Thank you martin for your reply. It's most appreciated. I intend to experiment with moving the textures around as per your suggestion but after perhaps trying a newer, better performing video card.

I have heard conflicting ideas reference what is gained by changing video cards but I suppose that it might be a good place to start.

What I've also found confusing is the display issues that seem to crop up with SP2. I have FSX basic with SP1 only. There is one particular aircraft that loads fine on my SP1 FSX yet loads with the 'black glass' on a friend's FSX with SP2.

OTOH, I have three other aircraft that load with the 'black/missing glass' problem on my FSX SP1 yet others have reported that these same files load properly on their FSX SP2.

This seems to indicate that this problem is most certainly particular to the respective individual aircraft files themselves as you've pointed out...

Although this item started up a long time ago I have a comment to add. In FSX PS2 often black (non-transparent)glass textures are caused by white alphalayers in the glass texture. Changing the colorvalue of the alphalayer to something like black (say RGB 0,0,0) or gray (say RGB 70,70,70 )gives you variants from totally transparent to smooky glass. So open up your glass texture p.e. with DXTBmp and rework the alphalayer with a suitable graphics program. Save it back to DXTBmp and save the results in DXTBmp to the original glass texture. Hope this helps a bit.