wdw wrote:
I've enjoyed following this discussion. As you all worked out, the
figure I gave in the book is relative to the ground. Later in the same
chapter, I introduce the reader to the idea of stating speed using
space-fixed as opposed to Earth-fixed reference.

Hope I didn't confuse too many folk.

In case I'm lucky enough to get a second edition for the book, I'm
always happy to entertain suggestions for improving the text. I have a
website for the book:

www.hafttm.com

and there is a list there of points arising.

Cheers

David Woods
Author: How Apollo Flew to the Moon


Perhaps you can explain the small dip in the curve given for Vs
in Figure 1 on page 2 in the NASA Tech Note linked to below:

http://www.klabs.org/history/reports...1970023342.pdf

In the curve for Vs it appears it actually is *reduced* for
approx 25 seconds after launch before rising above its initial
value at s=0. We're speculating its due to early rocket motion
due to first stage engine gimbals?

David Spain