Comments by "Scott Franco" (@scottfranco1962) on "eVTOL - Wall Street's Dumbest Idea Yet" video.

  1. The technology is tied to the state of battery technology. The reason that EVs are impractical for aircraft use is the weight of the batteries. Not only do they weight much more than the fuel they replace, but, unlike liquid fuel, they don't get lighter as they fly due to consumption of the fuel. If/when batteries improve significantly, that calculus will change. The other factors are: 1. Noise. Most of the noise in an aircraft is the blade noise. This is why (for example) yard leaf blowers aren't really much quieter than gas powered ones. 2. Reliability. Sorry, they comments here are just wrong. The reliability of electric motors is far greater than piston engines, and compares more directly to turbine engines. 3. Power. The horsepower output of an electric engine is significantly greater than a piston engine, and exceeds even a turbine engine per weight. This allows an electric aircraft to use multiple engines and thus gain even better reliability. Again, it mainly depends on battery technology advances. Most of the stock bets on Evtols have been about the idea that batteries will significantly improve in a short time. They actually have. They have about doubled in the last two decades, but then the battery chemistry has changed radically, from lead-acid to lithium. It is not certain we will see that much improvement in the next two decades. Also, the majority of research being done now is to reduce the cost of batteries, not so much to reduce the weight, which is not as important for ground vehicle use.
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