Flash steam tethered hydroplane

This is my flash steam hydro that im building.

Shes an A class boat, with a maximum permitted weight of 16 pounds and no other limitations. The hull uses 2 of those pounds, the engine another 3, the prop and driveshaft another 1, and pumps etc about another pound. So i have about 9 pounds of weight to play with, which should hopefully equate to about 25 feet of 1/4 inch stainless tube, and a triple jet venturi boiler to provide the heat, and some ceramic insulation to contain it. The current record for these boats is over 130 Mph. From a steam boat. Hehehehehehh.....

Shes going to be sprayed blue, natch....