Newbie query: _How_ is the shuttle roll manoeuvre performed?

On Fri, 29 Aug 2003 15:13:13 +0100, Trust No One® wrote:

Before anyone flames me I'm not asking WHY the shuttle roll is performed but
rather HOW the manoeuvre is executed.

I did find an reference in the book "Voyage into History" by James Harwood
to the effect:

"The shuttle's computers moved the booster nozzles in opposite directions to
roll Challenger about its vertical axis so as the ship climbed toward space,
the shuttle would be positioned below the external tank with the crew upside
down relative to Earth and the shuttle's wings level in relation to the
horizon"

Is the author referring to the SRB nozzles?

Yes. Attitude control on ascent is by gimbaled nozzles.

http://www.spaceflight.nasa.gov

--
Chuck Stewart
"Anime-style catgirls: Threat? Menace? Or just studying algebra?"