Backhoe loader drive system into their backhoe loaders, allowing these models to go over almost any terrain with little difficulty. Since the backhoe was invented, several companies such as Caterpillar and John Deere have changed the backhoe's back arm to be slightly curved like that of an excavator, which can allow more maneuverability. Backhoe loaders are very common and can be used for a wide variety of tasks: construction, small demolitions, light transportation of building materials, powering building equipment, digging holes/excavation, landscaping, breaking asphalt, and paving roads. Often, the backhoe bucket can also be replaced with powered attachments such as a breaker,
Rear flank downdraft tornadogenesis. Downdraft may have the following roles in near-ground mesocyclogenesis: Rear flank downdraft The rear flank downdraft or RFD is a region of dry air wrapping around the back of a mesocyclone in a supercell thunderstorm. These areas of descending air are thought to be essential in the production of many supercellular tornadoes. Large hail within the rear flank downdraft often shows up brightly as a hook on weather radar images, producing the characteristic "hook echo", which often indicates the presence of a tornado. The rear flank downdraft can arise owing to negative buoyancy, which can be generated by cold