Comments by "kazedcat" (@kazedcat) on "Real Engineering" channel.

Stop calling soldiers horses they do not deserve the disrespect.
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@alilalani9531 You can do it in UV and no one will see it. That is why no one tried to burn down the sun for causing cancer.
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@DuyLeNguyen Blended wing will just need to limit roll rate for passenger comfort. Acceleration is distance/time². From this equation time is a more significant factor. So doubling the passengers distance from the center means the plane needs to slow the roll rate by 30% to achieve similar acceleration and slowing down roll rate by half means the passenger can be 4 times farther from the center. Now the angle of the bank in a turn is affected by the lift so you also don't expect the blended wing to have similar bank angle than conventional design. Since blended wing have larger wing surface their bank turn have higher authority and needs shallower bank angle to get similar turning radius to conventional aircraft. Again everything rely on the flight control algorithms to ensure passenger comfort.
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@DuyLeNguyen The only thing that matters for the sickness feeling is the acceleration of your body independent of the mass of the vehicle. As long as the vehicles stability control is strong enough to prevent the passenger's bodies from accelerating beyond some sickness threshold then the passengers will not feel sick. Blended wing planes already need strong stability control because it needs active stability they just need to factor in passenger comfort in their active stability algorithm. The bottom line is that if the plane is stable you will not feel sick no matter how the stability was achieve.
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Theorithical limit in charging and discharging of the capacitor. It is not 100% but very close to it. Then there are loses from extracting energy from the plasma. Overall I would guess they can recover 80% of the heat energy in the plasma. The majority of the losses should be the heat loss in their magnetic coil. I don't know how efficient superconducting coils could be. Also He3 breeder reactor would likely not break even.
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I don't get it why soend $3 on a system that is yet to be proven to work when you can spend $1 on an already proven system that is already working. If getting out of fossil fuel is crucial then why spend money on a longshot research that might give you result in 5years when you can spend that same money now on eenewables that cam be bult amd running within 6months.
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@glockmat The bomber was design to have low radar signature. I would assume this limits the shape of the plane away from the optimum MTOW.
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@Erik_123 The airbus flying V concept was designed to fit on current airport with out the need of upgrades.
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The cost analysis made wonder. How much do the electrode material of LFP batteries cost. They don't use expensive metals like cobalt and nickel. So they must be competitive with this liquid metal batteries. Their production is compatible with nickel base Li-ion batteries so they have production cost advantage. I bet LFP batteries is going to win in cost and will be the future of energy storage.
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They just need additional stairs. Blended wing planes have smaller box for the number of passenger they carry. The airport also need a new procedure so that the utility support equipment is positioned towards the back instead of the right side of the plane but all this equipment are already mobile they just need to train the crew on where to go.
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@HyperManSP Machine use as breeder reactor should have ablative lining integrated into the design. If you relax the requirement for magnetic confinement because you have no intention of extracting energy directly from the plasma then you can design a more modular reactor with swappable ablative lining. A monthly maintenance that would take 1 week to swap ablative is practical for He3 breeding. It is okay for breeder reactor to have intensive downtime.
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 @benzzoy What efficiency? Combustion efficiency is not the same as Propulsion efficiency.
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 @mintoc8853 unless you are a rocket engineer and the new engine is giving you 5% more combustion efficiency when what your rocket design need is 5% more propulsion efficiency.
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@slyseal2091 This is wrong and the video is wrong. Higher combustion efficiency gives you better thrust but it does not mean you need less propellants. To reduce propellants what is needed is higher propulsion efficiency. A significant portion of the fuel in a rocket is not burned and they are mainly use as propellant with their chemical energy untapped. RDE burns fuel more efficiently but it does not throw propellant with higher efficiency.
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@anullhandle The rocket use propulsion efficiency (ISP) not combustion efficiency so this engine does not actually apply. RDE burns better but it has no say on the tyranny of the rocket equation.
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@mintoc8853 No it does not work like that combustion does not increase mass. Even if the new engine provides 5% more energy when you calculate the added impulse you only get a square root of that 5%. So it is very misleading to calculate the 5% additional combustion efficiency as linearly equivalent to a 5% reduction in propellants.
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@mintoc8853 Yes the square root is related to kinetic energy. But we are assuming all the energy gets converted to kinetic energy. Some of them is wasted into sound energy and infrared energy which does not increase the propellants exit velocity which is what ISP is it is the propellants exit velocity. Detonation means boom supersonic boom. RDE could mean just a louder engine. I have not seen anyone calculating the actual ISP improvement of RDE.
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@mintoc8853 NASA sometimes study impossible technology hoping to get lucky. I believe there is an ISP gain with the new engine but the fact that they are hiding it makes me believe that the ISP gain is very small.
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@mintoc8853 My guess is it will become the new holy grail engine that is very fun to talk about but no one actually uses. The previous holy grail engine was the full flow stage combustion engine which have very high combustion efficiency but also very complicated. But SpaceX is bringing that engine into production so we need a new holy grail engine to inspire new engineer.
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@slyseal2091 The tyranny of the rocket equation could not be easily defeated. The easiest solution is to just build a bigger rocket. Rocketlabs for example is now building a bigger rocket using a very simple engine architecture. Better engine is the sexy solution but better propellant tanks are more practical.
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You are confusing combustion efficiency with propulsion efficiency (ISP). They are not the same thing. Higher combustion efficiency does not mean higher ISP. Higher ISP is what is necessary to reduce the needed propellants for a fix ΔV.
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@MrKentaroMotoPI Actually no. If everyone goes for highest combustion efficiency then everyone would be using full flow close combustion engine. But real rockets often use less efficient open combustion that is like 30% less efficient. Even the Saturn V uses open combustion. Only SpaceX actually uses the most combustion efficient engine architecture that is not RDE. So a better engine than what SpaceX is using is not actually very practical outside of research.
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@MrKentaroMotoPI Full flow stage combustion has higher ISP. It is you that needs to read the text books.
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@MrKentaroMotoPI Tell me how to design an open cycle engine that could match the ISP of close cycle engine. Give me an example of open cycle engine with similar ISP to a close cycle engine.
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@MrKentaroMotoPI Let me school you on rocket engine 101. ISP is driven by chamber pressure. The higher the chamber pressure the higher the ISP. In order the reach high chamber pressure you need the intake to be at a much higher pressure than the combustion chamber to allow propellant to flow in. To do this you need a compressor. To power the compressor you need a preburner or a gas generator. This where lies the problem the power that can be delivered into the compressor is dictated by the mass flow and pressure drop on the preburner. You don't want high pressure drop because that will just eat up the high pressure generated by the compressor. So the solution to reaching the highest chamber pressure is to use two preburner and use the combine mass flow of the oxidizer and the fuel to generate the power needed to drive the compressor. This is why Full Flow Stage Combustion provides the highest ISP of all stage combustion engine because it is the only cycle using all propellant mass to drive the compressor. Now class is over go read your text book because your rocketry knowledge shows to be deeply flawed.
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You can calculate the weight of empty truck by the difference in 0-60 figures between fully loaded 20seconds and empty 5seconds. Assuming constant torque and this is an over estimate because motor torque drop at higher rpm. But 60mph is low rpm so assuming constant torque is close estimate. With this empty tesla truck weighs 20,000 pounds.
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weather radar and gps are using the same frequency range. Although 5G have significant guards to protect other nearby frequency bands. old equipment might not be precise enough to filter nearby frequency band and be saturated with 5g noise. I don't agree that we should stop new technology to protect old technology. The proper solution is to upgrade equipment that have better precision in their frequency filter. Frequency spectrum is limited resource so we should not let old technology to waste those valuable resources.
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Tandem reactor might reduce the number of capacitor but you will still need lots of power electronics to control everything and most of the losses will be on the power electronics. It is also possible to store energy on the rotating plasma vortex.
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How many digit's of pi did LIGO and EHT used for their calculation?
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This is not much of a problem with electric planes because you have large amount of excess power as long as you have available energy. If designed properly you can recover energy during landing with regenerative propellers to give you enough power to land.
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