- A term applicable to turboprop and turboshaft engines. A flat-rated engine’s thrust remains practically constant during an increase in altitude up to a certain limit. A method of referring to the engine-rated thrust or engine-rated shaft horse-power (SHP) that is guaranteed to be available up to a specific ambient temperature. The term flat rating is so called because of the flat nature of thrust versus the ambient temperature curve. The curve shows that from the lowest operating temperature possible to the specified temperature, the engine produces full thrust. Above this temperature, full thrust will not be permitted. At lower altitudes, the restricting factor is the torque that the airframe can withstand, and at higher altitudes, the exhaust temperature is the limiting factor. Flat-rated thrust also applies to power settings, such as maximum continuous, maximum climb, and maximum cruise, when the manufacturer would have to specify the thrust, ambient temperature, and altitude. Also called a re-rated engine.
Aviation dictionary. 2014.
Look at other dictionaries:
Flat rated — When an engine is Flat rated it means that an engine of high Horsepower rating is constrained to a lower horsepower rating. The engine output in this case will always remain the same, but when atmospheric conditions such as high temperatures and… … Wikipedia
Engine — This article is about a machine to convert energy into useful mechanical motion. For other uses of engine, see Engine (disambiguation). For other uses of motor, see Motor (disambiguation). A V6 internal combustion engine from a Mercedes car An… … Wikipedia
Volkswagen air cooled engine — Infobox Automobile engine name = E motor aka = manufacturer = Volkswagen type = Flat 4 bore = 75 mm stroke = 64 mm displacement = Auto cc|1131 length = diameter = width = height = weight = block = head = Aluminum valvetrain = OHV supercharger =… … Wikipedia
Jet engine performance — This article describes how jet engine performance is estimated during the design phase. Similar techniques are used once the engine has been built and is being tested, except the performance of individual components, rather than being assumed, is … Wikipedia
Oldsmobile V8 engine — The 1966Toronado s 425 V8, the first post war front wheel drive V8 application. The Oldsmobile Rocket V8 was the first post war OHV V8 at General Motors. Production started in 1949, with a new generation introduced in 1964. Like Pontiac, Olds… … Wikipedia
Chevrolet Corvair engine — Corvair engine Manufacturer Chevrolet Displacement 140 CID (2.3L), 145 CID (2.4L), 164 CID (2.7L) Cylinder block alloy … Wikipedia
Ford Windsor engine — Infobox Automobile engine name = Ford Windsor V8 aka = manufacturer = Ford Motor Company type = V8 bore = stroke = displacement = 221,255,260,289,302,351 length = diameter = width = height = weight = block = Cast Iron head = valvetrain = OHV… … Wikipedia
GM Vortec engine — Vortec is a trademarked name for a line of piston engines for General Motors trucks. The name first appeared in 1986 on a 4.3 L V6 but is now used on a wide range of different engines. Modern Vortec engines are named for their approximate… … Wikipedia
Chevrolet Big-Block engine — The Chevrolet big block is a series of large displacement V8 engines that were developed in the USA during the 1950s and 1960s. As American automobiles grew in size and weight following the Second World War the engines powering them had to keep… … Wikipedia
Buick V6 engine — The Buick V6, initially marketed as Fireball at its introduction in 1962, is a large V6 engine used by General Motors. The block is made of cast iron and all use two valve per cylinder iron heads, actuated by pushrods.The 3800 was on the Ward s… … Wikipedia