MANKATO — The National Transportation Safety Board said a pilot smoked marijuana within two hours before he crashed in west-central Minnesota nearly two years ago, killing himself and his brother.

According to a press release,  the accident report also says the experimental plane was significantly overloaded.

The plane, piloted by 52-year-old Mark Schultz, of Sleepy Eye, crashed shortly after takeoff from the Montevideo airport Sept. 7, 2014. The crash killed him and his brother, 51-year-old Steven Schultz of Brooklyn Center.

The NTSB report blames the crash on “the pilot’s impaired judgment due to the use of marijuana.” It said that led to his “improper decision” to fly the overloaded airplane and his subsequent loss of control while taking off in gusty winds.

There was no indication of any mechanical malfunction.