nwt
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Everything posted by nwt
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This has been a weird thread to catch up on. It seems to have nothing to do with either atheism or morals anymore now that the goalposts have moved so many times. It seems like there are a lot of arguments now about whether or not free will exists, but what I've lost now is: What is the overall point mbohu is currently trying to defend? Is it simply that free will exists? Is anyone refuting that? I'm always amused with people bring up Schrödinger's cat, as it seems to *always* be misinterpreted. People seem to try to use it to support superposition theory when in reality Schrödinger's entire point in the thought experiment was to show how silly it was. His point was that this theory says a cat should be both alive and dead, and that obviously isn't possible, therefore the theory is wrong. This idea that it was some serious explanation for how a cat could actually be both alive and dead is hilarious and infuriating to me.
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A heavier plane doesn't just climb slower, it consumes more energy to climb even if we assume 100% efficiency for the entire system. Not to mention there are also other inefficiencies of flight that would not be improved by a change to electric. I'm not saying this isn't ever going to work, I'm only meaning to say that I don't think the scenario you posed (batteries for x minutes plus 30 weighs the same as a full load of fuel) is the obvious inflection point I think you were implying.
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Sorry... I mean no offense, but this looks like just more hand-waving and a priori statements. How did you arrive at this 10-20% figure and why is 20% acceptable? I don't understand your point about noise floor... if my Otter is going to become 20% slower than it is now, why should I care that it's still faster than someone else's? e: You're also (I think) assuming that an Otter with a full load of both fuel and jumpers will be within MTOW. That may be true and maybe you've actually done the math, but if it is just an assumption it's not a fair one. e2: Another thing to consider is that we may need to stay under max landing weight rather than max takeoff weight. If something happens and we are unable to drop jumpers, we can't lighten the load by burning off fuel. Not a huge deal because the difference is only 200 lbs, but something to think about.
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A heavier airplane will climb slower than a lighter one, everything else being equal. This is a hard fact and you can't hand-wave it away. If you are saying a Magnix-equipped Otter at max gross will get to altitude faster than our current Otters at their current weight... perhaps that might be true but that's a claim that needs to be supported and not just stated a priori.
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That might be true, but it might not be. How much more time will it take to get to altitude with that extra weight? How many more planes will a dropzone need to acquire to compensate for this reduced lift capacity? Will jumpers tolerate the longer ride? e: Also, it becomes apparent that increased flight time will increase the required battery capacity as well.
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This is certainly impressive, but the proper comparison would be to the fuel load used for skydiving. This is a really nice synergy! Using today's dollars as was done in the chart is the proper comparison, and assuming the money available to you goes up at the same rate as inflation is the correct assumption. That's how inflation works and I'm not sure where you mean to go with this.
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I hope you're right!
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Ooh very cool--I took a couple canopy courses with Pete!
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That's really interesting!
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Most piston engine planes run just fine on unleaded gas.
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Right... I think everyone would agree that the change will take place if it becomes practical to do so. What we've been discussing is if and when that will happen. If that happens then obviously people will convert. I think that's really unlikely to happen in the timescales we've been discussing. It might not, actually. The main reason for varying prop pitch is to keep the engine in the relatively narrow RPM band where it works best. Electric motors have a much wider band, and it may cruise just fine with a fixed pitch prop for the same reason it climbs good with fixed pitch.
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So what? It's still only going to carry 4 jumpers. How much will the electric motor plus batteries weigh, and how much will it cost? These small dropzones are very capital-limited. If we weren't, we wouldn't be running piston aircraft built 65 years ago. It's not like we don't have better options available if we had more money to spend.
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My home DZ is a single C182 operation and I am all too familiar with what that can mean for reliability. But realistically these DZs will be the last to switch to electric. I'm not sure what you mean to get at here. I'm sure everyone agrees that turbines don't last forever. For the sake of this discussion, does it matter which particular component of a turbine power plant is the weak link?
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Yes, these are clear advantages for electric motors, but we were talking about safety. There's no reason not to feel perfectly safe in a twin otter. How often does a gearbox fail in flight? I saw a presentation from a small company doing electric propulsion, and he said the real killer app for this tech is VTOL aircraft for transport within a large city, where noise is the limiting factor. The flat torque curve allows for large props spinning at lower RPMs, resulting in less noise. That makes a lot of sense regardless of energy storage (batteries vs. hybrid). However, that doesn't do nearly as much for us--most of the advantage for us is in battery storage. I'm not saying there wouldn't be an advantages at all, but they would probably be relatively small and not very interesting to the jumper's POV, if they made it worth implementing at all.
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Compared to pistons for sure. Turbines seem pretty reliable, though.
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Everyone already understands that an electric plane could be much cheaper to run. Harping on that does nothing to support the feasibility. What is the evidence that we will hit the required energy storage densities on your timeline? You're advocating for DZOs to start planning now. What do you mean by that? What would you have them do, specifically?
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The exact number isn't so important, so long as we can agree that electing Biden will save lives.
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So you agree, then?
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Probably a lot.
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You state this as if it's obvious and uncontroversial but I don't think I agree and I doubt he does either.
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The thing about cantaloupes is a lame question, but I don't see the connection.
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Right. I am advocating for routine, asymptomatic testing. I feel I made this pretty clear. This sort of incorrect thinking seems to be pretty common and it's been very frustrating for me. For this and other measures, it just isn't true that it won't be helpful with less than 100% compliance. There's not even any logical reason to think that. Certainly the more people who participate, the more effective the measure will be, and partial participation will be partially effective. Why do you think that? Because of what you think you saw last time you went outside? You think the number of people you think you saw without a mask on your block today is representative of the entire country or world? Really?
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This is what he said: Seems like he's saying cheap, accurate, fast testing is what we need, and he's right. It's not only about helping the person infected, it's also about reducing the spread from that person. If an asymptomatic person finds out early that he has it, that person can isolate and infect fewer people on average. That should have a great positive impact to the course of this pandemic, which is to a large degree driven by asymptomatic spread.
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The University of Illinois is doing great work on testing. Most undergrad students are required to test 2x weekly, or 3x for those identified as high risk. 1x/week for grad students and staff. Anyone can test more than that if they want at no direct cost to themselves and results have been same-day. A typical day is around 10,000 tests.
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Yes, I think regen would just be a bit of icing. It might end up being useful, but I don't think the success of electric aircraft will depend on it.
