ABSTRACT
The designer of an aircraft engine must recognize the differing requirements for takeoff, climb, cruise and maneuvering, the relative importance of these being different for civil and military applications and for long-and short-haul aircraft. In the early aircraft, it was common practice to focus on the take-off thrust. This is no longer adequate for later and present day aircraft. For long-range civil aircraft such as Boeing 747, 777, and Airbus A340 as well as the future Boeing 787, Airbus A380 (the world’s truly double-deck airliner), and A350 XWB (extra wide body expected in 2012), the fuel consumption through some ten or more flight hours is the dominant parameter. Military aircraft have numerous criteria such as the rate of climb, maneuverability for fighters, short takeoff distance for aircraft operating from air carriers and maximum ceilings for high-altitude reconnaissance aircraft such as SR-71 Blackbird aircraft. For civil and military freighter airplanes the maximum payload is the main requirement.
