Low and High Q Ascent.

[nitin52]

What is the difference between a Low Q ascent and a High Q ascent? Looks like STS-115 will have High Q ascent. Any detail info low and high Q ascent? Thanks.

[Chris Bergin]

Yeah. I've written a couple of articles on this....welcome to the site, by the way.

http://www.nasaspaceflight.com/content/?cid=4696

http://www.nasaspaceflight.com/content/?cid=4444

For those on L2, we have the NASA document "Low Q vs High Q" - which was presented to the all-powerful NASA PRCB meeting, and a damn interesting read. Pretty sure this came up in the MOD FRR documents, but I'm still reading through all of those, so can't be specific. For those not on L2, the first link was written from part of that document.

STS-115 is a High Q ascent profile because it is a very heavy payload.

We have some engineers on here who might be willing to add some of their reasoning into this, although it would be a good idea to place "Low Q" into the search, because we've got three or four threads on this already running on the site.