RE: Project... maybe...
hmm... seems that you are right.
although they are good at moving large quantities of water, they aren't very good at moving it quickly, nor are they good at holding the backpressure generated by a smaller nozzle...
I may try to build a jet pump from scratch, resembling the Graupner, but chances are that it will probably be even less powerful...
That leaves me with two choices, prop driven in air or water, and I will try both (water first because that would be kinda unusual[8D])
Its a bit sad that this project is being derailed ALREADY, but hey, I guess that it's better to have that happen now then when I am nearing completion.
Thank you for the doubt expressed, as it helped me realize I need to think this over... now to plan B