[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: starship-design: stale mail



Your mail to:  "Michael K. Heney" <mheney@mach-25.com>
> with subject:  Re: Virtual Beanstalk -- Numbers, numbers, who's got the
> numbers?
> sent on:  Sun, 08 Aug 1999 21:42:13 -0600 is being returned to you.
> It sat unread in the mailbox beyond NetZero's 6 month limit.
>
> Undelivered Ideas
>
> > >     Sorry for saying you were negative. I know you were just trying to
> > > put a practical spin on my $10 orbital goal and that you want cheap
> > > access to space as much as I do.
>
> Here are some round about numbers for my view on the lowest cost.
> http://www.rotaryrocket.com/tec/rotonv.html  Rotory rocket.
>                              Mass fully loaded 180,000 kg
>                              Pay load            3,200 kg
>                          cost per playload  $2,200 kg
>                              fuel/payload       56:1 
>
> http://solar.rtd.utk.edu/%7Emwade/props/loxosene.htm
>                          lox/Kerosene ratio 2.5
>                          40 kg lox
>                          16 kg fuel   for each kq of payload.
>                         
>                          cost 1980 lox kg    $ .08
>                                    fuel kg   $ .20
>                          assuming 3 x increase for 2010 then ( my guess )
>                                lox  .24
>                                fuel .60
>                               lox  $9.60
>                                               fuel $9.60
>                           rounding up $19.20 per kg of payload fuel costs.
>                           tricky part assume a running cost 30% of the fuel
>
> Mininum cost                      $   25 per kg   $12.5 per lbm
> RLV Current cost                  $2,200 per kg
> Mature  cost ( guess )                        $   50 per kg   $25.00 per lbm
>
> So here are my numbers. I can see why NASA and the military have never
> developed  RLV's look how much you can rip off the tax payer.

The big issue is the service costs.  Shuttles fuel costs are only tens of dollars a LB, but the real costs are thousands per.  The big thing needed is improving the servicability and amount of trafic.

Oh as a nit, fuel and LOx costs have been droping, not rising, for years.

No idea why this sat in a server for months.

Kelly