On Thu, 11 Sep 2003 18:06:15 +0100, Ian Woollard <[EMAIL PROTECTED]> wrote:
>On the other side of the coin, the thrust:weight ratio is not that bad, >you only need enough thrust to hold an altitude for a couple of hundred >kilometers, and you may even be able to use it on the way up too (for a >small amount of the flight envelope), they have no moving parts, they're >more reliable, need much less maintenance, and are cheaper to build/buy >than a turbojet. > >I'm not saying they're theoretically as good as a turbojet; but quite a >bit of the cost of a launch vehicle is in the purchase of the said >launch vehicle and jets cost a whole lot more. Fuel is the cheap bit. >I'd bet dollars to donuts that it's more cost effective in this case. I'll take that bet. There are no commercially produced ramjet engines. There are dozens of commercially produced turbojet/turbofan engines. I'm positive a turbine-based RTLS launch vehicle system could be produced for less money than a ram-based system of equal performance. I'd also bet, though a smaller amount, that you couldn't make a case that either one is competitive with the equivalent existing ELV. -R -- Son: Dad, I have a question about women. Suppose I Dagwood: Apologize anyway. Son: Yeah, that's about what I figured Dagwood: It saves time _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
