This page:
http://web.syr.edu/~smdemar/rocketdrag.html

Contains a diagram just above the bibliography which seems to
indicate that a transition is no where near as good as a front
loaded egg lofter shape. Does this seem right?

-- 

Howard Smith
"If you woke up breathing, congratulations!  You've got another chance."

http://www.fairdene.com/pars/
--UKRA, EARS, PARS

On 17 Apr, 08:34, Purley Amateur Rocketry Society
 wrote:
> This page:http://web.syr.edu/~smdemar/rocketdrag.html
>
> Contains a diagram just above the bibliography which seems to
> indicate that a transition is no where near as good as a front
> loaded egg lofter shape. Does this seem right?

Without a detailed knowledge of aerodynamics, I can't comment on the
validity of the results, but the wind-tunnel results presented seem to
be well-researched. Perhaps someone more knowledgeable can shed more
light on the reasons for this.

What is worth remembering is that while the egg-lofter shape may have
a significantly lower Cd, it also has a large frontal area. If you
look at the measured drag figures, they are significantly higher
(approx. doubled) compared to the 'transistion' rocket. The Cd may be
halved, but the area is almost quadrupled. Bearing this in mind, I'm
not sure I believe the simulated results presented, which suggest
'rocket 12' would reach the highest altitude, despite having the
highest drag figures. Perhaps there's some optimal mass effects at
work too.

The surface finish results are interesting, and show a useful
reduction in Cd for a polished and waxed finish. Same goes for launch
lug deletion.

Niall