Re: Large rocket engines cannot be reusable


Andrew Nowicki wrote:
> Henry Spencer wrote:
>
> > This would surprise the people who built the F-1, whose
> > specs demanded that it be reliably capable of 20 starts
> > and a total run time exceeding half an hour...
>
> That is how long you can run a car engine after
> you have drained its oil...

Go on then-- try it. 30min not a chance and thats a plain car. High
perfomance engines like Nascar or F1 would not even last 10's of
seconds.

> Big things are dinosaurs.

this really small engine thing lacks substance. I have made small
rocket engines for amature rockets, and guess what- its not at all easy
and high perfomance is still next to imposable untill you size them up
a bit.

The truth is there are scaling laws, and relabity issues as well as
cost issues that means there is some kind of "optimal size". Its not
really really big but then its not really small either.

Greg

.

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