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Old April 11th 17, 04:22 AM posted to sci.space.policy
William Mook[_2_]
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Default Reusable Laser Launcher

On Tuesday, April 11, 2017 at 9:38:05 AM UTC+12, Serg io wrote:
On 4/10/2017 4:14 PM, Robert Clark wrote:
The U.S. military is making progress in high power lasers. The Navy
expects to field a ship-born 150 kW laser:

US Navy Prepares To Fire 150-Kilowatt Laser Gun From Sea Vessels.
https://www.youtube.com/watch?v=5fr0SM8vNk8

And the Army expects to field a laser carried by trucks at 60 kW power:

US Army gets world record-setting 60-kW laser | Latest News Updates Today.
https://www.youtube.com/watch?v=L9AC1njoP5o

Assuming linear scaling,


not linear at all, dude !


Power is linear to thrust at non optical vehicle speeds.

Power is less than linear at near optical speeds. Though recycling photons through a low loss path can multiply power for a photonics thruster to mitigate this high speed effect if the materials are up to it.

More here

http://ykbcorp.com/downloads/Bae_pho...ulation..pd f

Leik Myrabo in the 1990s experimented with lasers that fire repeatedly up to 250 MW laser energy at White Sands to fly sub scale vehicles up to 400 foot altitude.

http://www.globalsecurity.org/space/systems/miracl.htm

There are lasers over 1,000 MW continuous power that are in the works. These produce far higher peak power over very short time periods as well up to 2 quadrillion watts!

http://onlinelibrary.wiley.com/store...set/37_ftp.pdf

http://www.dailymail.co.uk/sciencete...ful-laser.html

Using a diode laser, at 35 kW/kg and $0.10 per peak watt, a 50 MW system weighs 1.43 metric tons and cost $5 million. A 10 GW system weighs 286 metric tons and costs $1,000 million. The first puts up 330 pounds into LEO. The second 66,000 pounds per launch.

So, quite linear.

With one launch every two hours, and a 12 minute boost - a 1 GW power plant, costing between $500 million (for coal) to $5,500 million (for nuclear) is required to power the 10 GW laser. About twice the size of the requirements of this plant

https://en.wikipedia.org/wiki/Tiwai_...minium_Smelter

A $1,500 million battery pack to store the required energy and discharge it over 12 minutes, every two hours, is also required for the larger system.

The smaller system can use a portable generator on a ship, or a portable aeroderived generator, or tie into the grid directly, to power the laser on demand - and fire continuous at the lower power rating.

About 1/10th the Tiwai Point Smelter. Or the size of a shopping mall at peak power.

A 50 MW diode laser firing continuously, with a 2 hour recycle time for launch vehicle, and 10 active vehicles, using a dozen active flight articles, for insurance, at $1 million each, we have for less than $20 million the ability to put up 330 pounds x 5 = 1,650 pounds per hour 24/7 - that is 39,600 pounds per day, 14,463,900 pounds per year - at a cost of $78.6 million per year. $3.03 per pound. The value is obviously far greater! More like $1,000 per pound!

The CAPEX is if far less than conventional rockets as well! The system is also quite flexible for payloads that are subdivided into 330 pound increments and self assemble on orbit.

https://wyss.harvard.edu/a-self-orga...d-robot-swarm/

With an average passenger weight of 187 pounds, and another 100 pounds for suit and supplies, people are easily and cheaply put into space for less than $300,000 pounds at the rate of 5 per hour using a single launcher.

Or a network of communications satellites that provide global wireless broadband internet services directly to and from people on the ground without any special receivers or transmitters.

http://fortune.com/2016/11/17/spacex...obal-internet/

This allows the launch provider to capture a portion of the $2 trillion telecommunications market and grow that market, for a fraction of what is earned form the sale of services each year.

This revenue, over 100x NASA's budget, is then used to expand one's capacity, launching larger payloads, and larger numbers of payloads, to provide solar power beamed from space by laser.

This captures a portion of the $4 trillion energy market and grow that market as well under similar terms.