This is very far from realty as based to our current time… hydrogen is expensive and if in-case you have the fund for it, still you need to have expensive way of transporting the element to the factory.
I am not discouraging you but… Machine shop and persons behind are not just the topic here… FUNDS FUNDS FUNDS… yes you read it right. This project needs a great mining of FUNDS.
Programming in this project is so serious that you need an ocean of coffee for this and good thing it code be done remotely.
But testing of devices and parts are more serious man. If you managed to develop an RC plane with denatured gas on it, well there’s a lot of trial and error and it could cost you big though.
I feel your great desire of solution. but you need a great momentum of elements (People involve, Funds, Dedication, Resources, Ability, etc).
Draft a clear plan on a black-and-white explanation and many would want to be part of this project even me.