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Old 3rd Sep 2003, 21:32
  #102 (permalink)  
RatherBeFlying
 
Join Date: Sep 2001
Location: Toronto
Posts: 2,561
Received 42 Likes on 21 Posts
Good spot gordinho.

Looking closer at the forward fuselage you can see a reflection of the runway itself, dark grey about the centreline and a bit of green at the edges.

Now for a bit of optics: The angle of reflection from a "flat" surface is equal on both sides -- say about 1 degree above horizontal to a fuselage inclined at 10 degrees; so about 11 degrees to and from the fuselage. To complete the optic triangle, lets postulate a downslope of 1 degree from the camera to the runway threshold which gives a triangle of 2 degrees at the camera (180 - 2 x 11) = 158 and finally 20 degrees at the runway

The triangle from the runway reflection straight down would yield a right triangle with an angle of about 70 degrees at the a/c. With a height of say 50 feet, the runway markings would be 50 x tan 70 = 50 x 2.74 ~= 135 behind the reflection. The wheels would be approx 100 feet closer to the runway and lower. This yields the wheels approx. 30 feet past the part of the runway shown in the reflection.

Note that the end of the runway does not show in the reflection.
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