Specific Range •Affected by: –Aircraft Gross Weight –Altitude –Aerodynamic configuration of the aircraft 17 . The following formula determines the specific endurance for any given flight condition. Go to Top Final Thoughts . The item of range involves consideration of flying distance, while endurance involves consideration of flying time. To understand the impact this has on endurance, we have to look at brake specific fuel consumption (BSFC). While the peak value of specific range would provide maximum range operation, long range cruise operation is generally recommended at some slightly higher airspeed. specific endurance = ----- lbs. Range Vs Endurance 16 . Range must be clearly distinguished from the item of endurance. V max endurance = V max range = Best Glide Speed V optimum cruise = (Best Glide Speed) * 1.316. Cruise control of an aircraft implies that the aircraft is operated to maintain the recommended long-range cruise condition throughout the flight. 6. Aircraft are not designed solely for cruising; they must also takeoff and climb. maximum specific range varies only about 1 % from the mean value, which is equivalent to less than a 2-knot change intheheadwind ortailwind component. Peaks of the individual specific range (SR) curves occur at the sameCAS, while TAS, P. R, and FF all vary in. Question: What Is The Effect Of Altitude On Specific Endurance For A Jet Aircraft? Flight Planning . Specific Endurance = Flight Hours per Hour / Pounds of Fuel per Hour. 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. As stated earlier, every effort is made to maintain the SG of … So now you can find these speeds for your airplane. A brief discussion on cruise flight performance of piston prop aircraft, including two examples of range and endurance calculations. Specific Endurance = flight hours/pounds of fuel OR flight hours/hour / pounds of fuel/hour ... • Maximum Range = maximum of speed per fuel flow . AP3456 - 2-1 - The Effect of Variation in Specific Gravity of Fuels on Range and Endurance . This is a measure of fuel efficiency within a shaft reciprocating engine. It simply the rate of fuel consumption divided by the power produced and can also be considered a as power-specific fuel consumption. Figure 11: Airspeeds for maximum endurance vs. maximum range. 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). of fuel/hr. 2 proportion to SMOE. Cruise Control. 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