Heads down or heads up?

I've just downloaded the STS-114 webcam movie and was somewhat
surprised to see the Shuttle roll over 180 degrees on its way to orbit.
I thought it maintained a heads-down attitude during ascent?

Paul

wrote:
I've just downloaded the STS-114 webcam movie and was somewhat
surprised to see the Shuttle roll over 180 degrees on its way to orbit.
I thought it maintained a heads-down attitude during ascent?

Not anymore, it changed a few years back. If I remember correctly it's
a little more fuel-efficient and allowed them to eliminate a tracking
station in the Atlantic (Bermuda maybe?): a 'heads up' shuttle can
communicate through TDRS rather than a ground station.

Mark

In article . com, wrote:
I've just downloaded the STS-114 webcam movie and was somewhat
surprised to see the Shuttle roll over 180 degrees on its way to orbit.
I thought it maintained a heads-down attitude during ascent?

Most of powered ascent as heads-down, but not all of it.

It does a Roll-to-Heads-Up maneuver which improves the communications
and tracking situation and allowed them to close the Bermuda ground
station as a cost-saving measure.

It also allows the Shuttle to acquire the TDRS satellites about 2 1/2
minutes sooner, too.

This occurs around 5m47s into ascent.

Trivia: STS-87 on November 19, 1997 was the first mission to use this.

-Dan