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Sep 27, 2016, 09:29 PM
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Generation millenial's Kennedy moment


Must concede, the 1st time the BFR appeared on the monitor was a bit of a letdown. It seemed too unreal to ever achieve. It went against everything in the Andy Weir book. The size was completely nonsensical. Just when the ship was supposed to stop at an orbiting outpost, the ship kept going, all the way from the launch pad to Mars. Was this nonsense what Musk worked on for the last 2 years?


The internet expected something more realistic, a 3 cored rocket of incrementally more power than the Saturn V, but not 4x more powerful. Things went downhill when the 42 engines all randomly stuffed under the booster appeared. It looked more like throwing the kitchen sink at a problem than rational calculations.


Then Iron Man showed up with a moustache resembling Howard Hughes. He assuaged some fears by stating the video was based on CAD models & there was enough room for BFR facilities to coexist with the current Falcon 9 facilities on LC-39. He already built a full size oxygen tank for the 2nd stage, in addition to firing an engine which seemed to be the full size engine. We all hope today's speech goes down as a Kennedy moment, where we all remember where we were when it happened & quote the lines for all eternity.


The spartan black & white graphics brought back memories of the Saturn V diagrams from the good old days. That made it look a little more legit. Nothing that detailed was released for the Falcon 9. Delta IV & Atlas V diagrams were always dumbed down.


Kennedy's speech only became immortal because we actually made it to the moon. Sadly, the modern audience was extremely poorly educated by comparison. The speech was given in Mexico & they only wanted to know if Mexicans were going to be hired. It sort of highlighted the education gap between Mexico & the rest of the world.


1 glaring issue was achieving a propulsive landing after 100 days in space, with supercooled propellants. Was the spaceship going to have a way of refrigerating the propellants for 100 days? If the refrigerator went out, the passengers would die.


The other question was whether the Raptor was being developed for any other purpose. We know a vacuum version was developed for the air force, but the sea level version is purely a human colonization effort. No-one in the uneducated audience asked these questions.


The Raptor would have a chamber pressure of 4350psi or a bit more than the RS-25 rating of 3000psi. Such high pressure would allow it to make more power with a much smaller throat & nozzle than the RS-25, as long as the expansion ratio was big enough. The highest pressure these days is in the RD-180 at 3800psi, so another few hundred is probably reasonable without resorting to kryptonite.


Fabrication would rely heavily on the same revolutionary carbon fiber tanks that doomed the X-33 program. As it was with the X-33, the carbon fiber tanks were again the 1 essential enabler preventing everything from falling over. It was again built on hope that more progress would be made someday. Materials are the limit to all progress, from building robot dogs to spaceships.


Then, there was the price. It was most impressive, compared to the amount NASA spends on absolutely nothing. He could have quoted a much higher price based on the fact that the booster was reusable. The price of a cruise ship comes across as reasonable for a reusable spaceship & those are in the billions. Once it becomes reusable, the maximum cost of a rocket becomes unlimited.


Despite deferring any work on reusing the Falcon 9 2nd stage to the BFR, he's only putting 5% of the company into it. All the rest is on fixing the existing problems with Falcon 9 or manufacturing it. Considering what he did with 5%, it shows how much human labor is required to manetain even the simplest space program.


Despite the money issue & refrigerating the propellants for 100 days, some bits make logical sense. If the 2nd stage of all modern rockets goes all the way to orbit with the payload, you might as well integrate it with the payload & refuel it in orbit. If the base of the rocket is wide enough, it doesn't need landing legs. He copied Lockheed's tetris shaped service tower, though it probably won't survive a hurricane. The lifespan of the spaceship is taken into account & no mass is put into space which isn't essential to all stages of the mission. Andy Wier will no doubt have some comments on the design, his idea of a space based component that never lands having been completely rejected.


If the promises are to believed, the human race would be better off if NASA put all the SLS money into the BFR, but this won't happen. NASA could also fund the carbon fiber research & engine research, but this won't happen either. H-Rod is going to keep the SLS going because of the labor unions & pension plans it's funding. Other money will go to doctor unions & teacher unions.


Numerically, the lion kingdom has a chance of dying on Mars. It wouldn't take having kids who would then leave Earth. It could all happen in the last lion kingdom generation. Having lived over 70 years, there wouldn't be much fear of dying in space. The problem is the colony is going to need to be very industrious to survive. They won't take really old lions who are going to fall over in a few years or who are no longer self sufficient. There's still upward pressure on the age because these people have the least to lose if they die.


If income & social order was different & the lion kingdom reproduced for the sole purpose of having a kid go to Mars, how would the conversation start? "So what do you think of Mars?"


There are enough people in the world of sufficient age & desire to drive the price well over $1 million for a trip to a permanent colony. Bezos, Carmack, & Branson couldn't charge a lot of money because they only offered a brief stay in space. Offering a permanent or long duration home in space is another game.


The process would certainly be a lottery & make enough money to be commercially successful. Of all the visions of what LC-39 would become, 1 of them could be the start of commercially successful trips to Mars. What would the Neil Armstrong standing on LC-39 in 1969 have thought if he knew what was to become of it?
Last edited by Jack Crossfire; Sep 28, 2016 at 12:17 PM.
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