Specific Endurance = Flight Hours per Hour / Pounds of Fuel per Hour. 2 proportion to SMOE. So now you can find these speeds for your airplane. Peaks of the individual specific range (SR) curves occur at the sameCAS, while TAS, P. R, and FF all vary in. Aircraft are not designed solely for cruising; they must also takeoff and climb. While the peak value of specific range would provide maximum range operation, long range cruise operation is generally recommended at some slightly higher airspeed. Range Vs Endurance 16 . 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 a result, your airplane is carrying around a lot more power than is required for cruising. Flight Planning . It simply the rate of fuel consumption divided by the power produced and can also be considered a as power-specific fuel consumption. V max endurance = V max range = Best Glide Speed V optimum cruise = (Best Glide Speed) * 1.316. Range must be clearly distinguished from the item of endurance. Figure 11: Airspeeds for maximum endurance vs. maximum range. Go to Top Final Thoughts . This is a measure of fuel efficiency within a shaft reciprocating engine. Specific Air Range & Specific Endurance Key cruise parameters are Range (distance flown) and Endurance (time of flight). Cruise control of an aircraft implies that the aircraft is operated to maintain the recommended long-range cruise condition throughout the flight. To understand the impact this has on endurance, we have to look at brake specific fuel consumption (BSFC). A brief discussion on cruise flight performance of piston prop aircraft, including two examples of range and endurance calculations. As stated earlier, every effort is made to maintain the SG of … Figure. maximum specific range varies only about 1 % from the mean value, which is equivalent to less than a 2-knot change intheheadwind ortailwind component. or 1 ----- fuel flow {p309} If maximum endurance is desired, the flight condition must provide a minimum of fuel flow. If maximum specific range is desired, the flight condition must provide a maximum of speed per fuel flow. 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. The item of range involves consideration of flying distance, while endurance involves consideration of flying time. specific endurance = ----- lbs. 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). 6. of fuel/hr. The following formula determines the specific endurance for any given flight condition. Specific Endurance = flight hours/pounds of fuel OR flight hours/hour / pounds of fuel/hour ... • Maximum Range = maximum of speed per fuel flow . Question: What Is The Effect Of Altitude On Specific Endurance For A Jet Aircraft? Specific Range •Affected by: –Aircraft Gross Weight –Altitude –Aerodynamic configuration of the aircraft 17 . AP3456 - 2-1 - The Effect of Variation in Specific Gravity of Fuels on Range and Endurance . Cruise Control. : What is the Effect of Variation in specific Gravity of Fuels on range and calculations! Pounds of fuel per Hour / Pounds of fuel consumption ( BSFC ) Glide Speed V cruise... 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