Some follow up thoughts on the post "Automatic Refueling..." where we looked into a possible path for extending the range of electric aircraft.
Battery energy density. While there is no disputing that electric airplanes will need incredibly high energy densities to allow for sufficient range to be super appealing to consumers (even with range extending support craft). One thing to keep in mind is that the calculations for energy density are based on the assumption that the batteries are only storing power and doing nothing for the structure of the vehcicle. If researchers are able to develop a storage mechanism that can improve structural integrity, that would be just fantastic. While structural batteries would be really cool I don't want to be so naive as to assume that a structural battery would have the same energy density as those that purely store energy. As they could not readily be removed from the body of the airplane structural batteries would need to have incredibly long life expectancies, most lithium ion batteries will lose something along the lines of 20+% of their energy density after a few thousand full charge discharge cycles. The Physics World article "Structural supercapacitors take a load on" shows that developments are already underway.
Assistive Take Off and Landing. While midflight recharging is cool, to ensure maximum range for your electric plane it may be a good idea to have assisted take off and landing, similar to what was described in "Giving Planes an Electric Boost".
Modes of recharging mid flight: In "Automatic Refueling..." we talked about the need for relatively rapid rates of energy transfer between the primary electric airplane and the support vehicle. If only one support vehicle at a time is able to transfer power there is a concern as to how quickly it can move that power from one unit to another. As of now it is hard to say how support vehicles and the primary electric plane will dock with eachother and how frequently, in principal there should be no difference with having one support vehicle or many docking at various times to move energy. In practice it would most likely be more complicated, if a physical connection is used to transfer power, each docking vehicle will require some degree of additional complexity and wiring. On the other hand if energy is transferred wirelessly there are concerns about interference in navigation tools and the weight of the reciever, as well as transmission range (basically this is a really hard engineering problem)
Mid-Flight Passenger Transfer In the future scenario, it was suggested that support aircraft might be designed to carry a small number of passengers. One big concern for this idea to work is ensuring the safe transfer of passengers mid flight. For passengers to be able to get into a small transfer vehicle and safely reach their destination there would need to be a way of ensuring that consumers could avoid the disruption of turbulence without them being excessivley jostled by the air all without flying to far from their destination. One option might be to simply have a clause on every ticket saying that for destinations that are not being visited by the primary electric vehicle, they will only guarntee that they will get you to the closest support vehicl landing pad that they can safely move you to.
Those are my thoughts as of now, if you have any questions or insights of your own please feel free to add them
I will add on that I have been trying to get details about the ranges and capabilities of hydrogen fuel cell airplanes, at this time I can't get solid enough info to say much. From my perspective I will say I'm more ok with electric aircraft using fuelcell tech than cars, my reasoning is that for electric cars our biggest concern is per person affordability and for ground based vehicles current battery tech is on a good enough trajectory. The economics of the airline industry are a closer match to the particular characteristics of hydrogen fuelcell tech (as I understand things).
Battery energy density. While there is no disputing that electric airplanes will need incredibly high energy densities to allow for sufficient range to be super appealing to consumers (even with range extending support craft). One thing to keep in mind is that the calculations for energy density are based on the assumption that the batteries are only storing power and doing nothing for the structure of the vehcicle. If researchers are able to develop a storage mechanism that can improve structural integrity, that would be just fantastic. While structural batteries would be really cool I don't want to be so naive as to assume that a structural battery would have the same energy density as those that purely store energy. As they could not readily be removed from the body of the airplane structural batteries would need to have incredibly long life expectancies, most lithium ion batteries will lose something along the lines of 20+% of their energy density after a few thousand full charge discharge cycles. The Physics World article "Structural supercapacitors take a load on" shows that developments are already underway.
Assistive Take Off and Landing. While midflight recharging is cool, to ensure maximum range for your electric plane it may be a good idea to have assisted take off and landing, similar to what was described in "Giving Planes an Electric Boost".
Modes of recharging mid flight: In "Automatic Refueling..." we talked about the need for relatively rapid rates of energy transfer between the primary electric airplane and the support vehicle. If only one support vehicle at a time is able to transfer power there is a concern as to how quickly it can move that power from one unit to another. As of now it is hard to say how support vehicles and the primary electric plane will dock with eachother and how frequently, in principal there should be no difference with having one support vehicle or many docking at various times to move energy. In practice it would most likely be more complicated, if a physical connection is used to transfer power, each docking vehicle will require some degree of additional complexity and wiring. On the other hand if energy is transferred wirelessly there are concerns about interference in navigation tools and the weight of the reciever, as well as transmission range (basically this is a really hard engineering problem)
Mid-Flight Passenger Transfer In the future scenario, it was suggested that support aircraft might be designed to carry a small number of passengers. One big concern for this idea to work is ensuring the safe transfer of passengers mid flight. For passengers to be able to get into a small transfer vehicle and safely reach their destination there would need to be a way of ensuring that consumers could avoid the disruption of turbulence without them being excessivley jostled by the air all without flying to far from their destination. One option might be to simply have a clause on every ticket saying that for destinations that are not being visited by the primary electric vehicle, they will only guarntee that they will get you to the closest support vehicl landing pad that they can safely move you to.
Those are my thoughts as of now, if you have any questions or insights of your own please feel free to add them
I will add on that I have been trying to get details about the ranges and capabilities of hydrogen fuel cell airplanes, at this time I can't get solid enough info to say much. From my perspective I will say I'm more ok with electric aircraft using fuelcell tech than cars, my reasoning is that for electric cars our biggest concern is per person affordability and for ground based vehicles current battery tech is on a good enough trajectory. The economics of the airline industry are a closer match to the particular characteristics of hydrogen fuelcell tech (as I understand things).
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