What you have to remember about rockets
is that they weigh a hell of a lot on launch, and the majority of it is due to the mass of fuel. So as the fuel burns off, the thrust, which remains essentially constant throughout, causes the acceleration to increase.

Once most of the fuel has burned off, the rocket's a fraction of its launch mass and hence the acceleration is several g.
( K2k6 has a proper job these days, Tue 30 Jun 2009, 11:08, 1 reply, 17 years ago)

This is the mistake I made when I originally did the calculation
Came out somewhere in the region of 300mph as I hadn't factored in the mass of it at launch and did a calculation based on the final speed at the end of the first stage, forgetting that the acceleration would keep rising. I've redone my figures though and I can see where I went wrong with this - will try to remember if I have to sue them in the future.
(Potty Jag har smör i min rumpspringa, Tue 30 Jun 2009, 11:17, Reply)

Yes - makes sense
I know that the shuttle dumps the equivalent of an olympic sized swimming pool in a very short time on takeoff.
(Bicycle Repairman "you're also a bit of a wanker", Tue 30 Jun 2009, 11:20, Reply)