Roll program?

[ryan]

Hey guys, i was thinking about the Space Shuttle and i was wondering how it does it roll maneuver, is it gimballing of the SSMS or something else. I was also wondering how the Saturn V, Redstone, Atlas, Soyuz and all them.
Thanks.
Ryan.

 

[markl316]

Pretty sure shuttle is a SSME and SRB gimbal. Probably gimballs for the others too, because they had no aerosurfaces.

 

[Notebook]

I think the Atlas didn't have gimballing engines, it used small vernier rockets for control.

N.

 

[MajorTom]

I've seen a Redstone up close, and it had fins that could swivel.

Wikipedia talks of "Carbon jet vanes, air rudders, spacial air jet nozzles, air vanes" for the steering system:

http://en.wikipedia.org/wiki/Redstone_(rocket)

If you can research and explain all those nozzles and vanes, that'd be nice...

 

[Urwumpe]

Soyuz does not do a roll maneuver - many Russian rockets are rotated on the ground to the right azimuth and launched with a simplified guidance. The same with many current Chinese rockets.

 

[MajorTom]

I'm pretty sure the N1's rolling (launch #3) was not deliberate.

 

[Andy44]

According to Atlas: The Ultimate Weapon by Chuck Walker (outstanding space history book), Atlas sustainer engine gimbaled up to 3 degrees, and the booster engines gimbaled up to 5 degrees, on every Atlas model up to the Atlas IIAS.

 

[Notebook]

Shock Horror, I have the same book! I am now off to re-read, and see where I have gone terribly wrong.

N.

Edit: - It seems I went wrong on page 51..

Well corrected, many thanks. N.

 

[garyw]

Soyuz does not do a roll maneuver - many Russian rockets are rotated on the ground to the right azimuth and launched with a simplified guidance. The same with many current Chinese rockets.

Yes. Soyuz have a "roll table" where they rotate the launcher to the right azimunth and fire.

Shuttle uses TVC (Thrust Vector control) from hydralic pumps in the SRB's. I don't belive the SSME's contribute to the roll.

Daves can give a better answer.

 

[Urwumpe]

Shuttle uses TVC (Thrust Vector control) from hydralic pumps in the SRB's. I don't believe the SSME's contribute to the roll.

No, they are pretty weak in the early phases of ascent. The SSMEs only do load-relief, but take over when the SRB thrust decreases.

 

[garyw]

The SSME's do control the "roll to heads up" around the five minute mark.

 

[DaveS]

The SSME's do control the "roll to heads up" around the five minute mark.

Actually it's more around the 6 minute mark. It is commanded whenever the the stack reaches 12 kfps VI.

 

[joeybigO]

do the elevators and rudder contribute at all? I know they go thru a test with 20 seconds left

 

[DaveS]

do the elevators and rudder contribute at all? I know they go thru a test with 20 seconds left

That test is actually for the SRB TVC. SSME TVC check is at T-3 min, 20 sec. The FCS test is at T-3 min, 50 sec.

The elevons is just used for wing load relief during ascent.