The following formula determines the specific endurance for any given flight condition. V max endurance = V max range = Best Glide Speed V optimum cruise = (Best Glide Speed) * 1.316. Go to Top Final Thoughts . Range Vs Endurance 16 . It simply the rate of fuel consumption divided by the power produced and can also be considered a as power-specific fuel consumption. Specific Air Range & Specific Endurance Key cruise parameters are Range (distance flown) and Endurance (time of flight). 2 proportion to SMOE. maximum specific range varies only about 1 % from the mean value, which is equivalent to less than a 2-knot change intheheadwind ortailwind component. To understand the impact this has on endurance, we have to look at brake specific fuel consumption (BSFC). 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? Specific Endurance = Flight Hours per Hour / Pounds of Fuel per Hour. of fuel/hr. Range must be clearly distinguished from the item of endurance. Cruise Control. This is a measure of fuel efficiency within a shaft reciprocating engine. specific endurance = ----- lbs. Flight Planning . As a result, your airplane is carrying around a lot more power than is required for cruising. 6. The item of range involves consideration of flying distance, while endurance involves consideration of flying time. Aircraft are not designed solely for cruising; they must also takeoff and climb. 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). or 1 ----- fuel flow {p309} If maximum endurance is desired, the flight condition must provide a minimum of fuel flow. Specific Range •Affected by: –Aircraft Gross Weight –Altitude –Aerodynamic configuration of the aircraft 17 . 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 . So now you can find these speeds for your airplane. While the peak value of specific range would provide maximum range operation, long range cruise operation is generally recommended at some slightly higher airspeed. 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 … 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. Cruise control of an aircraft implies that the aircraft is operated to maintain the recommended long-range cruise condition throughout the flight. Figure. If maximum specific range is desired, the flight condition must provide a maximum of speed per fuel flow. 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. = ( Best specific endurance aircraft Speed V optimum cruise = ( Best Glide Speed V optimum cruise = Best. €“Aircraft Gross Weight –Altitude –Aerodynamic configuration of the aircraft 17 required for cruising ; they must also and! 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