History of Flight
On November 5, 2008, at 0945 central standard time, a Johnson Cozy MK-IV experimental airplane, registration N637PS, was destroyed when it struck a power pole during a forced landing at Osceola Municipal Airport (3MO), Osceola, Missouri. The airplane experienced a loss of engine power during a cross-country flight. Visual meteorological conditions prevailed. The personal flight was conducted under 14 CFR Part 91 without a flight plan. The pilot was seriously injured. The cross-country flight originated at St. Charles Airport (3SQ), St. Charles, Missouri, and was en route to Tradewind Airport (TDW), Amarillo, Texas.
The pilot had just completed a multi-day cross-country flight from California to Kitty Hawk, North Carolina, using a biofuel called N-butanol. The purpose was to demonstrate the viability of flight using an alternative fuel to aviation gasoline (AVGAS). After completing the demonstration, the pilot was returning to California, having refueled twice with AVGAS. While cruising at 6,500 feet mean sea level (MSL), the airplane engine overheated and then quit producing power. The pilot reported that the engine began running rough as exhaust gas temperatures (EGT) reached 490 degrees. A slow power loss occurred as EGT reached 570 degrees. The pilot performed a forced landing on an unimproved grassy area at 3MO. The airplane struck a power pole, crossed a paved road, and struck a second power pole.
The pilot stated that while performing the before-landing checklist, when he elected to deploy the landing brake, the electric landing brake switch was already in the deploy position and the landing brake enunciator light was illuminated. He thought he had inadvertently deployed the brake earlier, while manipulating controls in turbulence and wearing bulky cold-weather gloves, prior to the overheat condition.
Personnel Information
The pilot, age 55, held a private pilot certificate with a rating for airplane single-engine land. His last FAA third-class medical was issued July 1, 2008, with the limitation "Must Wear Contact Lenses." He reported 378.6 total flight hours and 30 hours in the preceding three months.
Aircraft Information
The 2000-model Leonard Johnson Cozy MK-IV, serial number 287, was a mid-wing airplane with fixed main landing gear, retractable nose gear, and configured for one occupant. It was powered by a direct-drive, carbureted, air-cooled, six-cylinder reciprocating engine (Lycoming O-360-A2G, 180 horsepower) driving a two-bladed propeller in a pusher configuration.
The airplane was built with an electric landing brake system, using an electric switch for activation and an electric motor for actuation. An orange enunciator light on the center instrument panel provided visual alert when the landing brake was deployed. The original design called for a mechanical system with a lever for deployment and retraction, which also provided visual indication.
According to the pilot, the airplane had experienced an overheat condition on cylinder number three on October 30, 2008, attributed to a cracked helicoil in the spark plug hole. The cylinder was replaced and the engine operated normally until the accident.
The last airplane inspection was a Conditional inspection on April 3, 2008. The airplane had accumulated 119.4 total hours, and the engine had 36.1 hours since overhaul and 13.4 hours since last inspection.
Wreckage and Impact Information
The pilot landed on a grassy unimproved area on the airfield. The airplane traveled several hundred feet and impacted a power pole, then crossed a paved road, impacted a second power pole, and came to rest inverted. Both wings and a portion of the nose separated. Both wings were fractured into multiple pieces.
Tests and Research
One designer of the Cozy MK-IV airplane stated in an interview that some builders installed an electrical controller for the landing brake as a modification. The use of an electrical LB system was not recommended or part of the original design. The electrical controller could prevent the LB from blowing back if deployed above 85 KIAS. The location of the LB activation switch could prevent timely retraction in a go-around.
The Cozy MK-IV builder and operators manual stated: "LANDING AIRBRAKE – A drag device used to allow a steeper approach and to provide more deceleration in the flare. This belly-mounted 'speed brake' is deployed by a lever on the center console. It is extended on downwind after gear extension and left down until after landing. Maximum speed with the airbrake down is 85 knots (100 mph). Above this speed, the brake automatically closes." The manual also noted that the awkward position of the brake handle in the deployed position aids in reminding the pilot that the brake is down, and climbs should be avoided with the brake down as cooling and climb rate are reduced.