> Hi Paul & Group - and happy new year!
 >
 > I run into this when browsed TC images on google:
 > http://www.enginehistory.org/vicenzi.htm
 > probably this has been posted before, but i have forgot ;)
 >
 > And one semi-ot thing that i cannot understand. I think that
 > some of you
 > have wrestled with rocket boosters before...
 > www.spacex.com - that's Elon Musk's (paypal founder) rocket
 > company that
 > is going to "revolutionize the space access".
 >
 > There's some figures on their specs that i don't understand.
 > Namely, how can you get 12 tons stuff to low earth orbit with a rocket
 > with specs like this:
 > Launch mass: 337 000 kg, 1 stage Isp 275, 2 stage isp 304.
 >
 > My spreadsheet gives only 3.5 tons max with these 2 stages. I would
 > suspect my undergraduate abilities, but my sheet agrees
 > perfectly with
 > Saturn IB specs on http://www.astronautix.com/lvs/saturni.htm - just
 > spacex falcon 9 specs seem to be "a bit" off...
 >
 > Is there Unobtainium somewhere?
 > You know that handy stuff that is used on government contracts, that
 > when exposed to daylight decomposes instantly to Costoverrunium and
 > Specdowngradium on arbitrary ratios...
 >
 > Otherwise, Mr. Musk seems to be very inventive and reasonable person.
 > Maybe we can talk him to support our compound  mission?
 > He seems to live almost on your neck of woods, Paul - How about
 > paying a
 > visit? :D
 >
 > Cheers,
 >
 > Petri
 >
 > Hi Petri and Paul,

More on this web site.  3 PDF files available on this link (click on
more) and the two files on bottom of page.
http://www.enginehistory.org/wright_aero.htm

Marc Joseph

Finally, i had time to have a look of their TC paper - this is just
wonderful! Look at the attached image...

And the speed of exhaust gases entering the TC turbine was really 2200
fps, like i suspected :) :)

btw: about that spacex booster: they do it by making _very_ lightweight
booster structures. If interested, have a look at this discussion: >
http://forum.nasaspaceflight.com/index.php?topic=12863.0

Cheers,

Petri