[kens]

A few random comments:

There's a video of the Soyuz explosion mentioned above at http://www.youtube.com/watch?v=UyFF4cpMVag&noredirect=1 that shows the escape system saving the crew.

The use of solid rocket boosters for human space flight (as was planned for Ares I) is hugely controversial because they can't just be shut down in the event of a problem, as regular engines can, making survivability more difficult.

Personally, I think NASA is overly risk-adverse, to the point that nothing gets accomplished (see Constellation / Ares I). An interesting article on this is http://www.popularmechanics.com/science/space/news/4330356

On the topic of aircraft turbine failures, there's the interesting case of a DC-10 engine that disintegrated in flight due to a pilot experiment, killing a passenger. For details see: http://en.wikipedia.org/wiki/National_Airlines_Flight_27

Finally, if you're interested in SpaceX, NASA budgeting, and so forth, I recommend http://nasawatch.com