Right now, the maximum length for truck trailers is 53 feet. A new transportation bill would extend that to allow double trailers.
A semi - trailer (British English) or semitrailer (American English) is a trailer without a front axle. A road tractor coupled to a semi - trailer is often called a semi - trailer truck or " semi " in North America & Australia, and A B- double consists of a prime mover towing two semi - trailers, where the first semi - trailer is connected to the Properties · Couplings · Types · See also.
Showing what they don't teach you in truck driving school!.