The trucking industry has made a large historical impact since the early 20th century. It has affected the U.S. bothpoliticallyas well aseconomicallysince the notion has begun.Previous to the invention of automobiles, most freightwas moved bytrain or horse-drawn carriage. Trucks were firstexclusivelyused by the military during World War I.
After the war, construction of paved roads increased. As a result, trucking began to achieve significant popularity by the 1930's.Soon after trucking became subject to various government regulation, such as the hours of service.During the later 1950's and 1960's, trucking accelerated due to the construction of the Interstate Highway System.The Interstate Highway System is an extensive network of freeways linking major cities cross country.
Trailer stability can be defined as the tendency of a trailer to dissipate side-to-side motion. The initial motion may be caused by aerodynamic forces, such as from a cross wind or a passing vehicle. One common criterion for stability is the center of mass location with respect to the wheels, which can usually be detected by tongue weight. If the center of mass of the trailer is behind its wheels, therefore having a negative tongue weight, the trailer will likely be unstable. Another parameter which is less commonly a factor is the trailer moment of inertia. Even if the center of mass is forward of the wheels, a trailer with a long load, and thus large moment of inertia, may be unstable.
The year of 1977 marked the release of the infamous Smokey and the Bandit.It went on to be the third highest grossing film that year, following tough competitors like Star Wars and Close Encounters of the Third Kind.Burt Reynolds plays the protagonist, or "The Bandit", who escorts "The Snowman"in order todeliver bootleg beer.Reynolds once stated he envisioned trucking as a "hedonistic joyrideentirelydevoid from economic reality"
Another action film in 1977 also focused on truck drivers, as was the trend it seems. Breaker! Breaker! starring infamous Chuck Norris also focused on truck drivers. They were also displaying movie posters with the catch phrase "... he's got a CB radio and a hundred friends whojustmight get mad!"
The most basic purpose of a trailer jack is to lift the trailer to a height that allows the trailer to hitch or unhitch to and from the towing vehicle. Trailer jacks may alsobe usedfor the leveling of the trailer during storage. To list a few common types of trailer jacks are A-frame jacks, swivel jacks, and drop-leg jacks. Other trailers, such as horse trailers, have a built-in jack at the tongue for this purpose.
In order toload or unloadbotsand other cargo to and from a trailer, trailer winchesare designedfor this purpose. They consist of a ratchet mechanism and cable. The handle on the ratchet mechanism is then turned to tighten or loosen the tension on the winch cable. Trailer winches vary, some are manual while othersare motorized. Trailer winches are mosttypicallyfound on the front of the trailer by towing an A-frame.