Manuscripts/Mixed Material Bulletins, from July 13, 1908 to September 28, 1908
apparatus up to speeds of over 40 miles an hour. Beyond this the air resistance becomes a limiting factor.
These results are very encouraging when we consider the simplicity of the arrangements, the relatively low power and the tremendous lift exerted by the hydroplanes.
M. Forlanini uses a 75 horse-power engine geared to two large aerial propellers one in the bow and one in the stern turning in opposite directions. The propellers each have five blades 1.7 meters diameter, and a pitch of 6 meters. The hydroplanes are on a kind of a rack extending from either side of the boat and arranged in superposed fashion like a Venetian Blind, so that as the boat lifts out of the water the submerged hydroplane area is proportionally reduced. The planes are very narrow from fore to aft and he states that at a speed of 70 kilometers an hour the entire weight of the boat (1650 kg) was supported upon a surface of only .125 square meters. This gives the astonishing result that one square meter is sufficient to support 11 metric tons at this speed. (11000 kgs).
Now judging from these figures I think we should be able to get some good results with the little catamaran on which we have been trying out some hydroplanes.
The Edbert carrying a man and with the four cylinder 20 horse-power motor, and the 1.5 meter propeller weighs about 500 lbs. The thrust can safely be counted on as 90 lbs., and this according to M. Forlanini is more than twice what we need to obtain high speed.
(Signed) F.W. Baldwin.