[simpits-tech] Hey Wayne, I got a GeneScreen question.....

[Matt Bailey]

I am in the midst of designing a shop for the Sabreliner. I'm trying to
nail down exactly how large my screen is going to be if I build
something like what Wayne and Gene have. I already have that BP screen
from FlightSafety.....the screen will hang above the cockpit, with its
bottom bow starting at about 8ft off the ground.

Here are some quick specs on the screen:

Top bow diameter (corner to corner): 133"
Bottom bow: 124"
FOV: 180*
Height: 48"

Here are a couple pics of the beast:

http://www.flickr.com/photos/alfamatt/9416907015/

http://www.flickr.com/photos/alfamatt/9419673508/ (That weird
reflection on the ground is from the optics of the screen)

Gene indicated that it was a pretty hard and fast rule that my Mylar
frame would have to be exactly twice the size of the BP screen, and
that the screen would not mimic the shape of the BP screen, but would
be a spherical section. Is there any way to make it slightly smaller
(say, 15ft diameter instead of 20ft+++) and still retain the correct
optics? Also, do I base this sizing off the top bow, the bottom bow, or
an average of the two?

I am also not sure how high the Mylar screen needs to be. From pics on 
Gene's site, it looks like it would be placed with its center at the
same Y position as the pilot, but curved in such a way that it
represents a section of a sphere whose center would be the same center
as the BP screen...no?

Matt