Re: Oak heatshields
Oak is a particularly fire-resistant timber because it is very strong and dense so that it chars rather than burns, forming a protective layer of charcoal that keeps oxygen at bay. This is recognised (or certainly used to be) in the UK Building Regulations for fire resistance and it makes oak a more economic building material than you might expect. Run that up to Mach 20 or whatever and it becomes an ablative or sacrificial material similar to that used on the original American X-15 sub-orbital rocket plane. Oak is kinder to the environment than that disgusting and toxic chemical brew, too. I don't know about the weight though, that would add a lot to the fuel costs.
Biting the hand that feeds IT
