Here's a quick video demonstrating the technology, using lasers to lift a small prototype several meters, back in, what I believe is the 90s: https://www.youtube.com/watch?v=i81f3LifpWY
...Is that ablating the ceiling as it drifts off-beam?
I'll always link this whenever it comes up. Highly recommended if you haven't read it.
Numerous startups are tackling the power beaming issue with relatively short timelines and in some cases a lot of funding, but the scale of what's actually been publicly demonstrated with lasers is unimpressive...
"Roundtrip Interstellar Travel Using Laser-Pushed Lightsails"
https://ia800108.us.archive.org/view_archive.php?archive=/24...
It's not generally understood just how remarkable rocket engines are. They're the most efficient heat engines we can make. They are orders of magnitude better than other heat engines in power/mass and power/$. Their Isp is fine for launch, particularly for the first stage where most of the propellant is consumed.
Oh that's all?
And you're going to avoid having to spend $600 billion on the equivalent of four Ōi Nuclear Power Plants by wishing a practically impossible flywheel proposed as an exercise in engineering optimism over 30 years ago into existence?
Sweet!
To put less than the payload of a single Falcon Heavy into space?
Why build one when you can have two at twice the price!
edit: forgot the 90s were 30 years ago.....
I’ve been wondering about this actually. (Please keep an open mind if responding)
In theory if we used a high enough voltage. Possibly in the megavolt range we could have a very lightweight wire. And if we could turn that directly into heat on the rocket without even needed equipment to step it down.
I don’t see why we couldn’t have long wires. At least 20 miles and use it as a low speed first stage.
A couple notes. Running your numbers through Ai it looks like it would weigh about one ton per km of wire. And possibly much less if you’re ok with more power loss and high wire heating. Since this is a short term use that might be fine.
But on top of that the extreme amount of power is only needed because we’re trying to get up to speed as fast as possible to minimize gravity loss.
If we’re not carrying our fuel for the first stage it’s conceivable we only need enough power to hover the unit and gradually get it up to top speed.
I know it’s still a far out idea but might be workable from first principles.
The mistake I made then was thinking fuel was expensive, so I assumed similar performance to existing rockets as if I was using it to superheat cheap water to the combustion temperature of hydrogen-oxygen — the problem with this being that it's pumping the equivalent of the entire electrical power demand of the United Kingdom into an engine the size of a truck for 6 minutes without it exploding.
(Similarly, it's possible to push against Earth's magnetic field but if you use copper the resistive losses will vaporise you launch vehicle. And you can make a much stronger artificial field on the ground, but the way magnetic fields reduce with distance means the current loop on the ground has to be significantly larger than CERN's LHC).
I'm no laser expert, but this doesn't seem right to me.
https://spectrum.ieee.org/fiber-lasers-mean-ray-guns-are-com...
The technique appears to involve multiple lasers of slightly different wavelength; this allows the beams to be combined and to not interfere with each other.
https://www.exail.com/photonics/spectral-beam-combining
https://www.rp-photonics.com/beam_combining.html
https://agiltron.com/category/fiber-optical-splitter-coupler...
This book outlined a whole space colonization effort from soup to nuts: