Recalls All 4300 And 4700 Series Slick Magneto Distributor Gears With Copper Electrodes

On November 12, 2018, Champion Aerospace released a revised version of Slick Service Bulletin SB1-15 (entitled SB1-15A) recalling all 4300 and 4700 series Slick magneto distributor gears it manufactured with copper electrodes over eight years from September 26, 2008, through September 1, 2016. Champion identified a condition in distributor gears causing loosening of the copper electrode.

The release comes just 11 days after the deposition of Champion's president was taken in a product liability lawsuit alleging that a defective distributor gear in a Champion Slick 4370 magneto caused a 2015 accident that fatally injured two men. The consolidated lawsuits are pending in State Court in San Diego County under the master case entitled Carolyn Sarrisin, et al. v. Volar Corporation, et al., Case No. 37-2016-00019527-CU-PO-CTL. Flight instructor, Robert Sarrisin and student pilot, Jeffrey Johnson, were both fatally injured in the crash.

According to the NTSB's probable cause report, the flight instructor and student pilot were conducting touch-and-go takeoffs and landings in the airport traffic pattern. While on the upwind leg of the traffic pattern following the second takeoff, the airplane entered a steep left turn and impacted a residential area; a postimpact fire ensued. One witness reported that he heard the airplane's engine "shut off," and stated that it sounded as though the engine was "trying to restart."

Investigators could not determine who was manipulating the flight controls at the time of the accident. Examination of the airframe and flight controls revealed no mechanical anomalies that would have precluded normal operation.

The engine examination revealed no internal mechanical anomalies that would have precluded normal operation. The left magneto was not located. A teardown of the right magneto revealed that the internal components had been improperly assembled; the distributor gear electrode was not seated properly, and the distributor drive gear was stuck inside the magneto. Given the improper assembly of the right magneto it is likely that the magneto had failed to operate properly, which subsequently resulted in a rough running engine and a partial loss of engine power. It is likely that the flight instructor and student were distracted by the partial loss of engine power, and during the turn toward the open field, lost aircraft control and stalled the airplane, and subsequently hit flat terrain.

The probable cause for the accident, which is not admissible as evidence in court, was determined to be the pilots' failure to maintain airplane control following a partial loss of engine power after takeoff, which resulted in an aerodynamic stall. Contributing to the accident was the partial loss of engine power due to a failure of the right magneto.

The original release of the service bulletin (entitled SB1-15) on July 2, 2015, was limited to only those 4300 and 4700 Series Slick magneto distributor gears manufactured from November 1, 2013, through July 10, 2014. Champion had received reports of alleged defective magnetos with loose distributor gear electrodes that fell outside the 2015 service bulletin serial number range before the bulletin was issued. Champion ultimately changed the distributor gear electrode from copper to Monel in August 2016 but did not issue a new service bulletin until November 2018.

Although there is evidence that loose copper electrodes in these distributor gears can cause a loss of engine power, Champion has not warned the public of that risk, according to the lawsuit. Attorneys representing the plaintiffs in the case urge owners, mechanics, distributors and aviation parts stores to review the revised service bulletin and check their engines and inventory.

(Source: Law Offices of Robert Vaage. Image from file. Not accident airplane)

FMI: www.vaagelaw.com