Glenwood, FL, USA
N3YZ
LUTERS ARNIS V LEGEND
The amateur-built airplane was in cruise flight at 3,000 feet above ground level when it experienced a total loss of engine power. The pilot performed a forced landing to a field, and the airplane sustained substantial damage during the landing. Postaccident examination revealed that the fuel control unit (FCU) condition lever was 20 degrees out of its run position. Further examination of the condition lever revealed that the condition lever’s outer cable had been improperly installed, which allowed the uncommanded aft movement of the condition lever, which could result in a loss of engine power. A broken engine mount, which was likely the result of impact-related forces, was also found. This broken engine mount resulted in a slight turbine misalignment. When the turbine was realigned, the FCU condition lever settings were normal. The engine was subsequently started and operated normally with no irregular noises or hesitation. According to the engine manufacturer’s representative, if the condition lever had been installed properly, there should have been no such movement of the condition lever.
On June 27, 2012, at 1028 eastern daylight time, an experimental amateur-built Legend airplane, N3YZ, experienced a total loss of engine power at 3,000 above ground level (agl) in the vicinity of Glenwood, Florida. The airline transport pilot made a forced landing to a fern field and the airplane sustained substantial damage. The pilot was not injured. The airplane was registered to Aircraft Guaranty Corporation Trustee, and was operating as a 14 Code of Federal Regulations Part 91 personal flight. Instrument meteorological conditions prevailed and an instrument flight rules flight plan was filed. The flight originated from Deland Municipal Airport, Deland, Florida, at 1024, en route to Norfolk, Virginia. The pilot stated he was in cruise flight below the clouds, in contact with approach control, when the engine lost all power. He attempted a restart with negative results, looked for a suitable forced landing area, and made a "mayday" call to approach control. He selected a field away from a housing area and made a forced landing to the field. The pilot, age 50, held an airline transport pilot certificate with ratings for airplane single-engine land, airplane single-engine sea, airplane multiengine land, and instrument airplane. In addition he held a first-class medical certificate with the restriction, "must wear corrective lenses." The pilot had logged 14,700 hours in all aircraft and 3 hours in the same make and model as the accident airplane. He had flown 91 hours in all aircraft in the last 90 days; of which, 3 hours were in the same make and model as the accident airplane. He had flown 16 hours in the last 30 days in all aircraft of which 16 hours had been in single engine airplanes. The pilot's last flight review was in the legend on May 27, 2012. The Legend is a single-seat amateur built airplane with a tricycle landing gear, serial number 2024 was built in 2005. The airplane was powered by Walter M601D 721 turbo prop horsepower engine. The last condition inspection was conducted on March 27, 2012 and the total airframe hours at time of the inspection was 177.2. The airplane had flown 4 hours since the engine was overhauled. According to the previous owner, he had not experienced any problems with the engine shutting down before the condition lever was placed in the detent position. Post accident examination of the airplane by a Federal Aviation Administration (FAA) inspector revealed it came to rest in the middle of a fern field of the top of black tarps used to shade the fern crops. The tarps were suspended with 1.5 inch rebar and .25 inch steel cables. The airplane became entangled in the wires and tarps, which stopped it. The impact tore apart several areas of the airplane, including the wings, empennage, and control surfaces of the tail. The fuselage remained intact with some cracking on the right side at the wing attachment point. The nose landing gear and the main landing gear were in the retracted position. The cockpit remained intact and the canopy opened and shut normally. According to the FAA inspector, the condition lever control knob quadrant was not sturdy and had lateral movement when actuated by hand. The pilot stated he turned the condition lever off prior to exiting the airplane. When actuated, it was hard to determine were the detent for the flight idle position was located. Also, the distance in travel from the off position to the idle and run detent was small, making it difficult to determine where the detent was. The condition lever to fuel control unit (FCU) was 20 degrees positive to the run position. This was due to a broken engine mounting that caused the turbine to be out of alignment. The turbine was positioned into its original position and all settings were found to be normal. On further inspection, it was found that if the turbine power was reduced and zero to negative G's experienced, the condition lever on the FCU would move to the aft position and result in a possible flame out. The condition lever under power did not need to travel fully aft to shut the turbine down. The right wing remained attached at the wing root. The leading edge of the wing was separated at the fuselage attachment point. The right aileron remained attached at all hinge points and the right flap remained attached at all hinge points and was not extended. The right main fuel tank was ruptured and no fuel was present. The elevator and vertical fin were separated at the attachment point of the empennage when it collided with a high tension wire. Minor damage was sustained to the control surfaces and continuity of the rudder and elevators was confirmed forward to the initial separation point. The Left wing was broken open at the leading edge in three places, going back to the wing spar. The left aileron and flaps remain intact. The left main and auxiliary fuel tanks were breached and had no fuel remaining. All propeller blades remained attached to the propeller hub and were bent. The propeller spinner remained attached and was damaged. The propeller turned freely by hand. Examination of the engine was conducted at a salvage yard. Visual examination revealed no immediate sign or indication of malfunction. All controls, tubing, and electrical wiring were found connected. The left rubber section of the engine mount was broken, but the engine remained aligned with frame. A bore scope was used to inspect the power and compressor blade sections for any visible damage and no anomalies were noted. Straps were attached to the power turbine and a forklift. The power turbine was inspected and no damage was noted. The straps were removed from the power turbine and the forklift, and the power turbine and planetary gear turned freely. The drive on the accessory case was turned. The center section with the compressor and centrifugal turned freely indicating. The compressor was inspected and no anomalies were noted. The electro hydraulic transducer was checked to ensure it was not active out of the start sequence. The electric fuel pump was connected to a fuel supply. A clear container was used with a clear bleed pipe. Fuel was siphoned out of the container fitting on the bleed pipe, one at a time, to the four bleed points on the FCU. No air or contaminated fuel was found in the FCU. Data was downloaded from the turbine start limiting management system and no exceedances were noted. The Environmental Protection Agency (EPA) pipe from the FCU drain to the EPA can was removed and checked. No anomalies were noted. The isolation valve in the cockpit was checked and was in the off position. The engine manufacture stated, "It is non standard to mount the outer cable to the non moving engine mount mounted to the turbine itself. In this case if it had the standard installation even with broken engine mount there would have been no movement to the condition lever positive or negative." Examination of the condition lever revealed an improper installation of the outer cable, which allowed the condition lever to move to the aft position, causing engine flame out. Examination of the airframe and flight controls revealed no additional anomalies. The engine was subsequently started and normally and ran with no irregular noises or hesitation. The engine was started and the turbine start was normal with no irregular noises or hesitation. The return line from the pressure header tank was removed and the fuel pump was turned on and the fuel flowed freely. The header tank was removed and the fuel was drained into a clear container. No anomalies were noted. The screw on the filter from the header tank was removed and drained into a glass jar. No water or contaminated fuel was noted. All turbine and fuel line were checked and no anomalies were noted.
The total loss of engine power due to the airplane builder’s improper installation of the fuel control unit condition lever cables, which resulted in the airplane’s subsequent forced landing.
Source: NTSB Aviation Accident Database
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