On Thursday, May 2, 2019 at 9:29:39 PM UTC-7, wrote:
Again, total misinformation and fantasy, never let the truth get in the way of a good story!

The owner of the aircraft was a Pipistrel dealer, a FedEx pilot and also a pilot of the Orbis flying I hospital. He did not offer the pins for sale after the aircraft was written off, he would not want the liability.

Please, you guys need to be a little bit more responsible about this with some of the statements because they are just not true, not even close to the truth.

Again, the manufacturer declared the aircraft condemned after reviewing photographs of the aircraft in the hangar immediately after the smoke cleared.
they got into their documentation and found the information about what temperature the canopy would melt at, this was well beyond what the composite companies/resin manufacturers would allow for the products that are used in this aircraft manufacture and probably any aircrafts manufacture using composite materials.

I would be negligent of both myself and the manufacturer in looking the other way and allowing this aircraft to be sold to some excited pilot only to have the wings fall off days, weeks, months or years later.

The aircraft was condemned for a reason, you need to think, would you allow your wife or grandchildren to fly in this aircraft knowing its history ? (Divorce cases excluded) as mentioned in another email, the FAA are investigating now and I have trust in the system that they will get to the bottom of this

There is an important distinction to be made when considering the effects of temperature on composites.
The epoxy resins used in most wet layups (like those used by just about all glider manufacturers except windward perf.) are actually very sensitive to heat. The exact type of resin used by each manufacturer varies, but as a benchmark the Kaneka Aerospace (Applied Poleramic) SC-14 resin, loses around 50% of its strain energy release rate value by the time it reaches 50 degrees C. Not hot!
Please refer to the following paper from Montana State Univ. regarding the effects of temperature and humidity on composites: http://naturefilm.montana.edu/compos...i%20thesis.pdf

If this taurus were indeed exposed to high enough temperatures for long enough to distort or melt the canopy, I would definitely argue that it has significant composites damage.

If you haven't thought about this before, the reason gliders are white in color is to minimize heat while spending long periods of time in the sun. It is much easier than you probably think to damage the glider by it getting too hot. Ever seen a glider with removed racing stripes?
This is also why wise owners tend to prefer fiberglass-top trailers over metal ones in places that get very hot. As you can imagine, the inside of a metal trailer might easily exceed 50 degrees C (122 deg f) on a hot summer day.

In contrast, pre-preg composites as used by windward composites and most leading aerospace companies, are cured at high temperature in an autoclave and are thus pretty much immune to heat. This is why (when they were in production at least...) you could order a duckhawk or a sparrowhawk in whatever color you wanted. There are also some resins used in wet layups (from my understanding, schleicher has started using these in their newest gliders) that are cured under heat and are not as much affected by heat after cure.

Most of my composites experience is with pre-preg, and despite being more costly than the alternative, it is significantly easier to work with, stronger and less prone to structural changes with exposure to moisture and heat.
I don't foresee the big glider manufacturers making the switch to pre-preg any time soon due to the inherent cost in switching manufacturing methods, but I do hope they switch to it at some point.

Thomas