In the "for what it's worth column"--

     Subject: firewall blanket protection.

Several months ago I was removing my exhaust system for top overhaul/Jet Hot coatings and was particularly interested in my firewall blanket and several areas of the aluminized coating had come loose and or off. I started to remove some of it and I discovered that BEHIND a perfectly normal piece of the blanket I had a blackened/totally charred 6 inch in diameter piece of pre-preg firewall.

My analysis was that during an exhaust crack event well over a year ago had sprayed exhaust on the firewall blanket from a distance of about 14 inches and while the blanket had not discolored or gave any indication of thermal distress--the pre-preg behind it had not fared well at all.

After repairing the pre-preg I repaired the original blanket and put a 2000° Thermo-Tec blanket on top. I have since tested that combination-- and I am not too pleased.

I would have to say that the blanket protection we have is marginal at best. While my cracked exhaust event was probably in the neighborhood of two hours or more exposure-- I sincerely think we need to have a indication of what is going on in our assessory section. We need to have a system that is error and false alarm -free. A verification system of some sort to prevent panic/overreaction.

I am currently looking at--

http://www.acroname.com/robotics/parts/R67-UVTRON.html

backed up (verified) by a standard outside air temperature gauge placed in gascolator area.

Anyone have a better idea?