Gimli Glider

A Boeing 767 loses both engines at an altitude of 35000 feet. The captain maintains optimal gliding conditions, losing 2100 feet per minute while maintaining a constant airspeed of 201 knots.

Calculate how long it takes for the plane to reach the ground from the moment of engine failure. Calculate how far the pilot glides the plane.

1 foot = 1 ft = 0.3 m
1 knot = 1.9 km/h

Final Answer:

t =  16.7 min
s =  105.5 km

Step-by-step explanation:

$$\begin{gathered} h=35000\text{ft} \\ {s}_1=h\to \text{km}=h:3281\text{km}=35000:3281\text{km}=10.668\text{km} \\ {v}_y=2100\text{ft/min} \\ h=v_y\cdot t \\ t=\frac{h}{v_y}=\frac{35000}{2100}=16.7\text{min} \end{gathered}$$

$$\begin{gathered} v=201\cdot 1.9=381.9\text{km/h} \\ {t}_2=t\to \text{h}=t:60\text{h}=16.6667:60\text{h}=0.27778\text{h} \\ {s}_2=v\cdot t_2=381.9\cdot 0.2778=\frac{1273}{12}\doteq 106.0833\text{km} \\ {s}_2^2=s_1^2+s^2 \\ s=\sqrt{s_2^2-s_1^2}=\sqrt{106.0833^2-10.668^2}=105.5\text{km} \end{gathered}$$

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