On January 19, 2008, at an undetermined time after 1000 mountain standard time, an Air Creation Clipper, N614LF, descended into desert terrain during an undetermined phase of flight. The accident occurred about 8 miles northwest of Green Valley, Arizona. The experimental category light sport, weight shift control aircraft (trike), was substantially damaged. The sport flight instructor and the student pilot were killed. The trike was registered to the student pilot. The flight was performed under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed at the time of the instructional flight, and no flight plan was filed. The flight originated from the privately owned Ruby Star Airpark, Green Valley, at an undetermined time before 0900. No witnesses reported observing the accident. The pilots were reported overdue on the evening of January 19, and the wreckage was found the following day. The accident was originally reported to the National Transportation Safety Board as involving an ultralight vehicle. A Federal Aviation Administration (FAA) aircraft registration number was subsequently observed on the aircraft. The manager of the Ruby Star Airpark reported to the Safety Board investigator that on the morning of the accident, between 0900 and 1000, he had observed the accident trike flying in the vicinity, and nothing unusual was noted. The manager stated that the weather was "beautiful." The wind was calm, and it was sunny. The accident trike was based in a hangar at the airpark. The manager stated the trike's owner and his flight instructor had parked their automobiles at the airpark, so he believed they intended to return to the airpark following their flight. The manager observed a 5-gallon tank of fuel at the hangar. He opined that the pilot could have refueled his trike, if necessary. The 57-year-old flight instructor (pilot-in-command) held a private pilot certificate with a glider rating. In December 2005, the pilot was issued a repairman, experimental aircraft builder certificate. The certificate bore the following limits: "Inspection certificate for experimental aircraft [in the pilot's name], Model Air Creation...." The pilot's personal flight record logbook bore an endorsement, dated October 4, 2005, indicating he was proficient to act as pilot-in-command of weight shift control land light sport aircraft. In November 2007, the pilot was issued a flight instructor certificate, with a sport pilot limitation. No logbook evidence was found of the pilot having given any dual flight instruction as of the last logged entry, dated January 11, 2008. The pilot did not hold a FAA aviation medical certificate. The flight instructor's wife reported to the Safety Board investigator that her husband had completed the 5-hour Phase One flight test in the accident trike within 7 days preceding the accident. (Note, according to the trike's FAA operating limitations, 5 hours of flight testing is required to be completed with the pilot as the sole occupant prior to carrying a passenger/student.) The pilot's wife also indicated that the accident occurred during her husband's first introductory flight with the student. The student pilot did not hold any class of pilot certificate. No logbook or flying records were provided to the Safety Board investigator for examination. Family members reported that the student had purchased the accident trike in October or November 2007. He had flown the trike on about two occasions with an instructor. Reportedly, the student had not received any previous dual flight instruction. An FAA airworthiness inspector examined the terrain surrounding the accident site. A ground scar was observed confined to the area where the trike came to rest. No impact evidence was observed in the surrounding terrain. Native vegetation a few yards away from the wreckage appeared undisturbed. Based upon the absence of ground scar around the wreckage, and the deformation to the structure, the FAA inspector reported that the trike appeared to have descended into the ground while in a steep nose down attitude. The FAA inspector also examined the experimental weight shift control trike's engine assembly and broken airframe structure. According to the FAA inspector, evidence was found of fuel in the engine's carburetors and fuel delivery line. The propeller was rotated, and the engine's drive shaft turned freely. Several airframe components were found bent in an aft direction. For example, the right wing spar was broken in an aft direction approximately 3 feet from its tip. There was no evidence of the spar having flailed around during flight. The Air Creation distributor also examined the trike and the accident site. The distributor reported to the Safety Board investigator that the trike was equipped with a Rotax 582 engine and with "what appeared to be a Power Fin brand propeller." The propeller was not a model offered in the Air Creation design. An Air Creation model Kiss 13 square meter/400 kilogram wing was mounted on the trike's fuselage. The leading edge of the wing had several feet of duct tape covering cosmetic damage. The presence of the tape indicated that it was possible the trike had been involved in a previous mishap. All points of assembly were found intact, and all of the set-up bolts were present. The body of the trike's fuselage had been modified. The distributor additionally reported that the trike appeared to have crashed in a nose down attitude. Toxicology tests were performed on specimens from both pilots. No evidence of drugs or ethanol was found. The autopsies revealed both pilots were killed due to multiple blunt force traumatic injuries. The coroner noted that the flight instructor had evidence of ischemic heart disease, with severe coronary atherosclerosis and myocardial fibrosis.