BATH TWP., Mich. (WILX) - An experienced test pilot did not conduct the stall test flight that led to a deadly plane crash in Bath Township last month, according to a preliminary report from the National Transportation Safety Board.

The NTSB on Thursday released the findings of its preliminary investigation into the Oct. 16 crash that happened during a post-maintenance stall test flight, killing two pilots and a mechanic, all from Mexico.

The report, released Thursday, revealed the plane’s primary pilots conducted the stall test flight — not an experienced test pilot.

The Raytheon Hawker 800XP airplane arrived at Duncan Aviation’s maintenance facility at Battle Creek Executive Airport in March 2025 to undergo routine maintenance. Multiple routine inspections were completed on the airplane over the course of seven months.

One inspection included the removal of the wing leading edges and TKS ice protection panels for a visual inspection for cracks and signs of corrosion. Per the manufacturer, after the leading edge inspection, a post-maintenance stall test flight is required before the airplane can be returned to service.

Duncan Aviation officials said the flight crew was the primary crew for the plane that crashed and they flew that airplane about 150 hours per year, according to the report.

“Duncan Aviation personnel also reported that just prior to the completion of the maintenance procedures, the captain was provided with a list of experienced test pilots, for hire, to perform the postmaintenance stall test flight,” the report said. “However, after being unable to coordinate the stall test flight with a test pilot, the flight crew elected to perform the post-maintenance stall test themselves.”

The report says personal flight logbooks show the captain and co-pilot exclusively flew the accident airplane, and they completed their most recent training at a commercial simulator training facility in May 2025, about five months before the crash.

Thursday report also includes details about the flight crews’ last communications with air traffic controllers.

“At 1727 the airplane began a rapid descent from FL140, during which time there was an indiscernible transmission from the accident airplane, ATC responded ‘XA-JMR Cleveland,’ the report said. ”The flight crew responded, ‘we are in a...’ followed by a transmission in Spanish which translated to ‘in a stall, recovering, sorry.’“