Superior Air Parts settles fatal crash suit for $5 million

Fatigue failure of the crankshaft on a 215-horsepower Superior XP-400 engine that had been recently installed on the aircraft contributed to the accident, said the National Transportation Safety Board, which gave the probable accident cause as a “stall and loss of control” as the pilot maneuvered for a forced landing.

Dane Sheahen, a private pilot with approximately 880 hours who built the airplane, and his passenger James Kos, an airframe and powerplant mechanic and 25-hour student pilot, were killed in the accident.  The two-place tandem airplane crashed near Clermont, Florida, on a personal flight from Spruce Creek Airport in Port Orange to Winter Haven Regional Airport, according to the NTSB report. The report included the account of a witness observing the aircraft in a noiseless, nose-low descent, “consistent with an aerodynamic stall.”

Based on logbook entries and electronic data, “the estimated total engine time since installation was about 20 hours,” the report said.

In a February 10 news release issued by a public relations firm, the law firms Slack Davis Sanger and LaRose and Bosco noted that the experimental aircraft engine developed by Superior Air Parts was equipped with a crankshaft forged by Ruhrtaler Gesenkschmiede F.W. Wengeler GmbH & Co. KG.

However, “There were no obvious metallurgical deficiencies in the crankshaft, therefore the failure was probably the result of detonation issues and unusual stresses caused by the Superior design,” said attorney Ladd Sanger.

“Superior Air Parts failed to adequately test the engine design before releasing it to the market. Once in the field, Superior knew these engines were suffering premature failures yet the company was slow to react until this tragic crash occurred,” Sanger added.

A Superior Air Parts spokesman told AOPA the company would not comment on the settlement.

In March 2019, AOPA reported that Coppell, Texas-based Superior Air Parts had begun an immediate, mandatory buyback of its XP-382 and XP-400 engines, which shared some components, because of the possibility of detonation-induced damage.