Originally Posted by
RatherBeFlying
So now we need an airtight, light weight flexible solar panel skin.
Well,
that might be much more realistically possible than many things about this project. You could pretty certainly get flexible panels that would conform to the upper surfaces. It also occurs to me that you could basically plan to run the ICEs at optimum efficiency, and if this generated more power than was needed for propulsion, take some of the power to charge batteries for the electrics. As an experiment in hybrid power, you can see the attractions.