Distance between runway and pilot position along the ground is 285430.9336 feet that is 53.9464 miles.
Given that
Height of position of pilot from the ground = 30000 feet
Angle of depression when he looks down at runway = 6o
Need to measure along the ground, distance between runway and pilot that is horizontal distance between runway and pilot.
Consider the figure attached below
D represents position of runway.
P represents position of pilot.
PG represents height of position of pilot from the ground that means PG = 30000 feet
PH is virtual horizontal line and HPD is angle of depression means ∠ HPD = 6 degree
AS DG and HP are horizontals, so DG is parallel to HP.
=> ∠ HPD =∠ PDG = 6 degree [ Alternate interior angle made by transversal PD of two parallel lines ]
We need to calculate DG
Consider right angles triangle PGD right angles at G
[tex]\text {As } \tan x=\frac{\text { Perpendicular }}{\text { Base }}[/tex]
[tex]\tan \angle \mathrm{PDG}=\frac{\mathrm{PG}}{\mathrm{GD}}[/tex]
[tex]\begin{array}{l}{=>\mathrm{GD}=\frac{\mathrm{PG}}{\tan \angle \mathrm{PDG}}} \\\\ {=>\mathrm{GD}=\frac{30000}{\tan 6^{\circ}}=285430.9336}\end{array}[/tex]
As one foot = 0.000189 miles
[tex]=>285430.9336 \text { feet }=285430.9336 \times 0.000189 \text { miles }=53.9464 \text { miles. }[/tex]
Hence distance between runway and pilot position along the ground is 285430.9336 feet that is 53.9464 miles.
