For balance problems - I was under the impression that shuttle engines are vectorable. Attachment support would have to be engineered in.
What ya gona do bout that big ol' vertical stabilizer. Kinda in the way.
Regardless, why would you want to carry/expend fuel for "balance"?
Doesn't that sort of add to the already poor economics?
GSlob: For balance problems - I was under the impression that shuttle engines are vectorable. Attachment support would have to be engineered in.The STS main engines (as well as the SRBs) are indeed dual gimbal.
Each engine can be gimbaled plus or minus 10.5 degrees in the yaw axis and plus or minus 10.5 degrees in the pitch axis for thrust vector control by hydraulically powered gimbal actuator.However, the bulk of the thrust comes from the SRBs. The original vision for the shuttle was a vehicle which could both take off and land like a plane (I think that's what dhuffman@awod.com referred to above. That proved to be too much to engineer (and the engineering was superb back then as well), so we wound up with a rocket launch and glider reentry / deadstick landing.