Consider an airplane flying at 620 mi/h at 35,000 ft. Calculate its energy height.
\(v = 620\left ( \frac{5280}{3600} \right ) = 909.333\,ft/s; g = 32.2\,ft/s^{2}\)
Energy height =
\[h+\frac{v^{2}}{2g}=35000 + \frac{909.333^{2}}{2\left ( 32.2 \right )}=47839.853\,ft\]
Consider an airplane in an accelerated climb. At a given instant in this climb, the specific excess power is 120 ft/s
Consider an airplane flying at 620 mi/h at 35,000 ft. Calculate its energy height.
For a turbojet-powered airplane with the altitude variation of thrust given by Eq. (3.19), show that as the altitude increases, the maximum velocity decreases.
The BD-5J is equipped with plain flaps. The airfoil section at the wing root is an NACA 64-212, and interestingly enough, it has a thicker section at the tip, an NACA 64-218.
For the BD-5J, calculate (a) The maximum value of CL/CD (b) The maximum value of CL^(1/ 2) /CD
Maximum lift to drag ratio decreases as the Mach number increases. How to mitigate the effect of decrease in maximum lift to drag ratio when there is increase in Mach number.
Consider the data for the NACA \(2412\) airfoil. Calculate the lift and moment about the quarter chord (per unit span) for this airfoil when the angle of attack is \(4^{\circ}\) and the freestream is at standard sea level conditions with a velocity of \(50 ft/s\). The chord of the airfoil is \(2 ft\).
Consider an NACA \(2412\) airfoil with a \(2\;m\) chord in an airstream with a velocity of \(50\; m/s\) at standard sea level conditions. If the lift per unit span is \(1353\; N\), what is the angle of attack?
Starting with the definition of circulation, derive Kelvin’s circulation theorem.
