Originally Posted by dbohemian
Um, Don't know how serious this post was but of course the loss of the Space shuttle Columbia was due to a catastophic failiure of the leading edge of the wing which was a piece of Carbon-Carbon RCC tile. Carbon is an excellent refractory material but lacks impact resistance. The SR-71 dealt with heating very similar to the Shuttle at a lower intensity and used Titanium for this purpose and never once failed. There were better the day they retired them then when they were new.
New materials such as zirconium diboride may hold promise as being a replacement for RCC and have better reliability.
Honestly, The Shuttle is not a good example for this. It is a 40 year old design. Much of the choices made in its construction were as much politically motivated and done for the cool factor as anything else and if the leading edge had been backed with Titanium or Inconel, there may have been a chance for that crew to still be alive.
Carbon bikes are generally reliable. What scares me is that they are much more open to construction errors and poor engineering than metal materials.
Dave Bohm
Bohemian Bicycles
Really?! Maybe I am wrong, but I thought it was determined that it was a failure in the plastic O-rings that held the
steel SRB (solid rocket booster) plates together. The O-rings couldn't handle the heat that was transmitted from the SRB plates upon entry into the atmosphere. Maybe, they should've used carbon?
"Several engineers—most notably Roger Boisjoly, who had voiced similar concerns previously—expressed their concern about the effect of the temperature on the resilience of the rubber O-rings that sealed the joints of the SRBs. They argued that if the O-rings were colder than 53 °F (approximately 11.7 °C), there was no guarantee the O-rings would seal properly. They also argued that the cold overnight temperatures would almost certainly result in SRB temperatures below their redline of 40 °F. However, they were overruled by Morton Thiokol management, who recommended that the launch proceed as scheduled.[4]"
more can be read here:
http://en.wikipedia.org/wiki/Space_S...enger_disaster