Comments by "ke6gwf - Ben Blackburn" (@ke6gwf) on "Scott Manley"
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Some observations from someone who enjoys working with metal.
The base section is completely structural. It is using welded heavy wall stainless steel pipe for a bulletproof internal support frame and landing legs, heavy enough to withstand "slight miscalculations" on the suicide burns and punch holes in the concrete if needed.
This looks like it was designed by an engineer familiar with building bridges and roller coasters and other such durable structures, and I see signs of very good workmanship in the welds and little details like the contoured gusset plates and such.
It really looks like it's designed to support a bridge rather than fly. But considering that Elon probably wants something close to actual weight, overbuilding this is not a problem, and makes it more likely to survive heavy grasshopper testing without needing repairs. (landing pad is more likely to need repairs lol)
The shell of the base section is heavy gauge SS as well, and was all bent in large probably CNC plate rolls making perfect curves that fit and weld together. And it is heavy enough not to distort from the welding.
I assume that this will all be polished up to a mirror finish, and was built by a structural engineering team.
The upper sections are built totally different, and I suspect by a different team or company.
They seem to be an open framework with thin sheet metal panels fastened over it.
It makes sense that it is a water tank company, because they would have experience doing such things.
Now the difference is that they normally aren't trying to do compound shapes with thin sheets on water tanks, and it is nearly impossible to do it with flat sheets without lots of wrinkles and divots, just like of you put a sheet of paper over a basketball.
They may have some trick to use heat to stretch the sheet metal and smooth it out after the structure is finished, it's pretty much black magic, but it is used by good sheet metal workers, so I say wait a little while and see what they are able to do.
I also will not be surprised if the company that bid to do it had never done anything quite like this before, and are finding that they are fighting the metal, and it is winning lol
So this may turn out to be a total failure on their part of being able to get a good looking result.
Elon may be fuming about how ugly it is looking as we speak.
On the other hand, as long as it is all attached properly, it is totally flyable as a grasshopper, and once the polishing is done it will be hard to see the surface shape.
So it is possible that Elon decided he wanted something of the right size and shape and shiny to be in the air asap, and so is using his preferred fail fast prototyping method to knock together something that can hop, even if the appearance is wanting.
If that is his goal, this is the way to do it.
If you have seen the videos of that NASA guy who worked with SpaceX, and helped develop the Pica heatshield, (can't remember his name, but it was a series of short interviews), you are familiar with the culture there of being able to order stuff up from McMaster Carr, and put a test prototype together the next day to see what happens, and this seems to fit that profile.
Though they probably didn't get the metal from McMaster lol
So whether Elon is angry at how it looks, or this was the expectation, it is the fastest and cheapest way to get a Starship prototype hopping, and the appearance really doesn't matter for the testing, since it won't be going fast enough to have any effect.
And using stainless steel is just because he wants it to look shiny like the final version lol
As far as tanks, he doesn't need large or super light tanks for this first prototype. For initial testing, he can probably just use umbilicals, or small tanks.
In order to make this shape with stainless steel, you basically need to use the same method that car body panels use, and hydroform or press them, so each panel is already shaped properly for the location it needs to go.
This however requires extensive time and work making the dies for each section, since the sheets change shape and size as it goes up, so this is a big investment, and I can totally see him saying to just wrap it in tin foil to get it flying.
They very likely are currently working on building dies and such, and may replace the upper section as soon as they are done and some hydroformed panels are available.
So let's see what they are able to do to smooth out the tin, and remember that as long as it is being moved around and welded on, any straightening they do will just get messed up again, so they may be waiting until it is stacked before smoothing it.
Oh, and if they were building this for anything other than an actual test prototype, they would NOT be making the top to look like a steam punk Burning Man art installation. The very fact that it is ugly and utilitarian, for something that Elon is doing, tells me that it is for hard science quickly.
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As a hydraulics guy, I just want point out the bits that I recognize lol
On upper side of the upper blue actuator cylinder, you can see a silver rectangle, with a smaller silver rectangle one above it that has white wires coming out.
The larger one will be the 3 position spool valve (extend/hold/retract) with the pressure and return lines coming into it, and the smaller one is the wiring junction box.
It will then either have hard lines running from the valve to each end of the cylinder, or it may have bored channels inside the walls of the cylinder.
Then at the rear end of the cylinders, you can see another box with wires coming out, and that is going to be the linear positioning sensor that tells the computers exactly how far out the cylinder is extended, thus what angle the grid fin is at.
Judging by its position, I would guess that the center of the piston and rod is bored out, and a skinny tube runs down the center of the bore from the rear end of the cylinder. Inside the tube would be magnetic sensors, and there would be a magnet imbedded in the piston, allowing the exact position to be detected.
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@cowpotpi3 they go to orbit more frequently than any other company ever has, they are the reigning expert on that, so your barb falls flat.
If you are talking about the test flight of Super Heavy, it actually was in orbit, but they specifically planned the trajectory so it would not stay in orbit, but return in the desired empty part of the ocean, so that part of the flight worked perfectly.
Getting to orbit is not the hard part, getting the rocket to to make a controlled reentry is the hard part, which is why no one else has done this, and so a few test flights is not a bad thing.
And yes, it's taking longer than they hoped, but it's not as far behind as the Boeing Starliner! Lol
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@MillionFoul the Max crashes are exactly the same root cause, arrogance and ignoring engineering testing practices to save a buck and speed things up.
They had never tested the MCAS system in many different failure modes, including loss of AOA vane on takeoff with no AOA Disagree indicator.
They did the paperwork and said that runaway trim procedures would take care of any issues, and most of the people who were looking at safety and testing were not even aware of how powerful the software had become, and the people who expressed concerns were shut down.
And all the people like you who are saying that all the proper testing and certification had been done, are just saying that the process of testing and certification is broken, because it should never have let so many arrogant assumptions slip by without being verified.
For instance, they discovered that even with US pilots, the assumption that the runaway trim procedures could be done in a certain length of time, which was an assumption that they have been making for decades, turned out not to be reliable, and not just for foreign pilots.
Pilots are trained differently than they were when that standard assumption was made when most pilots had a military background, and hand flying was the only way to fly a plane.
So when you hear "we tested everything and it all met the requirements" it doesn't mean that they didn't mess up, it means that the messing up was done in assumptions and shortcuts in the testing and verification process.
And MCAS didn't get thoroughly tested, just as Starliner didn't get thoroughly tested.
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@riparianlife97701 and yet SpaceX still sets itself apart from Old Space, because it's actually logical to build them in California (LA is an aerospace engineering center, so lots of potential employees, nearby research labs, etc, plus they got a large facility cheap from McDonnell Douglas or somebody. So California was the best place to put the early design and construction, just as Fremont was the best place to start Tesla), test them in Texas (they took over an existing rocket test facility, and they don't have to worry about California pollution rules lol, and it's basically on the way to Florida. Testing them wouldn't be practical in either California or Florida), and then launching in Florida is a given because that's where the launch pads are.
With NASA, Boeing, etc, they spread out the facilities all over the place just to keep the politicians happy, and it makes no scientific sense splitting teams up and having to transport parts all over and back again.
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I am surprised that no one is talking about using the ISS as a staging facility for space missions.
It is easy to launch to, high weight capacities with low delta v needed so easy reusablility and heavier payloads.
You basically send the empty Orion capsule up on whatever rocket works best, and berth it to the ISS.
Then you send up whatever works best as a space tug to get it to the moon, and using the Canada Arm on the ISS, and a space walk if needed, you connect them.
Then you send up fuel, and using the Canada Arm you fuel it. (if you don't want to fuel at the station, you just dock the tanker to the side of the moon assembly, connect the hoses using the arm, and then after it leaves the station and is a safe distance away, you start the fueling process).
Then to get the crew on it, you send them up on Crew Dragon, and either transfer at the ISS, or if you want to do the off-station fueling and not have astronauts on board during the fueling, you dock the Dragon to the Orion after fueling is complete.
Then you jettison the tanker, send the Dragon back to the ISS as a back up reentry vehicle in case Orion has issues, and blast off towards the moon.
And while this is a lot of steps, it requires very little additional engineering, because instead of having to design special automatic in orbit docking systems, you just have to make sure that things can be bolted together by the astronauts, and add Canada Arm grapple points.
You could probably send up the extra Falcon loads and do the extra engineering for less than a years budget for the SLS.
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@A.Lifecraft put your hand through a hole it barely fits through, then spread your fingers out, grab a tennis ball, and duct tape your fingers around it, and then try to pull your hand back through the hole. It won't go lol
There are styles of wedge sockets where the tension simply pulls a wedge in tighter, often used to terminate crane cables because it's easily removable, but the poured style are the ultimate termination for a cable.
The cable wires are splayed out to evenly fill the cone of the socket, and then they are mechanically and chemically cleaned.
The metal, zinc, or a zinc based alloy is then poured in, and it's like soldering or brazing to each individual wire strand.
So there is no way for it to loosen around the wires or corrode inside the metal plug, any more than a proper solder joint will loosen around the wires. It tins the metal and forms a metallurgical bond, actually forming an alloy layer of a combination of the base metal and the solder metal. This is in addition to any mechanical or adhesion bonds.
So the zinc is held to the base metal with as much force as its held to itself, as long as the formulation is correct to be able to wet the base metal.
So now, we have a tapered plug of solid metal bonded to thousands of wires inside.
When you apply tension to it, the taper wedges it deeper into the socket, which compresses the plug of metal, squeezing down on the wires inside it.
Since the potting metal is a little bit soft, it does compress the tighter it is pulled on, creating a very tight wedging action on the cable strands.
As long as it is done properly, you can't get corrosion inside the plug, and the wires can never slip out.
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@PistonAvatarGuy where's the Booster? Lol
From scratch, they have built 2 Starship upper stage prototypes in just a few months, while also building and flying a water tower.
In Cocoa, they already have most of the rings built for Mk4, while they are finishing up mk2.
At Boca, they are going to be using a much faster build process for mk3.
By the time mk3 or mk4 are done, they will probably have the rings prepped for a Booster ready to stack.
And with no curves or flaps or lots of other things that Starship needs and booster doesn't it will basically be a straight stack of rings, 3 bulkheads, an engine mount, and miscellaneous hardware. So it should go much faster than this.
The part they have to wait on is the engines being built, and I guess we will just have to see how they end up working, but a lot of the best rocket scientists are working for Elon, so I wouldn't bet against him. He's got a pretty good track record of making things work.
Also, in Soviet Russia, they they did not have the iterative design philosophy that Elon has, so while it may not be much right now, it's just the first rough prototype, and if it fails, they will figure out why and try again. The N1 was more like an SLS project, and failure killed it politically, and they got no more money to improve it.
Starship is designed by the people who have the benefit of all previous rocket technology, so if they believe it's possible, they have better chance of succeeding the the N1 did.
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@PistonAvatarGuy as for the SLS being a completed design, why do you think they keep having delays? They are making iterative changes too, just using multi million dollar jigs that have to be scrapped, and having to rebuild custom buildings for the changes.
The built a custom rolling gantry for the test unit, and will have to build another later for the full size SLS.
It's working on the same process as SpaceX, just with massive overhead and slow bureaucracy.
And the one they are almost done building now, which then has to go through months and months of testing after transporting it to a different congressional district, is just a test prototype which will be totally destroyed in the test process.
As far as I know, they haven't even begun building the next one which will be prototype number 2, and they haven't started building the upper stages that are able to do the actual exploration missions.
So no, it's not a final design, it's still in the prototype and testing phase.
What SpaceX does differently is cut out all the pork, let the engineers build something, test it, build a better one, test it, and keep going until you get something that works right.
That's how they got Falcon 1 reaching orbit on the 4th attempt, to Falcon Heavy with landing boosters, and then a flying water tank, and now this, in 10 years.
And while you may have a bad opinion about it, their track record is pretty good at actually doing what they set out to do.
And if one gets destroyed in the process of testing, well, every SLS built is going to be destroyed, so what's the problem? Lol
And they will keep iterating until they get it right.
And if Raptor has problems that haven't shown up in testing yet, they will work on it until they solve it.
And by letting the engineers do what they know, and cutting out the bureaucracy, they can work through this process in days and months, instead of years like nasa and contractors do.
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@scottmanley as someone who long lived in typical California terrain where underground would be most useful, and also worked in construction and underground utilities in those areas, the reason they don't do it is because it would be incredibly expensive, and require cutting swaths though the land about the same as putting an oil pipeline in.
Most of the California hills are rock, and digging trenches of any size either requires a very long time with large hydraulic hammers on giant excavators, or blasting. Neither of which the neighbors would appreciate.
In much of it the rock is too hard for breaking, and so would require blasting.
And don't be picturing a 1 foot wide trench a couple of feet deep, if you are installing anything high voltage, you are going to be looking at a 3 to 4 foot wide trench, probably 8 or 10 feet deep, and all the material removed gets trucked away, and then it's backfilled with imported sand and capped with cement.
There is no way they would be given the permits to do this, with the required extensive clearing and road building that it would require, and would take decades just to work through the environmental impact studies and deal with fish protection plans etc.
If this were soft and level ground, it's only several times more expensive, but those aren't the places where the fire danger is high, which is the mountains and canyons and high places where the wind is highest, and where you are on shallow bedrock.
Many of the lines currently at risk are installed using helicopters, and since there would be no way to install a oil pipeline through the same terrain, they would have to be routed miles out of the way, increasing the costs many fold again.
When you look at the places that do underground utilities, you will find that they are mostly on dirt, and don't have much shallow bedrock to deal with, and also that they have much smaller areas, and so they aren't dealing with a 200 mile run through rugged mountains.
There are places where it makes sense, and where they are putting it underground, but the majority of places where underground would be nice, it's not a practical option, and it's not just expensive, it's unbelievably expensive, and incredibly damaging to the environment.
So I am not trying to defend pg&e, just giving my experience as someone who has done a lot of digging in those areas, and I watched a lot of pipelines being installed, and what they had to fight with.
My little town up in the hills above the Napa Valley in many places has the road asphalt directly on the rock surface, and it's common for the water line and the gas line to be in a trench scraped into the bedrock barely below the asphalt, sometimes with the asphalt directly on it. (leading to frequent leaks lol)
In order to put the power lines underground you would have to blast trenches through this everywhere....
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@Bourinos02 Starlink is not currently making a Profit, thus it's not viable as a stand alone business.
But no business is viable until after it's actually running.
But Starlink is not vapor ware for all the hundreds of thousands of people using it every day, and growing as fast as they can build dishes.
So another of your arguments is dashed on the rocks of reality.
And Elon has said it will take years to get Starlink completed and ready to start making a profit, but in the phase where they are still investing capital into the construction, no, no one expects a profit.
How long and how many billions into Uber? And have they made a profit?
The Vegas Loop will show its potential in time, it so far is working better and faster and a LOT cheaper than some of the other options proposed for the same project, so even if it's not a finished product as Elon hopes yet, it is still functional.
If you don't understand how projects can be delayed, then I guess you will never understand how the Tesla Semi has been under development for several years now, and how that doesn't mean it's vapor wear, just that it's more difficult than they expected.
And what will you say when they start delivering them in probably a few weeks and they are hauling for Pepsi/Frito Lay in Modesto, where they are currently building the MegaCharger in preparation for the delivery?
Will you just move the goal posts and find some excuse why it's still not real?
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