2. Flight Mechanics

Performance Optimization — Quiz

Test your understanding of performance optimization with 5 practice questions.

Practice Questions

Question 1

In flight trajectory optimization, the cost function typically represents which quantity to be optimized?

Question 2

In optimal control theory applied to flight trajectory optimization, which principle provides the necessary conditions for an optimal solution?

Question 3

Using the Breguet range equation $R=\frac{V}{c}\frac{L}{D}\ln\frac{W_i}{W_f}$, calculate the range for $V=450\,\text{knots}$, $c=0.55\,\mathrm{hr}^{-1}$, $L/D=15$, $W_i=100{,}000\,\mathrm{lb}$, $W_f=80{,}000\,\mathrm{lb}$, and $\ln(1.25)\approx0.2231$.

Question 4

For a jet aircraft loitering, endurance $t$ is given by $t=\frac{L/D}{c}\ln\frac{W_i}{W_f}$. If $L/D=14$, $c=0.6\,\mathrm{hr}^{-1}$, $W_i/W_f=1.2$, and $\ln(1.2)\approx0.1823$, what is $t$?

Question 5

If the cost index (CI) in a flight management system is set to zero, which cruise speed will the system select?