HISTORY OF FLIGHTOn October 27, 2012, about 0925 mountain standard time, an experimental amateur-built JeffAir Barracuda, N19GS, was substantially damaged when all three landing gear collapsed after touchdown on runway 6 at Payson airport (PAN), Payson, Arizona. Neither the pilot/owner nor his passenger was injured. The personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no FAA flight plan was filed for the flight. According to the pilot, the airplane landing gear system was equipped with three green annunciation lights, which illuminate when the landing gear is fully extended for landing, and three amber annunciation lights, which illuminate when the landing gear is fully retracted. On departure from Ernest A. Love field (PRC), Prescott, Arizona, for PAN, the pilot noticed that the nose landing gear (NLG) amber light illuminated about 5 to 8 seconds after the two main landing gear (MLG) lights; normally all three illuminate approximately simultaneously. The pilot was uncertain whether there really was a problem, and the airplane operated normally for most of the remainder of the flight. In the traffic pattern at PAN, after the pilot selected the landing gear to the extended position, he observed that the two green MLG lights illuminated, but the green NLG light did not. He conducted a low flyby of the airport, and a ground observer radioed that the NLG appeared to be fully extended. The pilot then conducted a normal landing, but the NLG retracted when the pilot lowered the nose of the airplane. Very shortly thereafter, the two MLG then retracted, and the airplane slid to a stop on the runway. Portions of both MLG assemblies pushed up through the upper wing skins after the unintentional retraction. The airplane was partially disassembled, and transported to the pilot's hangar at PRC for further examination. PERSONNEL INFORMATIONAccording to Federal Aviation Administration (FAA) information, the pilot held a private pilot certificate with airplane single- and multi-engine ratings. His most recent FAA third-class medical certificate was issued in November 2011. According to the pilot, he had a total flight experience of about 2,500 hours, including about 40 hours in the accident airplane make and model. His most recent flight review was accomplished in September 2012. AIRCRAFT INFORMATIONFAA records indicated that the airplane the first model of its type, and was built by its principal designer, G.L. Siers. The airplane was first issued its airworthiness certificate in 1975. The design was a single-engine, low-wing monoplane constructed primarily of wood. It was equipped with hydraulically-operated tricycle-configuration landing gear, and a Lycoming IO-540 series engine. The accident pilot was the second owner of the airplane; he purchased it from the designer/builder in February 2007. According to the pilot, in July 2007, he "had the engine and prop rebuilt as they were both past TBO." In 2009 the airplane was damaged on landing due to a problem with the nose landing gear. The nose gear contacted a gear door while retracting; the pilot subsequently determined that the components intended to align the nose gear for retraction were of insufficient strength and had deformed, preventing normal nose gear operation. The pilot reported that the components "were repaired and reinforced." The airplane's most recent annual condition inspection was completed on October 27, 2011, exactly 1 year prior to the accident. Maintenance records indicated that at that time, the airplane had accumulated a total time (TT) in service of about 516 hours. The pilot reported that the airplane had flown "about 8 or 9 times" since that inspection, and that "there were no problems." METEOROLOGICAL INFORMATIONThe PAN 1635 automated weather observation included winds from 130 degrees at 8 knots, visibility 10 miles, clear skies, temperature 13 degrees C, dew point -8 degrees C, and an altimeter setting of 30.18 inches of mercury. AIRPORT INFORMATIONFAA records indicated that the airplane the first model of its type, and was built by its principal designer, G.L. Siers. The airplane was first issued its airworthiness certificate in 1975. The design was a single-engine, low-wing monoplane constructed primarily of wood. It was equipped with hydraulically-operated tricycle-configuration landing gear, and a Lycoming IO-540 series engine. The accident pilot was the second owner of the airplane; he purchased it from the designer/builder in February 2007. According to the pilot, in July 2007, he "had the engine and prop rebuilt as they were both past TBO." In 2009 the airplane was damaged on landing due to a problem with the nose landing gear. The nose gear contacted a gear door while retracting; the pilot subsequently determined that the components intended to align the nose gear for retraction were of insufficient strength and had deformed, preventing normal nose gear operation. The pilot reported that the components "were repaired and reinforced." The airplane's most recent annual condition inspection was completed on October 27, 2011, exactly 1 year prior to the accident. Maintenance records indicated that at that time, the airplane had accumulated a total time (TT) in service of about 516 hours. The pilot reported that the airplane had flown "about 8 or 9 times" since that inspection, and that "there were no problems." WRECKAGE AND IMPACT INFORMATIONSeveral days after the accident, and FAA inspector examined the wreckage in the pilot's hangar. The inspector reported that "both main gear had punctured through the tops of both wings," the landing gear doors were damaged, and that the "propeller was destroyed." The inspector did not note any obvious underlying reasons for the initial failure of the NLG. According to the pilot, the uncommanded retraction of the MLG was an expected result of the NLG failure, due to the system architecture.