Consider a Boeing $737-300$ that is cruising at Mach $0\mathrm{.}8$ at an altitude

of $h=30,000ft.$

The temperature is $T=-44\mathrm{.}4C$ and the density is $=0\mathrm{.}459k\frac{g}{m^3}.$

What is the cruise speed in $\frac{m}{s}?$

The wing planform area is $S=91\mathrm{.}0m^2$ and the wing span is

$b=28\mathrm{.}35m.$ What is the aspect ratio?

The wing planform efficiency factor is $e=0\mathrm{.}7$ and the base drag

coefficient is $c_{D0}=0\mathrm{.}019.$ Compute the lift induced drag constant,

$k=\frac{1}{Ae}.$

The initial weight at the start of cruise $(=$MTOW rough estimate$)$

is $W_{\text{i}\text{m}\text{i}\text{t}}=56,470kg.$ Provide the lift and drag coefficient.

Correct the drag coefficient for compressible flow effects,

$c_{\text{D}\text{a}\text{n}\text{n}\text{e}\text{s}\text{e}\text{d}}=\frac{c_D}{1-M^2}.$

What is the lift$-$to$-$drag ratio $($using $c_{\text{D}\text{o}\text{m}\text{o}\text{n}\text{s}\text{e}\text{s}}?$

The fuel tank capacity is $16,000kg.$ Out of that, $15,083kg$ of fuel

are burned $($leaving a reserve of $917$ kg $).$ What is the final airplane

mass at the end of the cruise?

Assume a thrust specific fuel consumption

$TSFC=0\mathrm{.}6\frac{l\frac{b}{h}r}{l}b=\frac{0\mathrm{.}6}{3600}\frac{l}{s}.$ What is the range in miles?

At the beginning of cruise, what is the drag force $($using $c_{\text{D}\text{o}\text{w}\text{n}\text{e}\text{s}\text{e}\text{l}}?$

What is the approximate fuel flow rate in $k\frac{g}{s}?$ Get this from

TSFC$,$ assuming $T=D.$

For a fuel reserve of $917$ kg $,$ for how many minutes can the

aircraft continue cruise at $M=0\mathrm{.}8$ before the tank runs empty?