Comments by "ke6gwf - Ben Blackburn" (@ke6gwf) on "Primal Space" channel.

@nopenope9023 , you need to get out more man! lol Crew Dragon is the SpaceX capsule at the ISS right now, designed to carry crew instead of just cargo. The Dragon capsule is the one designed for the Falcon rocket, and has the cargo and now crew versions.
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@lsucowboy the trucks that haul these loads don't carry most of the weight of the load, that's why the trailers have so many axles. Now where the Tesla semi will have problems is going uphill, because these heavy haul trucks have super heavy duty axles and such to handle the torque needed to pull all that weight, and while the Tesla could handle the vertical weight, the axles and gearbox are not designed for the kind of pull and torque that heavy haul trucks do. So even though the Tesla might have more power, I would not want to put this heavy of a load behind it. Plus, it would use the battery so fast on the hills lol
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@gregistopal you might want to check your facts. All electric vehicles that I know of, and definitely the Tesla, have a gear box. Otherwise you would have to have the wheel attached directly to the end of the motor shaft, and motors don't have that much torque. I think the Tesla has something like a 9:1 gear ratio or something like that.
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@earlpottinger671 Hi, I am a truck driver, with heavy haul experience! Nice to meet you. Have you driven truck much? Even with a max gross load, there are many hills that I go down in the western US mountains where I have to keep the Jake off most of the time because it slows me below my desired speed, even on low. And on the same grade going the other way I am burning considerable fuel. It's only on the steep grades that you get good regen, because unlike a car, a semi has a lot of air resistance and friction that affects it up hill or down, and is enough to slow it down on a downgrade rather than let it roll away. So if you have a steep climb up one side of a mountain, and then a gradual decline on the other side, you get very little regen, if any. And there's lots of mountains between Hawthorne and Texas, high desert, etc, that will have these types of intermediate grades. And remember, after climbing up from Hawthorne at sea level to the high desert at 3 or 4 k feet, you then stay at the higher elevation as it gradually falls back down. So you don't get that climb energy back, at least not within hundreds of hilly miles.
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Joe Chang , once you get out of the atmosphere, you use mass ejection to reach the desired speed, and then you coast. Since it is a vacuum, there is nothing to slow you down, so you can travel as far as you want. That's why the space station can keep orbiting at 17,000 mph, because there is nothing to slow it down. You are correct that in the atmosphere things are limited by air resistance and need constant fuel consumption just to keep moving, but even things like icbm missiles work by getting out of the atmosphere, orbiting around to the right location, and then reentering the atmosphere.
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@naufalfarras1556 , but no one else can handle the larger payloads either, so someone is going to have to design a way to do it, and since SpaceX is so much cheaper to begin with, they can build a custom fairning or nose cone and still be cheaper than anyone else. So if it is light enough for FH, just larger than the fairing, they change the fairing. But that's still a small market, with no loads like that currently. And then we have the BFR on the way, which will be able to handle those loads lol
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@Hallahanify with some loads, they just unhitch from the trailer and go into the truck stop. The larger loads can only travel at night usually, and so it's not uncommon to drop it in a safe spot, and bobtail to the motel, and get fuel along the way. Also, heavy haul trucks often have giant fuel tanks, and so may be able to make the trip on one tank. They need the extra weight to give them traction anyway. Otherwise, they will just have a support truck with a transfer tank in the back, and when they stop at night they top it up. If they had a Megacharger network built, it would be possible to drop the trailer and go charge, but unlike the diesel trucks, they can't just put bigger tanks on and be able to go coast to coast on a tank, so yes, range is quite limited in comparison. Of course, if SpaceX was going to be hauling from Hawthorne to Texas and then to Florida with the Semi, they could install Megachargers at appropriate distances along that route, large enough to pull into and charge. It could be part of the eventual buildout of the network, and be an example to potential customers of the capability. But diesel certainly is easier to deal with in heavy haul! Lol
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Nasa has to spread the manufacturing out to get the support of many different politicians in many districts, that's why the Atlas was so spread out. SpaceX may have that in mind too, but mostly it is practical. Elon picked Hawthorne because he had an employee base, with a lot of engineers and tech people and aerospace people already in the So Cal area, and being an attractive area for people to move to for the job. I would guess that McGregor Texas was chosen for cheap land, and on the way to Florida. And Boca Chica is probably cheap land as well.
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You make a decent video on the subject, but please research the technical aspects a little bit more before acting like an expert while giving very bad information. For instance, the Sabatier process takes water, and co2, and creates oxygen and methane. That is the way they plan to get methane on Mars, because the methane in the atmosphere is too low a concentration to easily extract, but co2 is abundant, and water is accessible. It's also how they plan to produce the Starship fuel on the earth, again using water and atmospheric co2 and electricity to produce methane and oxygen (the oxygen comes from the water and the co2, and the hydrogen from the water combines with the carbon from the co2 to form methane) In addition, the crane by the well site was just being assembled there, and long ago was transported to the launch site where it is being used. It was never intended for use at the wells, they just needed a large open area to assemble it. So long term, SpaceX won't be using natural gas, and the method where you get oxygen from water is called electrolysis, while the diagram you showed on the screen was producing methane and oxygen,.
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Joe Chang , an icbm can reach anywhere on the globe, since it goes into orbit, thus has unlimited range. Short and medium range ballistic missles etc never leave the atmosphere, so they are limited by how much fuel they carry, because they can't just coast in the vacuum of space. Do you see how things change when you get out of the atmosphere and no longer have air resistance?
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@naufalfarras1556 , for large bulky items such as ISS modules, you either make a custom shroud around them for launch and include it as part of the payload rather than part of the rocket, or you build the module to be able to handle launch, and just put a nose cone on it. Compared to the complexity of building the rocket, building a custom nose cone or fairing is peanuts. The existing fairing is the one designed for Falcon 9, based on the average size of most of the payloads, so they have never even built one for the Heavy, because so far they haven't needed anything larger. But offer them a payload too large to fit in the standard fairing, and see how quickly they can modify it to fit or design a new one.
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Joe Chang , what do you mean that we can't measure space craft speed yet? Considering that we can measure it in many ways in many reference systems, I don't know what you are talking about.
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@naufalfarras1556 , there are currently no options to fly anything much larger than what the Falcon can carry, so except for that small market of heavy and slightly bulky satellites, anything larger is going have to have those things figured out anyway. There is currently no system with the capability of the Shuttle Bay, so anything that would be that size is going to need a custom solution, and SpaceX is the fastest option to make it happen. And if someone is going to all the work and planning to build a giant module going to space, running some aerodynamic calculations and planning a custom fairing is well established rocket science. And with the ability that Falcon has for thrust vectoring and throttle control and such, it can handle minor aerodynamic problems easier than a solid rocket system etc
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Joe Chang , there are many ways to measure spacecraft speed, from radar, to lasers, to Astral navigation (measuring the angles to stars), and in the vicinity of the earth, GPS provides accurate speed reference. I can go into detail on any one of those methods if you want.
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Joe Chang , when they are closer to earth they have a military grade GPS receiver that measures the time radio signals take to travel between the GPS satellites and the rocket and calculates position and speed, just like your phone, but much more accurate. If it is headed away from earth, they use a radar transponder, and send a signal from earth and measure how long it takes to return, and then calculate speed from rate of change. If they want to be really precise, they can put a prism reflector on the rocket and shoot a pulsed laser beam at it and measure the time it takes to reflect back. They can measure to the accuracy of a photon this way. When a rocket is in visual range, just launched, or like a military short range rocket, they often use high speed cameras and measure how far it moved per frame. They can also use multiple tracking cameras like you see for nasa launches, and by feeding the exact angles of several cameras into a computer, they can triangulate the exact position, and calculate the speed. And while a rocket is still in the atmosphere, they just use a regular air speed indicator like a plane would use. So there are many ways to measure a rocket's speed, and most of them are more accurate than your car's speedometer!
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Joe Chang , GPS, radar, measuring time of travel of radio waves to the ship, laser reflectometry, measuring speed with high speed camera, uhh, did I miss any?
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@earlpottinger671 what about when you don't have a downhill on the other side? Lots of places have a steep climb to a plateu or high desert, or a long gentle slope down the other side. You only get the energy back when the downgrade is steep enough to use full regenerative braking. If it's gentle and friction and air resistance is holding it back, you may not get any energy back. Look at something like Donner Pass. If you are climbing out of the Bay Area to Reno, you have like 50 miles of constant up grade going from sea level to the summit at 7k feet, and then drops down to Reno on the other side, which is at 4.5k feet. So going to Reno, you lose half your climb distance.
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You make a decent video on the subject, but please research the technical aspects a little bit more before acting like an expert while giving very bad information. For instance, the Sabatier process takes water, and co2, and creates oxygen and methane. That is the way they plan to get methane on Mars, because the methane in the atmosphere is too low a concentration to easily extract, but co2 is abundant, and water is accessible. It's also how they plan to produce the Starship fuel on the earth, again using water and atmospheric co2 and electricity to produce methane and oxygen (the oxygen comes from the water and the co2, and the hydrogen from the water combines with the carbon from the co2 to form methane) In addition, the crane by the well site was just being assembled there, and long ago was transported to the launch site where it is being used. It was never intended for use at the wells, they just needed a large open area to assemble it. So long term, SpaceX won't be using natural gas, and the method where you get oxygen from water is called electrolysis, while the diagram you showed on the screen was producing methane and oxygen,.
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