N29TMMontague Thomas W LONG EZ · 1987

On August 19, 2023, about 0820 eastern daylight time, a Rutan Long EZ, N29TM, was substantially damaged when it was involved in an accident near Genoa Township, Michigan. The pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

According to the pilot, he was cleared to climb the airplane to 8,000 ft mean sea level (msl) after takeoff. At 4,850 ft msl the engine suddenly lost power. The pilot reported the loss of engine power to air traffic control and was given vectors to the nearest airport. The pilot could hear the propeller windmilling and attempted to restore engine power by adjusting the fuel mixture, switching fuel tanks, turning on the electric fuel boost pump, and cycling the ignition switch from BOTH to OFF and then cycling through LEFT, RIGHT, and back to BOTH. The pilot also engaged the starter in an attempt restore engine power. All attempts to restore engine power were unsuccessful. The pilot reported to air traffic control that he would not be able to make the airport and chose to ditch the airplane into a pond. During the ditching attempt, the airplane struck a tree and impacted the water which resulted in substantial damage to both wings and the fuselage.

The airplane was recovered and examined several days after the accident. Engine control continuity was established from the cockpit to the engine. A pair of Nomex flight gloves were found on top of the No. 2 cylinder; the owner stated that they belonged to him, and he did not know how they got there. The top spark plugs were removed and were light gray/brown in color. Thumb compression and suction was verified on all cylinders. The valve covers were removed and valvetrain continuity was established when the propeller was rotated by hand.

Borescope examination of the cylinders was performed about nine months after the accident. The cylinders all displayed corrosion and scoring. The valves were intact and opened and closed during propeller rotation.

The engine had been converted from a carbureted system to a fuel injection system. The fuel injection system appeared to be intact; however, it could not be tested due to the condition of the engine. The airplane’s electrical grounding was checked with no anomalies found.

The airplane was equipped with dual E-Mag electronic magnetos. Both magnetos contained internal alternators capable of powering the ignition system in the event of the loss of airplane electrical power. Both magnetos functioned normally when tested. Each magneto had a thermal indication sticker designed to change colors at temperatures above 200°F. Each magneto’s thermal sticker had turned to a dark gray color. According to the magneto manufacturer, temperatures must reach 235 – 245°F to turn the sticker dark gray to solid black. In addition, the magneto manufacturer stated that high operating temperatures primarily affect long term degradation of components and do not, except in extreme conditions, result in sudden failure.

The E Mag Installation and Operating Guide (LC114.28) stated that installation of magneto blast tube cooling should be considered mandatory for installed E Mags. Air blast (cooling) tubes help to reduce the ignition operating temperatures. LC114.28 also stated that, “ignitions operating at exceptionally high temperatures can experience thermal shut down.” The airplane had blast tubing installed to each magneto; however, the effectiveness of the blast tubing as installed could not be determined. The guide stated that, “the mere presence of blast-tubes does not guarantee they are operable and/or effective.”