Monday, 4 July 2005

O rings, Feynman and Discovery Shuttle

When the Challenger Shuttle, the one with the teacher on board, blew up in January 1986 I wondered in the aftermath about the O rings mentioned on the news. I never could understand how these little O ring seals could cause the rocket to blow up on take off and then I read my latest Richard P Feynman book "What do you care what other people think?". (I'd already read and reviewed a previous Feynman book)

I may not have read the news or paid attention as well as I could have back then, but I'm also pretty sure it just wasn't explained clearly enough. After all, I did have pictures in my mind of these little plumbing size rubber rings so I must have thought about it a bit.

Feynman, as a Nobel Prize winning physicist was on the panel to investigate the Challenger disaster. He was supposedly key to discovering what went wrong but it is most likely that he was the pawn to reveal and explain what went wrong. A good portion of this book is dedicated to discussing his "last great adventure" which was to be involved in this important commission. As it says in the book, this section was presented in great detail because it was still relevant and it sure is. The Columbia shuttle blew up on re-entry in 2003 losing all crew. That was a completely different accident to the Discovery one.

A date of 13 July 2005, in just a few days, has been given to launch the Discovery Shuttle. There have been delays and concerns over safety. I hope it is delayed rather than cut corners.

But back to those O rings. The rockets either side of the shuttle are made of sections. These sections have joints to connect them and hold them together. In each joint are two rubber rings as a seal to stop the ignited rocket fuel inside coming out. These rings are round, about 1cm thick and about 12 foot across. They only have the tiniest of compression which means they are not that squeezed in because they rely on the intense heat of the rockets to cause the special rubber to swell and perfectly seal the gap. On the day of the launch, on a January morning in 1986, the weather was freezing. The rubber froze and did not react to the heat in time, meanwhile the rocket casing expanded and bowed outwards so the ignited fuel was able to escape out of a safety side vent which is used for testing only. It is like a glorified cork bung and was also badly sealed. *

That was it. Stupid little rubber and a course of management bungles that didn't listen to what the engineers on the ground were saying. All that technology and it comes down to glorified rubber washers.

This is another great book about Feynman's life. Not as funny, more poignant, but definitely a must-read!

And as for the Discovery Shuttle - did you know we are about to have another space launch? May it go well for these great and brave explorers of ours.

* Please note that this is my interpretation of what I have read and may not be an accurate understanding. It is worth reading for yourself.

Original Comments:

Cheryl said...
I was thinking grommets. 12 foot? Wow.
Monday, July 04, 2005 9:38:00 AM
doris said...
So it wasn't just me then!
Monday, July 04, 2005 9:43:00 AM
MrsDoF said...
It's a good thing Feynman did not start a religious cult, what with his ability to bring difficult ideas to light.
Keep on with the good reading!
Monday, July 04, 2005 1:45:00 PM
doris said...
Thanks MrsDof!

I can't believe it, but everywhere I turn now Feynman's name crops up. He was such an odd-ball character but best of all I like the way he tries to remove the waffle. He'd have been an unlikely candidate for a religious cult because of the way he really seemed to play himself down.
Monday, July 04, 2005 2:12:00 PM
Chris said...
I second your best wishes for the next scheduled launch. It's easy to forget about the Challenger accident and the explosion that happened a year or so ago. Space travel is relatively safe, but it is still entering a new frontier. It's amazing how we don't pay that close attention to it unless something bad happens.

Deliberate Chaos
Monday, July 04, 2005 7:33:00 PM
Milt Bogs said...
House party at 2,000-acre estate in Oxfordshire.
Monday, July 04, 2005 9:16:00 PM
jane said...
wow, i normally hate science & stuff like that, but you actually explained it to where i could follow it.
i think the july 15th date was put off.
Tuesday, July 05, 2005 2:35:00 AM
doris said...
Jane - that's down to the excellant explanations of Dick Feynman. He takes the mystery out of these things and just says it as it is so that it means something. His books are worth reading and have given me quite a confidence boost as a result.

Thanks for that Milt! Milt's blog explains it all.
Tuesday, July 05, 2005 9:11:00 AM
WarpedTourMom said...
I had heard "o-rings" but was always embarassed to admit I never knew what they were.

And I'd bring them up in conversation about the Shuttle too, like I knew what I was talking about "Oh yeah, well, you know, those o-rings.."
Tuesday, July 05, 2005 12:14:00 PM
Bernadette said...
My husband and I love to read Feynman!
Wednesday, July 06, 2005 6:07:00 AM
Elvis Blanco said...
Sorry for omitting to sign - I posted the above.
Sunday, December 11, 2005 5:04:00 PM

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