WPR23LA198

The flight instructor reported that he and the pilot receiving instruction were conducting a series of touch-and-go landings and, while on the crosswind leg about 300 ft above ground level, the airplane stopped climbing and began to descend. The flight instructor stated there was not enough time to assess the engine or flight controls and he initiated a landing in a nearby field. During the landing roll, the right main landing gear collapsed, which resulted in substantial damage to the right wing. Both propeller blade tips were bent aft and exhibited some twisting. An examination of the airframe and engine found the right aileron cables were installed incorrectly and twisted, but any mechanical interference resulting from this was slight and likely imperceivable during preflight checks or inflight. A mechanic stated the magnetos were timed to 0°, and the engine technical specifications called for the magnetos to be timed 30°, which would have likely had a significant effect on the engine’s ability to produce power. However, the method in which the timing was checked was not established and it is unlikely the engine would have performed adequately for the airplane to have operated without the pilots recognizing there was an engine performance issue. Weather conditions at the time of the accident were conducive to serious icing at cruise power. It is possible the engine exhibited at least a partial loss of engine power due to carburetor icing, but neither pilot recalled a change in engine performance and a loss of engine power was not confirmed beforeto the accident. The reason the airplane descended uncontrollably could not be determined based on the available evidence.

On May 20, 2023, at 0820 mountain daylight time, a Silvaire Luscombe 8A, N71983, was substantially damaged when it was involved in an accident near Clovis, New Mexico. The flight instructor and the pilot receiving instruction were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. The fight instructor reported that they were conducting a series of touch-and-go landings at the Clovis Municipal Airport (CVN), Clovis, New Mexico. While on the crosswind leg for runway 04, about 300 ft above ground level, the airplane stopped climbing and entered a descending left turn. The flight instructor stated that rolling to the right seemed to create an out-of-trim condition that increased the rate of descent. The flight instructor stated there was not enough time to assess the engine or flight controls before he initiated a landing in a nearby field. Neither pilot reported hearing a change in engine noise or feeling any vibrations. During the landing roll, the right main landing gear collapsed, which resulted in substantial damage to the right wing. Both propeller blade tips were bent aft and exhibited some twisting. FAA inspectors conducted two examinations of the wreckage and a mechanic also conducted an independent postaccident examination of the airplane. The FAA inspectors reported finding no significant anomalies with the airframe, flight controls, or engine. The mechanic found that the right aileron cables were installed incorrectly and twisted, but stated any mechanical interference resulting from this was slight and likely imperceivable during preflight checks or inflight. No wear was found on the cables from the mechanical interference. No additional anomalies were noted with the flight control system. The mechanic reported both magnetos were timed to 0° before top dead center (BTDC). According to the Continental Engines engine specifications, the correct magneto timing is 30° before top center (BTC). The method in which the mechanic used to check the timing was not known. No other anomalies were found during examination of the engine. The pilot told the FAA inspectors that both magnetos operated normally during engine start and taxi, and the engine rpm dropped and increased when switched off and on. According to FAA Special Airworthiness Information Bulletin (SAIB) CE-09-35, Carburetor Icing Prevention, the weather conditions at the time of the accident were conducive to serious icing at cruise power.