instance_of u engine
A ___MASK64___ or engine is a rail transport ___MASK32___ that provides the motive power for a train . The word originates from the Latin " loco "  " from a place ", ablative of " locus ", " place " + Medieval Latin " motivus ", " causing ___MASK40___ ", and is a shortened form of the term " ___MASK64___ engine ", first used in the early 19th century to distinguish between mobile and stationary steam engines . The straight or ___MASK12___ is an internal - combustion engine with all cylinders aligned in one row and having no offset . Usually found in four , six and eight cylinder configurations , they have been used in automobiles , locomotives and aircraft , although the term in - line has a broader meaning when applied to aircraft engines , see ___MASK12___ ( aviation ). An ___MASK82___ is the component of the propulsion ___MASK43___ for an aircraft that generates mechanical power . Aircraft engines are almost always either lightweight piston engines or ___MASK95___ turbines , except for small multicopter UAVs which are almost always electric aircraft . ___MASK23___ is an engineering term for the layout of the major components of a reciprocating piston internal combustion engine . These components are the cylinders and crankshafts in particular but also , sometimes , the camshaft ( s ). A U ___MASK85___ is a piston ___MASK85___ made up of two separate straight engines ( complete with separate crankshafts ) joined by gears or chains . It is similar to the H ___MASK85___ which couples two flat engines . The design is also sometimes described as a `` twin bank '' or `` double bank '' ___MASK85___ , although these terms are sometimes used also to describe V engines . This configuration is uncommon , as it is heavier than a V design . The main interest in this design is its ability to share common parts with straight engines . However , V engines with offset banks can also share straight ___MASK85___ parts ( except for the crankshaft ) , and this is therefore a far more common design today when both ___MASK85___ forms are produced from the same basic design . An H ___MASK85___ ( or H - block ) is an ___MASK23___ in which the cylinders are aligned so that if viewed from the front , they appear to be in a vertical or horizontal letter H . An ___MASK52___ is a ___MASK75___ that is able to fly by gaining support from the air . It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil , or in a few cases the downward thrust from jet engines . H ( named " aitch " or also " haitch " plural " aitches " or " haitches ") is the eighth ___MASK25___ in the ISO basic Latin alphabet . A ___MASK80___ ( archaically also omnibus , multibus , motorbus , autobus ) is a ___MASK19___ ___MASK32___ designed to carry many passengers . Buses can have a capacity as high as 300 passengers . The most common type of ___MASK80___ is the ___MASK6___ - decker rigid ___MASK80___ , with larger loads carried by double - decker and articulated buses , and smaller loads carried by midibuses and minibuses ; coaches are used for longer - distance services . Many types of buses , such as city transit buses and inter - city coaches , charge a fare . Other types , such as elementary or ___MASK46___ buses or shuttle buses within a post - secondary education campus do not charge a fare . In many jurisdictions , ___MASK80___ drivers require a special licence above and beyond a regular driver ' s licence .