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My Two Bits Ain't Worth 1E-15cents
Okay, I just realized something about my two bits worth. They ain't worth
squat. I ran the numbers for 11GW/ton/s on my portable RPB decelerator idea
and came back to the same problem that Kelly has with his Explorer design.
We need too stinkin much power.
Assuming 11GW/ton/s to accelerate a measly .036 g and using a De + 3He
reaction that yields 3.606E14 Watts/kg and applying that over the time it
takes to accelerate to 1/3c at .036 g the numbers got supremely ugly in
terms of fusion fuel weight.
Back to the drawing board.
Perhaps the launcher idea could still work with the Explorer design. What
we have to do turn the Asimov into its own fuel launcher. Have the ship
rail gun launch most to all of the ship's reaction mass behind it. The
particles will have to be at least fast enough to cover a .25 ly track in
the time it takes to cruise to Tau Ceti (if we could keep the track
together over that amount of time and distance, would it be easier to launch
the track from Earth?).
As the Asimov begins its deceleration phase, the relatively faster moving
reaction mass track slams back into the ship. We ionize the RM and run it
through the accelerator for thrust just as if it were interstellar medium.
A downside to this idea is the drag caused by hitting the really fast
particles at the end of the deceleration run. Also there are going to be
serious power cost to launch the track.
Kevin's 11.5 ly long power cord is looking better all the time.
Since we'll have to carry so much reaction mass for the launch track, I
suggest we use the E18W we have planned to mag-sail launch the ship. So I
guess we launch the track via the ion accelerator using it as a rail gun if
that is possible.
Someone else had better run the numbers on the drag and power needs. That
is if anyone thinks this has a chance of working. If not, please show me
the error of my ways.