Tie
While those trees look small in the photo, they are at least a foot, and closer to two feet in diameter, and there are several. By the way they look at the base, they were sheared off at ground level by the cab/trailer sliding into them. Then with their position in the photo, the impact threw the bases at least 30-40 feet away. It takes quite a lick to do that. And it will do quite a bit of damage to what ever hits it. By the looks of the trees and cab, he impacted the trees directly with the cab, while it was sliding on its side. The reason for that is the minimal damage to the front of the tractor. It impacted the cab right above the front bumper. Very little protection for the driver in an accident like this. Fiberglass, while strong, is not a match for a tree when it comes to an impact.
On a related note, we had a trash truck back into one of our p1000's several years ago. THe driver was in the seat doing paperwork. Trash truck was doing less than 5 MPH in reverse. It crushed the cab of the p1000 so badly, they had to cut him out of the cab. Another couple inches, and he would not have survived. And that was at less than 5MPH.
Package cars and tractors really have little protection for the driver in a wreck.
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