[vrinsd]

Anyone who wants a genuinely detailed treatment of this subject should read Allan McDonald's book "True, Lies O-rings" *. I happened to have finished this a few weeks ago and it goes on my list of all "engineers should read this".

This was really one of the most fascinating books I've read and likely the most definitive treatment of the subject by a subject matter expert. I kind of skimmed the blog article, the book explains in critical detail the issues with the original design and why the re-design (done after the disaster) was a much more robust approach.

In a nutshell the Shuttle SRB field-joint design was taken from a Titan missle design that was deemed to be "solid engineering" because none had blown up, but Allan mentions the SRB field-joint was flawed from the start and the joints suffered rotation and physically moved / flexed. (Later, it turns out a Titan missle exploded and the teardown showed the o-rings a primary point of failure).

Allan mentions it was the blowby past the o-rings that was consistently the issue and the engineers wanted to understand and address this problem for a long time.

What was striking to me, beyond the technical aspects of making these things work is the actual cover-up and attempt on NASA+Thyokol to blame McDonald and others for the resulting disaster. I knew of some parts of this, but you don't realize how messed up the situation was/is until you read the book.

Personally I'd ignore any negative reviews of the book, I think non-engineers, especially those who haven't worked in an Aerospace/Defense environment or in a big company might think Allan is arrogant or boasting, but he starts by providing the foundation for his statements before getting into the details which is a classic "engineer's engineer" way of thinking.

* https://www.goodreads.com/author/show/2101296.Allan_J_McDona...

[bayouborne]

quick typo correction, 'Truth, Lies, and O-Rings'