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About AngrybobH

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    Sr. Spacecraft Engineer

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  1. United Airlines flight 232 managed a quite amazing landing (mostly crash) with a failure mode that was considered unflyable(all 3 hydraulic systems failed). I really doubt that starship would have a capability to pull something out like that with a similar level of failure. Of course, I would still get on a starship if it were man rated.
  2. KSPI-E has some forms of xenon capture/production. It is a huge mod though. I personally like it but it can be a bit much for some people. Xenon is produced in reactors or can be harvested from atmospheres that have it. Bonus is you can power the ions with the reactor that produces xenon, though you will need another source too.
  3. The timing of a winter storm that is supposed to bring ice to Texas is in perfect alignment with this transit. Texas...sigh...Hopefully someone takes a picture.
  4. It is but I think it isn't fully optimized yet. They want the thing out there and 'proven' reliable (by de-tuning it slightly). Car companies can suffer greatly when public opinion sours on a product. Look at the pinto you mentioned. If it wasn't for the penny pinchers it would have had a bladder fuel tank, air bags, and most of a roll cage. With those left out and the vehicle not redesigned made it known as one of the worst cars ever. The Pontiac Fiero was another example(and appropriately named). First year of those caught on fire. They fixed it by the half year but, its' reputation never recovered. 3 years later they cancelled it. Funny thing is, if you take the skinny wheels off a prius and put them on a same year corolla, you get the same mileage on the highway and very close in the city. Same is true for the civic and civic hybrid. turns out the batteries and inverter are VERY heavy and skinny tires, while bad for handling, reduce rolling resistance really well. Absolutely electric cars can do insane things but you cut into range very quickly if you use it. The same is true for ICE motors too. For example I have a Mercury Comet resto-mod (modern tech on an old car) that has a 413 bhp v8. It knocks down 24-26 mpg(better than most modern high HP v6s) on the highway cruising at sane speeds. On the track it gets less than 6 mpg. A very fast electric can use an entire charge in less than 10 minutes. But, when I run out of fuel, it takes 2 minutes to fill 16 gallons(~400 mile range) while an electric would require many hours to charge from empty without reducing its capacity(Yes, fast charge hurts your batteries). Hondas' design seems to be compromising on range, mpg, and power. More electric power and/or means heavier equipment so, make the engine help the motor from time to time. Making a single torque peak ICE with a generator that specializes in a single RPM and load does not sound hard. And, if I had the cash to invest, I would take a Nissan Leaf and put a system in it. But, extending the range on the highway with an ICE is just another way of masking the horrendous problems with battery technology. Piezos are cool, for sure but, for a valve, making a stack tall enough to move a sufficient distance is hard. Piezos shine when you need a valve in high pressure/low volume situation like modern diesels with their 29,900 psi fuel systems. The LNG systems are very interesting but in consumer use you tend to see the ring seal and the cylinder walls wear down much faster(LNG dilutes the engine oil). Cooler would seem to be better but really we keep the engine temp that high for emission reasons.
  5. And it had some issues like compression ignition happening before laser ignition. Quite a problem if you are not set up for for it. The regular 2.5L altima already achieves 39mpg without turbo or variable compression. Although, strangely, the 2.0 turbo VC is listed as 38mpg. It does really get out of its own way though. Also, I feel obligated to mention I work for Nissan. I really doubt this. electric motors are okay but generating power and storing it isn't really there mainly because of batteries. Charge efficiency, self discharging, energy and power density, electrodes degrading, and heat issues are all major problems of batteries on top of the fact that they are heavy. Add to that the environmental impact of mining and refining the needed materials, recharge time, and other customer bothering issues like the cost of replacing the batteries every 2-3 years and you have a significant problem to overcome. Most electric and hybrid cars are on the road to attempt to push the technology forward while getting paid by customers that believe they are/will be better. I'm not saying they won't get better but a new way to store energy is really needed. Hybridizing with a small ICE running at a constant RPM (like a train) would probably mask a bit of the issues but still not solve them. I see the energy future being in using better/cleaner infrastructure creating storable chemical fuel (like butanol) that wouldn't drastically change the way we use energy for transportation or transport the fuel. That is until a real solution to batteries multiple problems comes along. I am The problem is with the scale required for larger things like cars. And batteries don't scale real well unless you like fires in your mode of transportation. I imagine it could but methanol is also used as fuel for race engines and I also imagine you get more energy using the heat(burning it) than you would from the fuel cell with current technology. Perhaps fuel cells should be on the list as well as they could use some real work.
  6. He says " It just needs crazy up force! ". I'm sure it does. But, it makes me wonder about how loud this thing is going to be especially after it pushes away from the sound suppression system. Is the sound pressure going to break things? SpaceX surely has thought about this, right? Anyway I can't wait to see the static fire and then the eventual take off of all those raptors on SH.
  7. Look up a rotary valve from Coates, LTD. One of their valves could be easily actuated by an electric motor. Poppets are terrible for many reasons (air flow shrouding, piston interference, etc). The rotary valve has many improvements(less detonation from more quench area making higher compression is just the beginning) for recip piston engines. Combining direct injection, turbo, electric rotary valve variable actuation, and variable compression (like in the '20 Nissan 2.0 turbo) would be a huge jump in efficiency and power. I think the rotary valve is actually the new thing needed but car companies have refused buying the design and favoring in house or out of patent designs.
  8. Batteries. Our current technology is miserable and new science/engineering makes them only marginally better. I'd imagine something new would need developed to move energy storage forward but, I cannot even imagine what that would be. If I could, I'd be a billionaire overnight.
  9. how much of vision has nothing to do with the eyes but with the ability to process and retain visual information? What we see clearly isn't that large but our brains fill the rest of our 'vision' in with 'close enough' approximations from visual memory. And we miss a lot of things. Police even say eye witness testimony is often inconsistent with reality. Exactly
  10. This is something I always wished would work but, sadly, it does not. The forces experienced upon instantaneously hitting the atmosphere would shred anything we could build. Think about it this way, would you rather slow down in a car from 100 to 0 in 200 meters or 200 millimeters? The energy is the same but the time it happens in is vastly different. Another thought for you. Why do rockets worry about max Q? What speed would you be going at the exit? at what altitude/air density? what is the drag coefficient of the ship? Answer those questions and you will see that you would kill all the crew with Gs and tear the ship apart on exit unless it was made from unobtanium with an unrealistic profile. But the crew would be dead and all the cargo squished so, what would be the point? Lowering the exit speed would easily make the whole system irrelevant. And sure, more mass slows down less in atmo but then you have more mass. So more engines and fuel for circularization, more thrusters for attitude control, more fuel needed for a given DV, harder to slow it down when needed...this makes the whole ship worse for everything else. I'm not even sure the math would allow you to get the mass and drag into the correct ratio for this to even happen. Now if you ditched the vacuum chamber and then built a mag rail system higher than anything humans have ever built and it was capable of accelerating something to a typical first stage speed then you could eliminate the first stage. But, that definitely has both feet firmly planted in scifi territory. And it would have a fixed angle so, only one inclination would be possible. Great for orbital construction but not so for every other mission.
  11. What's the delay here? The capsule is built, right? Or mostly anyway. Slap that thing on a rocket and press the spacebar launch button. I thought that was the spaceX way of doing things. Why are they so different on this one thing? I understand NASA requires hoops to be jumped through but they could do their own testing as well.
  12. My guess, because I'm not 100% on it, is that it will burn the fuel faster. For reference(with a subject I am an expert on), when you add nitrous(40% oxygen vs 20% oxygen air) to a car engine if you do not add more fuel you run your engine lean and melt the combustion chambers and/or pistons because hot oxygen will react with the metal in the engine for fuel. Oxygen is not explosive nor a fuel. As it says on the bottle, it vigorously accelerates combustion. It is reactive. Not sure what a creeper is but hand grenades and dynamite have their own oxidizing agent, outside air composition does not matter. But, if there is another fuel source to be scattered and atomized and there is a bunch of O2 present,......well I'll just say fuel air bomb. Not sure about #1 in this but I'd assume that the fires would be similar. The way the heat convects because of increased density in room B could maybe be different, not sure how that would affect it though or that it would be different at all. On #2 with the setup of #3 I really don't know. the increase of density in room B could amplify the damage done but the amount of energy released would be the same in both rooms. So, I have no real guess here.
  13. I haven't seen that but I landed a spaceplane engines down on Ike then used RCS to put it on its' wheels. the wheels (large landing gear in back, medium pair in front) sank into the ground and had no touching the ground animation. It slid down the hill with no way to control steering, friction , or braking. The rest of the plane seemed to contact the ground just fine like I landed it without the wheels down. Seems like it's probably related.
  14. Can confirm that it is not a Big S only problem. Right side of my SSTO (160 parts, ~300t wet) overheats quite readily. I'm using multiple wing connectors to make the wings. This plane flew ok (not great but ok) before 1.8, now it is impossible to land. The drag seems asymmetric (haven't heard anyone complain about that). I tried the retro entry. It's strangely stable and does not overheat or start tumbling unless I go outside retrograde facing by ~1.5 degrees. Maybe I should put the engines at the nose and fly it that way.
  15. I cannot see much of a reason for large crews even in a scifi sense unless the cargo is people. But, those would not be crew, they would be passengers. It depends heavily on the intended mission of a ship as what is optimal. I think any mission would at least need command, navigation, piloting, engineering, and science crew. Maybe payload specialists? what about janitors(the toilet doesn't clean itself, or maybe it does)? And then a 2nd or 3rd shift(depending on how long a shift is and if you give them days off). In a scifi sense it looks more like an old time sail boat than todays spaceships. I think that is the idea with a lot of scifi. The manned spacecraft of today are more like a racing yacht, super expensive and not out at 'sea' long enough to need much more than the bare essentials.