Space Shuttle Program Launch Pad Aborts

Judy Resnik was aboard the first one on here. God bless you Judy! You, Dick, Mike, Christa, Greg, Ron and Ellison are forever in my heart.

2:32 - look at that swinging motion, the inertia of the whole aggregate is simply collosal.

These engines depend on burning the fuel to cool themselves, paradoxically, so when the suddenly have to shut down it's a big deal and the fuel pumps have to be shut down immediately to prevent a catastrophe - this makes a fantastic groaning sound you can hear at about 2:10 and after. It's hard to stop those pumps!

Thanks for posting. I don't know in anyone knows this, but NASA's first RSLS abort was on December 12, 1965 within the Gemini program. Right after countdown, Gemini 6's engines had shut down. I would like to see a video of that event.

What is RSLS ?

RSLS stands for Redundant Set Launch Sequencer.  Starting at 0:15 into the video, you can hear one of the ground controllers say "We have an RSLS abort."

OK I got it. The back up launch sequencer failed. Thanks...

Another interesting fact...the main engines on the shuttle can be turned off in case of emergency. The solid rocket boosters cannot be turned off once they are fired.

Those sparks are to burn of any residual hydrogen which may be present near the main engines at ignition. A lot of people think those sparks actually ignite the engines, like you would light a gas hob with a spark, but thats not true :-)