January 25th, 2003

When we built the 2nd generation screen using .030 ABS plastic as the
screen, we figured we had it made.  Unfortunately, the plasic cut so much
light that the resulting projection was very hard to see.  Nothing was
visible at night, including the runway lighting.  It was a good idea that
just didn't work out as planned.  These things happen periodically. 
However, we do learn a lot between generations.

The less than stellar performace found with the 2nd gen screen lead to the
3rd generation screen that we built last week.

The frame is built from 2x4 pine lumber with 6 steel "L" brackets per corner
(2 on each side, 1 on the inside corner and 1 on the outside).  This frame
is a LOT sturdier than the last.  It has almost no flex or twist to it at

"Will you put that f'ing camera away and pick up a broom for once?"

The frame is 9 feed wide and 8 feet high.  The prior screen had the same
width, but was only 3 feet high.  I wanted to try a new location for the
screen.  Instead of sitting right in front of the windscreen, I wanted it
positioned about 4 feet ahead - right at the nose.  The hope was for a
better scene.

The screen material is an untreated Queen sized flat sheet.  We stretched it
across the frame and fixed it in place using ripped down 2x4 as cap strips. 
It's VERY tight.  So much so that you can fling a quarter at it and it'll
gladly ping you in the forehead on its return trip.

This is what the new screen looks like when hung and ready to go.

It's pretty impressive when you're standing right next to it.  

It was time to see if this new screen would do the job.

The image display was *perfect*!  I couldn't have asked for a better result
with this test.  The scene is a lot brighter than what can be seen in the
picture.  My digital camera can't do it justice.

Here's a shot of Rob taking a spin.  I still tease him about lawn darts
after the "incident" with the Alaska Airlines MD-83 simulator a number of
years ago.

While this was a successful test of a new screen material, the screen as a
whole didn't do as well as I'd hoped.  The 4th generation screen to be built
will retain the size of this screen, but be positioned right ahead of the
windscreen like the 2nd generation screen was.  The hope is that this will
provide the maximum amount of forward view area possible with the projection
method I'm currently using.

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