And, this is purely a subjective opinion but the rockets just don't seem large enough to hold enough fuel to maintain their engine burn long enough to rise 50-60 miles or whatever is theoretically required to do what they're supposed to do. I mean, when I see that flame pouring out of that skinny rocket it always looks to me like the fuel is going to be used up after only a few minutes at most. And, going as slowly as they seem to be going, I just don't see how it's going to make it more than a few miles up, if that
Know what you mean Lux.
Researching various aspects of.. ‘Does rocketry work in a vacuum?’
I looked into the stats of the most talked about rocket engine of all time, the mighty, awesome, most powerful ever; Saturn F1.
Here’s a famous fountain in Geneva that I’ve seen on a couple of occasions which makes for an extremely impressive sight..
The ‘Jet d’Eau’ squirts a half ton a second out the nozzle http://en.wikipedia.org/wiki/Jet_d'Eau
via dual .5 MW electric pumps that supports (at any given moment) a total of approximately 7 tons of water in the air.
But that’s nothing, in fact a child's water pistol in comparison to the F1 since we are led to believe that 2,169 tons of fuel / oxidiser is consumed within 150 seconds http://en.wikipedia.org/wiki/Saturn_V
which equals 14.46 tons per second, divided by the 5 engines and you get the equivalent of 5.784 Jet d’ Eau’s each! Flippin’ flamin’ ‘eck!!!.
To elaborate a little further, here’s an image of Rocketdyne’s F1 injector head..
..a glorified manhole cover, just short of 1 meter in diameter with small holes drilled through it to allow those 5.784 Jet d’Eua’s worth of fuel and LOX to escape every second. But not unhindered may I add, since the expanding force of the ignited fuel within the main combustion chamber was reckoned to be 70 bar (1015 psi...check the Wiki link). Crickey! What sort of pump is going to deliver that kind of volume under that kind of counter pressure? Well, that would be this little guy...
I can’t find any dimensions, but from photos of the whole F1 assembly I’d say that this remarkable piece of kit was no larger than a standard set of bag-pipes.
As best I understand it, the gas generator is basically a little rocket utilised to feed a larger rocket. Fuel and oxidizer are fed into the bomb shaped combustion chamber and ignited which produces high pressure gas which is then piped into a turbine assembly which in turn drives the propellant from the main tanks via pumps through Rocketdyne’s giant shower head of an injector plate to be burnt with a resulting pressure of 70 bar. Here’s a typical schematic...
The story goes that this ‘pocket rocket’ developed some 50,000 horse power or just over 37 mega watts. To be sure, that’s 37 times the combined effort of the Jet d’Eau’s pumps seen here..
..or 37 of these comparatively cumbersome V16 1MW diesel gen’ sets..
Amazing! Truly the nuke bomb equivalent of engines
Also, I think I might be a little concerned about keeping our pocket rocket cool. Wiki says that the fuel / Oxygen mix was fed ‘rich’ and this somehow negates the need for any kind of fluid cooling or even air vanes...yup, just squirt in your propellant, light her up and you’re good to go. No screwing about with fans, radiators, water pumps or any of that daft nonsense that you’d find on your average family motor producing, say, 1 / 500th of the power.
Just one other thing that I’m not too clear about. As said, if you have a feed system shoving propellant into a combustion chamber, that system must operate at a higher pressure than the combustion chamber itself as 1 bar certainly isn’t going to move into 2 bar. Fine, I guess if you’ve got 50,000 hp at your disposal but what’s feeding the ‘pocket rocket’? Itself? Or are the fuel and Oxygen tanks permanently pressurised (no matter how full / empty) way above 70 bar?