A Cessna 208B EX Caravan that broke apart and crashed last month in Washington state was in the fourth day of testing to expand a drag-reduction system produced for the Caravan for the EX model. That’s according to a preliminary report released on Friday by the NTSB.
Two pilots and two staff members of Raisbeck Engineering died in the Nov. 18 crash. The company said at the time that the aircraft had not yet been modified.
On the first day of testing, according to the report, the first day of flight totaled 1.1 hours, consisting of a pilot familiarity flight and a ferry flight to test weight and balance. Data collection began in the following day’s two flights, totaling 4.6 hours to gather baseline data for both mid center-of-gravity cruise flight and forward center-of-gravity stall speeds.
Two test flights took place on the day before the crash with the accident test pilot and a different right-seated pilot on board. The first flight of 1.2 hours tested center of gravity static stability. The second flight, testing the plane’s aft center of gravity stall characteristics ended with about half of the test card completed because an aft crewmember felt ill.
The Cessna 208 took flight on Nov. 18 to complete the test card. Preliminary radar data shows the plane departed Renton, Washington just before 9:30 a.m., flying north. It climbed to 9,500 feet and began a series of turns and maneuvers for about 45 minutes at altitudes ranging between 6,500 feet and 10,275 feet.