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I have seen many questions answered about the roll program with relation to the shuttle launch and reducing stresses on the launch vehicle and various other reasons, but why was the roll program needed for the Saturn five rocket being a circular vehicle. Having watched films of other launch's in different countries using circular rockets, they do not appear to go through a roll program or is it carried out at a different part of the launch procedure.

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  • $\begingroup$ I'm pretty sure that the main reason they did this for the space shuttle is so that the pilots could see the ground as a safety precaution (if all else failed, they could theoretically fly without instruments in an abort manoeuvre), so it may have been the same reason for Saturn (there were only small windows in the Apollo spacecraft on one side). But then this raises the question of why they didn't arrange the launch so that the windows were on the side towards the downrange component of the climb - more so for Saturn than SS (which likely had a natural optimal takeoff orientation). $\endgroup$ Commented Sep 10, 2014 at 8:07
  • $\begingroup$ @WetSavannaAnimalakaRodVance as best I recall, the emergency separation protocol for Apollo was not under astronaut control, but in any case what they might see thru the window would have been entirely irrelevant. It wouldn't surprise me if the roll is an efficient, lower-stress way of changing the rocket's attitude away from vertical. $\endgroup$ Commented Sep 10, 2014 at 11:42
  • $\begingroup$ @CarlWitthoft You're right about emergency for Apollo - its protocol used the escape rocket (which of course the shuttle lacked) - but I thought either astronauts, ground control, range safety officer or even certain states of the flight computers could equally well trigger the escape lifter. Anyhow, my point was that the roll could have a trivial reason, but your speculation seems more likely. $\endgroup$ Commented Sep 10, 2014 at 11:50
  • $\begingroup$ @CarlWitthoft Also, your comment is in keeping with the Phillip's observations that the roll is not done for other rockets - the Saturn was such a whopper that stress considerations were likely to be much more important than for many of the rockets of today. $\endgroup$ Commented Sep 10, 2014 at 11:59
  • $\begingroup$ Also related: Pitch and yaw axes of rocket systems such as Apollo $\endgroup$
    – TildalWave
    Commented Sep 10, 2014 at 17:55

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