Problem 9: A frequently quoted rule of thumb in aircraft design is that wings should produce about 1000 N of lift per square meter of wing. (The fact that a wing has a top and bottom surface does not double its area.) Part (a) At takeoff, an aircraft travels at 69 m/s, so that the air speed relative to the bottom of the wing is 69 m/s. Given the sea level density of air to be 1.29 kg/m³, how fast must it move over the upper surface to create the ideal lift? Numeric : A numeric value is expected and not an expression. V2 = Part (b) How fast must air move over the upper surface at a cruising speed of 244 m/s and at an altitude where air density is one-fourth that at sea level? Numeric : A numeric value is expected and not an expression. V2 =

Problem 9: A frequently quoted rule of thumb in aircraft design is that wings should produce about 1000 N of lift per square meter of wing. (The fact that a wing has a top and bottom surface does not double its area.) Part (a) At takeoff, an aircraft travels at 69 m/s, so that the air speed relative to the bottom of the wing is 69 m/s. Given the sea level density of air to be 1.29 kg/m³, how fast must it move over the upper surface to create the ideal lift? Numeric : A numeric value is expected and not an expression. V2 = Part (b) How fast must air move over the upper surface at a cruising speed of 244 m/s and at an altitude where air density is one-fourth that at sea level? Numeric : A numeric value is expected and not an expression. V2 =