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I happen to be one of the people that has experienced a window blow out at FL 230, so I think I have some first hand knowledge.  I do not need to go into all the details, but will provide a few.  Our plane had 60 Hrs. with most of the flights pressurized.  We pressure tested the fuselage on the ground to 7 psi.  The day we took off, the temperature in FL was around 90 degrees( guess the temp. on the ramp?).  Climb to FL 230, temp at 230?  Below -10. Climb time 20 min.  What is the difference in expansion rate between plexiglas and carbon-fiber?  Our window was built before the SB.  The installation done exactly as the book said.  The window cracked from front hole to back, the whole lower half of the window then departed the aircraft.  In talking to Lance, after the incident, a fix was decided on.  Enlarge the hole in the Plexiglas to allow for expansion.  When we sold the plane, we had close to 300 hrs without any problems.  I drilled a hole in the glass a lot bigger than the SB calls for, because I was the fix before the SB.  The hole in the glass was 3/8", then filled with pro-seal, glassed in, then drilled thru the pro-seal to install the bolt thru the two outer sandwich layers.  This way the glass can "float" between the layers and the bolt, not putting any stress on the glass from the bolt.  I put the new window in from the outside, laying new carbon on the outside of the window, with the door closed and in place as to not change my alignment on hinges and door latches. We were back in the air in less than a week.  If anyone has built their door prior to the SB and not re-drilled their holes, DO NOT fly your craft pressurized, until you modify your bolt holes.  Lancair planes and people are great, that's why I'm building a 360 now, just can't do without a Lancair.. Doug,  A&P/IA
    

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