of fuel/hr. Figure. Figure 11: Airspeeds for maximum endurance vs. maximum range. A brief discussion on cruise flight performance of piston prop aircraft, including two examples of range and endurance calculations. maximum specific range varies only about 1 % from the mean value, which is equivalent to less than a 2-knot change intheheadwind ortailwind component. As stated earlier, every effort is made to maintain the SG of … Specific Range •Affected by: –Aircraft Gross Weight –Altitude –Aerodynamic configuration of the aircraft 17 . Specific Endurance = Flight Hours per Hour / Pounds of Fuel per Hour. The following formula determines the specific endurance for any given flight condition. 6. Peaks of the individual specific range (SR) curves occur at the sameCAS, while TAS, P. R, and FF all vary in. Go to Top Final Thoughts . or 1 ----- fuel flow {p309} If maximum endurance is desired, the flight condition must provide a minimum of fuel flow. Range Vs Endurance 16 . It is important to be able to relate these to the amount of fuel burned; in particular, it may be desirable to maximize the range or the endurance for a given quantity of fuel. This is a measure of fuel efficiency within a shaft reciprocating engine. Specific examples of aircraft designed for these conditions include Burt Rutan s Voyager (maximum range), Unmanned Aerial Vehicles (maximum endurance), U-2 reconnaissance aircraft (maximum range and altitude), and the P-3 Orion submarine hunter (maximum endurance). Cruise Control. Cruise control of an aircraft implies that the aircraft is operated to maintain the recommended long-range cruise condition throughout the flight. So now you can find these speeds for your airplane. Thrust Specific Fuel Consumption Is Lower Due To Lower Temperature Thrust Required (drag) Remains The Same At Best Endurance Airspeed Regardless Of Altitude Fuel Flow Is Lower At Higher Altitudes Up To The Tropopause So Specific Endurance Is Improved. It simply the rate of fuel consumption divided by the power produced and can also be considered a as power-specific fuel consumption. Specific Endurance = flight hours/pounds of fuel OR flight hours/hour / pounds of fuel/hour ... • Maximum Range = maximum of speed per fuel flow . specific endurance = ----- lbs. Question: What Is The Effect Of Altitude On Specific Endurance For A Jet Aircraft? 2 proportion to SMOE. To understand the impact this has on endurance, we have to look at brake specific fuel consumption (BSFC). As a result, your airplane is carrying around a lot more power than is required for cruising. The item of range involves consideration of flying distance, while endurance involves consideration of flying time. If maximum specific range is desired, the flight condition must provide a maximum of speed per fuel flow. AP3456 - 2-1 - The Effect of Variation in Specific Gravity of Fuels on Range and Endurance . 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