocoa Beach, Florida, at 1555, included wind from 070 degrees at 10 knots, 10 miles visibility clear skies, temperature 29 degrees C, dew point 20 degrees C, and altimeter setting of 30.04 inches mercury. WRECKAGE AND IMPACT INFORMATION Examination of the airplane by an FAA inspector found that the airplane impacted the water left wing low, separating the left float and collapsing the right float, allowing the airplane to sink. The FAA inspector scheduled a follow-up examination of the airplane and engine after it was removed from the water. However, despite clear instructions not to disassemble the airplane, the owner proceeded to do so prior to the FAA's examination. As a result, any evidence of a pre-impact mechanical anomaly was compromised. ADDITIONAL INFORMATION Although the cause for the loss of power could not be determined since the evidence was compromised, the pilot offered a possible explanation for the loss of power. Because the floats did not have spray rails installed, and the air intake for the engine was located on the lower right side of the cowling, the engine could have lost power due to water ingestion.