Am 18.10.2011 10:14, schrieb Scout:
"Thomas Heger" wrote in message
...
Am 17.10.2011 07:01, schrieb Scout:
..
For Earth orbit you need much faster flight than you would need to
stay in orbit around the moon, but nevertheless it is quite fast. On
Earth it took a Saturn V rocket, to lift the craft into orbit. On the
Moon it would take less fuel, but way more, than the few gallons, they
had in the lander.
Ok, let's see your math.
I mean if you know they needed more, then clearly you have calculated
all this out and know exactly how much they would need and whether they
could have that much on the lander.
So let's see your work.
---- Insert mathematical proof here.
Here I will even aid you with the specifications for the mass, amount of
fuel, type of fuel, specific impulse, thrust provided, available
delta-V, and so on.
http://en.wikipedia.org/wiki/Apollo_...Specifications
Well, I'm a little too lazy, but a rough calculation is possible:
There is the Tsiolkovsky rocket equation
velocity_final=v_exhaust* ln(mass_start/mass_finish)
V_end= 2200 m/s * ln (4547 kg/(4547-2353) kg)
that is :
v_end approx. 1603 m/s
this is an estimated calculation without gravity.
the final velocity is reduced by
delta v = g_moon * (time of engine running)
Don't know that number (time_ engine)
Maybe 100 seconds (???)
makes:
delta v = 1.6 m/sē*100 s=160 m/s
What gives a rough estimate for the final velocity of the landers
ascending stage of
v_end = 1440 m/s.
Now the orbital velocity had to be compared. But I don't have the data
and actually I'm too lazy to find them out. But usual orbits should be
a little less than escape velocity, what is
v_orbit_escape = 2380 m/s.
V_end is a rough estimate ('thumb times pi'). For better calculations
someone with more experience in rocket science is needed.
I cannot even tell you, if the ascent stage is fast enough or not. But
my intuition tells me, it is not.
IOW, you don't know what the hell you're talking about, and you're too
lazy to do the work needed to find out if what you think actually has
merit or is simply bat **** crazy.
I haven't claimed to be a rocket scientist. I'm totally happy with an
rough estimate. I could do it better, for sure, but do not want.
The reason is, that to figure this out is not my business - as I have
written.
You gave me that link and demanded to tell, what's wrong with the Apollo
program. I made a few comments to the picture on that page.
Than you wanted a mathematical proof, that the lander could not reach
the orbiter with the fuel in the ascent stage.
I gave you a short version and explained, that better calculations are
certainly possible, but I don't want to provide them. You could do that,
if you like or ask somebody. It is not THAT difficult. (Maybe there are
simulators already or Mathematica packages. )
It is certainly more interesting for American people than for me as a
German. The reason is, that the Apollo program would allow to
understand, how your government actually acts.
Greetings from Berlin
TH