wrote in message
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On Sun, 29 Jun 2008 17:47:58 -0400, Stuart Wheaton
wrote:

wrote:
Whenever the launch is shown there is a shot of the exhaust coming out
of the rockets. And there is always in the shot a device that shoots
out sparks horizontally. What is the spark shower for?
Eric

Those are Hydrogen Burn Off Initiators.

They are meant to keep leaking or unburned hydrogen fuel from a failed
engine start from accumulating to explosive levels.

Good Video:

http://www.youtube.com/watch?v=IFXVxc6ms1U

Stuart
Thanks Stuart. I always figured that they couldn't possibly be for
lighting the engines. If they were, then they would need to be
blasting off with the shuttle. Either that, or some astronaut would
need to go on an EVA with a striker. I can just see this poor
spacesuited figure holding a striker around the edge of a rocket
nozzle.
Eric

I'm late on this, but I saw a program a long long time ago that said they
were to ignite gases around the base. I thought that plausible, but then
looking at that huge friggin solid propellant blowtorch going off, I
wondered what extra gas could be hanging around and not ignited. I guess
that's why they're sitting there in Mission Control and I'm sitting here in
Buck Snort.

As an aside, I nominate Cliff Culprick (sp?) for the job.

Steve