Aviation has a rich and colorful past and, over the years, many people have made noteworthy contributions to help keep history alive. Not the least of the contributors have been those people working in conjunction with organizations, or on their own, to keep early aircraft in the air. With each passing year, it becomes more difficult and expensive to maintain and operate original surviving aircraft. Replicas, built from scratch or kits, provide an alternative way for us and future generations to still see rare birds in flight and allow our imaginations to return to the times of aviation's pioneers. Unfortunately, not all efforts to build and operate such replicas are successful, and the NTSB is called on to find out what went wrong.
An experimental amateur-built Fokker DR.1 triplane crashed two miles northeast of Parker, Colo., resulting in serious injuries to the ATP-rated pilot who was the only person on board. The weather was VFR for the planned flight from Centennial Airport (APA) in Englewood, Colo., to the Platte Valley Airpark in Fort Lupton, Colo. Weather at APA included clear sky, wind at seven knots, visibility 10 miles and temperature 77 degrees F.
FAA records showed that the airplane received takeoff clearance from the APA tower just after 9:40 a.m. About 2 1⁄2 minutes later, Denver Center radar showed that the airplane had reached 6,200 feet MSL, and it was positioned slightly east of the takeoff runway. The APA field elevation is 5,885 feet MSL. Radar showed the airplane made a left turn to approximately 95 degrees and had a ground speed of about 93 knots. The radar data showed the airplane gradually climbed to 6,700 feet, then entered a descending left turn at just after 9:46 a.m. The airplane struck the ground, which was at an elevation of 6,170 feet MSL.
A husband and wife heard the airplane heading toward their house, and went outside in time to see it pass overhead. They said it was yawing to the left and was a couple of hundred feet up.
The pilot required seven months of healing and physical therapy. He told investigators he couldn't recall any of the events of that day and said that the first thing he remembered after the accident was waking up in the hospital. The pilot had reported about 19,650 flight hours at the time: His FAA second class medical certificate was issued about six months before the accident. According to the airplane's owner, the pilot had about 150 hours in the accident airplane.
The airplane was a full-scale replica of a World War I German Fokker DR.1 triplane. It was painted red and marked to resemble the airplane flown and made famous by the Red Baron, ace German fighter pilot Baron Manfred Von Richtofen. The three-wing airplane had only one seat, was built in 1978, and had an airworthiness certificate in the experimental amateur-built category. Power was from a modern Lycoming IO-360-B4D fuel-injected engine rated at 180 hp at 2,800 rpm. At the accident site, the airplane's tachometer showed 638.38 hours.
The accident site was in a rolling pasture. The cowling and forward fuselage around the engine were broken and fragmented. The cockpit floor was crushed upward. The cockpit walls were bent and broken outward and down. The instrument panel was broken forward and fragmented. The windshield with replica machine guns was broken. The wings were broken, as was the fuselage aft of the cockpit. The empennage and tailwheel showed no damage. Control continuity was confirmed.
Examination of the engine failed to reveal any problems that would have resulted in the production of less than rated power. Tests on the 100LL fuel supply at APA showed no problems. About seven gallons of fuel had been put into the airplane before the accident.
Another pilot who flies World War I replica airplanes told investigators that the Fokker was designed to be highly maneuverable and was unstable. He said it was very pitch sensitive, that the ailerons were okay, and that the rudder was pretty powerful. He said the airplane climbs at about 65 mph and cruises about 105 mph. He said the airplane gives a warning before it stalls, but you have to get the nose pointed down quickly. He said he had flown the accident airplane at least three or four times.
The density altitude in the area was calculated to have been about 8,250 feet at the time of the accident. The airplane would have displayed decreased performance compared with operating at a lower density altitude. Calculations indicated the takeoff distance required to get airborne would have been more than double the requirement under standard conditions, and the airplane's rate of climb would have been decreased by 67%.
The NTSB determined that the probable cause of this accident was the pilot's loss of control of the airplane due to the airplane's reduced climb performance during high density altitude operations.
A replica Curtiss JN-4D struck power lines and crashed shortly after takeoff from the Owatonna Degner Regional Airport (OWA). The takeoff was made from grass in the direction of runway 30. The pilot was killed and the front-seat passenger received serious injuries. The airplane was substantially damaged. It was VFR at the time.
The passenger recalled nothing about the accident. He did remember that the pilot, who owned the airplane, contacted him on the morning of the accident and asked him to the get the airplane ready to fly. The passenger, who had helped build the airplane, got it out of the hangar and put in fuel. He said the pilot arrived at the airport and flew the Jenny once around the pattern. The pilot then asked him if he wanted to go for a ride. The passenger told investigators that he remembers getting into the airplane, but nothing more.
A witness said he saw the airplane lift off, then looked away, and looked back to see the airplane banked 80 degrees to the left and turning. He said it didn't appear to be climbing. He said it entered a steep nose-down attitude.
The pilot held a private pilot certificate. His third class medical certificate had expired. At the time of his last medical, about three years before the accident, he reporting having 3,400 total flight hours. No recent logbooks could be found. The airplane was a replica of a 1917 bi-wing Curtiss Jenny. An overhauled, 90 hp, liquid-cooled, Curtiss OX-5 engine powered the airplane. It was issued a Special Airworthiness Certificate along with Experimental Operating Limitations.
The passenger reported that he had worked with several other people to build the Jenny, and that it had been flown approximately five times prior to the accident. The passenger said the entire airplane was new with the exception of some nuts and bolts, and the engine which had just been overhauled. He said the engine had been running fine and, in his opinion, the airplane was underpowered for recovery from a stall at low altitude.
Another person who helped build the airplane reported it took approximately 10 years to complete. The airplane wasn't equipped with radios. Both the front and rear seats had flight controls, but all instrumentation was in the rear. The airplane was equipped with new seat belts, but no shoulder harnesses were installed.
The airplane's Experimental Operating Limitations contained a provision stating, "No person may be carried in this aircraft during flight unless that person is essential to the purpose of the flight."
The NTSB determined that the probable cause of this accident was the pilot's failure to maintain adequate airspeed during the takeoff climb, resulting in an inadvertent stall at low altitude.
A Wright Flyer experimental amateur-built airplane crashed during a forced landing near Springfield, Ohio. The two commercial pilots were killed. The local VFR flight originated from the Springfield-Beckley Municipal Airport (SGH). The replica followed the original Wright design using modern materials.
According to the owner, the airplane was undergoing initial flight testing. Witnesses said the airplane's engine sounded like its rpm varied. The airplane was seen flying slowly and banking to the left and right. One witness reported that the airplane spiraled downward.
The replica had modern airfoils, conventional ailerons, steel tube structure, and modern aircraft fabric. It was powered by a four-cylinder, 205 hp Lycoming HIO-360-C1B engine. It had two chain-driven counter-rotating two-blade pusher propellers. The airplane had two seats and dual controls. The airplane had accumulated 58 total flight hours.
The airplane had flown a racetrack pattern at about 3,100 feet, about three to four miles from the airport. Then, a pilot radioed that they were inbound for a touch-and-go. A subsequent radio call was an alert that they were landing in a field.
A video from an onboard camera showed that the airplane yawed to the left, as if thrust from the left propeller had been lost. This led investigators to discover that the left propeller shaft had completely separated at its aft weld. A magnified edge view of the tube separation revealed that approximately 25 to 35% of the through thickness of the propeller shaft tube hadn't been welded to the propeller shaft end. Visible defects, such as pores and voids, were observed.
The NTSB determined that the probable cause of this accident was the flight crew's failure to maintain airplane control following a partial loss of engine thrust during cruise flight. Contributing to the accident was the failed weld as a result of incomplete welding on the left propeller shaft, which led to the partial loss of engine thrust.