Incident Overview
A pilot conducted a precautionary landing on a two-lane highway, after which he added oil to the airplane's engine. Subsequently, he attempted to take off from the highway. Local police provided vehicle traffic control and blocked off the section of highway that the pilot estimated he would need for the takeoff.
Takeoff Attempt and Collision
According to the pilot's report, during the takeoff roll he was reaching takeoff speed when he realized he would not become airborne in time to clear a police vehicle. He altered the takeoff ground roll to the right in an effort to avoid the vehicle. The right wing of the airplane impacted a highway sign. The airplane then continued off the highway to the right and down an embankment.
Aftermath and Damage
The airplane nosed over and came to rest inverted. The accident resulted in structural damage to the wings and the vertical stabilizer. The pilot reported that there were no mechanical anomalies with the airplane or its engine during the takeoff attempt.
Findings
No stated probable cause was provided in the source. The pilot indicated that the airplane and engine operated normally, and the collision occurred after evasive action to avoid a police vehicle.