Cab over

Cab-over, also known as Cab Over Engine (COE), cab forward (U.S. English), or forward control (British English), is a body style of truck, bus, or van that has a vertical front or "flat face", with the cab of the truck sitting above (or forward of) the front axle. This contrasts with a conventional truck where the engine is mounted in front of the driver.

This truck configuration is currently common among European and Japanese truck manufacturers, because the laws governing overall vehicle lengths are strict and the body style allows longer trailers (in the case of a tractor-trailer truck) or a longer cargo area (in the case of a "straight" truck, a truck with a single rigid frame supporting all components and the load) for the same overall length.

Although popular among United States heavy truckers and trucking companies during the 1970s because of strict length laws in many states, when those length laws were repealed, most heavy-truck makers moved to other body styles. It is, however, still very popular in the light- and medium-duty truck segment. However American companies Kenworth and Freightliner still manufacture traditional cab over engine designs for the Australasian and South African markets where length restrictions still make them advantageous.

Cab forward

The term cab forward refers to various rail and road vehicle designs that place the driver's compartment substantially farther towards the front than is common practice.

Rail locomotives

In steam locomotive design, a cab forward design will typically have the driver's compartment (or cab) placed forward of the boiler at the very front of the engine. On a coal-fired locomotive, the fireman's station remains on the footplate behind the firebox so as to be next to the tender. On an oil-fired locomotive, the fireman's station could be (and normally is) in the forward cab. This type of design was widely, though not commonly, used throughout Europe in the first half of the 20th century, often in conjunction with an enclosed body design and/or streamlining.

Visibility is greatly improved from the cab, and fumes from the chimney do not fill a forward cab in tunnels. However, the crew's prospects in the event of a collision are worse, and if the driver and fireman are in separate places it is difficult for them to communicate, just as in autotrains.