NTSB Questions Pilot's Prescription Drug Use In Fatal Tulsa Plane Crash

The National Transportation Safety Board is questioning the prescription drug use of the pilot who was a flying a plane that crashed in 2010, killing him and his two passengers.

The crash killed Chase Bales, 51; Mats Malmberg, 43; and  Damian Riddoch, 37. All three men were executives with US Highland, a new motorcycle manufacturer in Tulsa.

7/10/2010: Related Story: Victims Identified In Fatal Saturday Night Tulsa Plane Crash

The twin-engine Cessna 421 crashed at 10:05 p.m. on July 10, 2010 in Mohawk Park north of Tulsa International Airport.

According to the NTSB's newly-released Factual Report on the crash, Bales had two prescription drugs and an over-the-counter drug in his system which are not approved by the Federal Aviation Administration for use by pilots.

Read the Factual Report.

The NTSB says Bales had Cyclobenzaprine in his blood and urine. Cyclobenzaprine is a muscle relaxant that carries this warning: "may impair mental and/or physical ability required for the performance of potentially hazardous tasks," according to the report.

According the NTSB, Bales also had Phentermine in his urine. The drug is used to aid weight loss and is a stimulant chemically similar to amphetamine.

The report also says Bales had Benadryl in his blood and urine. 

According to the NTSB, the three men had left Jones Riverside airport at 9:19 that morning for a business trip to Pontiac, Michigan. Before departing Pontiac for the return flight to Jones Riverside, the report says the pilot had fuel added to the plane.

A ground crewman reported a problem with a seal on the right main tank which allowed five or six gallons of fuel to drain from the tank. The crewman told the NTSB the spilled fuel was not replaced in the tank. 

At 9:47:53 p.m., the pilot checked in with Tulsa Approach Control and was cleared to Jones Riverside. But at 9:57:50 the pilot told controllers he'd like to land at Tulsa International Airport instead, and was directed to runway 18R. 

At 10:01:56 p.m. the pilot was given clearance to land, but at 10:02:23 the pilot stated "Tulsa, we've exhausted our fuel."

Controllers saw the plane descend into the woods north of the airport and then saw a flash.

The NTSB says the pilot did not inform any of the controllers on the ground that he had a fuel problem prior to reporting fuel exhaustion. 

Investigators say they found no problems with either engine that would have prevented normal operation.

The Factual Report is the NTSB's second of three reports on the crash. The last one will be the Probable Cause report which will most likely take a few more months to complete.