We’re going to the moon. In 12 years.

Well, we’ve got some time to kill.

In the meantime, let’s just all pretend that Apollo is still going on.

This is a simple graph of the G forces experienced during the trip from the launch pad to low earth orbit in a Saturn V. I actually thought they went higher than 4-G during the boost. A note mentions that the highest G-forces the astronauts encounter is during re-entry when they hit about 6.5 Gs. Ooftah.

Here are the explanations of the changes in acceleration:

1. Launch with ignition of the S-IC. Note how the acceleration rapidly rises with increasing engine efficiency and reduced fuel load.
2. Cut-off of the centre engine of the S-IC.
3. Outboard engine cut-off of the S-IC at a peak of 4g.
4. S-II stage ignition. Note the reduced angle of the graph for although the mass of the first stage has been discarded, the thrust of the S-II stage is nearly one tenth of the final S-IC thrust.
5. Cut-off of the centre engine of the S-II.
6. Change in mixture ratio caused by the operation of the PU valve. The richer mixture reduces the thrust slightly.
7. Outboard engine cut-off of the S-II at a peak of approximately 2.7g.
8. S-IVB stage ignition. Note again the reduced angle of the graph caused by the thrust being cut by a fifth.
9. With the cut-off of the S-IVB’s first burn, the vehicle is in orbit with zero acceleration.

From the incredible Apollo 15 – Launch and Reaching Earth Orbit page. (via The Eternal Golden Braid)

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