[lukeschlather]

> The first paragraph is incorrect. The wing has to be built to withstand lift, which far exceeds the weight of the engines. The weight force of the engine typically counteracts the lifting force, which means -- if you're clever with your design -- you can build a lighter wing structure with a bigger engine.

But couldn't you achieve the same effect by locating batteries in the wing? The point of the previous comment is that comparing fuel weight with battery weight is deceptive because electric engines are lighter. That doesn't mean an electric engine system is lighter weight than a conventional jet engine system. (So the structural design you're describing sounds feasible.)

[aerodude]

Yeah you could; you would probably place the batteries in the wing where fuel is located, which potentially has benefits.

I was pointing out that the reasoning was flawed. The engine is not the limiting factor in the design of the wing, and in fact can let you reduce the mass of the wing. An electric motor and airframe might be lighter than an engine and airframe depending on the design. However, you do need to compare the battery weight with the fuel weight, because the energy has to come from somewhere, and an airframe is designed with that reduction in weight in mind. It's hard to stress just how important energy density is for an aircraft.