The Conventional Hydroplane
After careful evaluation of 1950 racing. I still feel that the conventional hydro has greater possibilities as a practical competitive boat than do airborne craft of the Slo-Mo-Shun type. The conventional must be a safer boat; it definitely has better turning qualities for the reason that it will bank. It is much better in rough going and has a more practical value. Boats of this design have been built—and performed successfully—in sizes up to 65 feet. I myself designed and built a 40-footer of this type for power with a Liberty engine. She was quite fast and during prohibition clays she carried honor across Like Erie through all kinds of weather—successfully, according to all accounts. This could hardly be accomplished with an airborne type. For these reasons I must string along with the conventional, or stepped. hydroplane. Should I continue designing race boats, they will certainly be along conventional lines.
The Slo-Mo-Shun is without question a remarkable boat, and the boys from Seattle deserve due credit for its development. The record of 160 m.p.h. could stand for quite some time. In fact, it is my opinion that this record could not be duplicated by the same boat in another trial. Remember Miss America X? As we know, this boat made a record just under 125 m.p.h. A year or so later, with 1600 added horsepower, her top speed was around 119 m.p.h. This has happened many a time and it just seems that conditions are partly responsible for speed records.
On the other hand, when we consider the remarkable performance of Paul Sawyer's Alter Ego, an.airborne 225 hydro, it would indicate that even 160 miles is not a safe record. If Alter Ego were used as a one-half size model, the corresponding speed of the scaled-up version would be much greater than that of Slo-Mo-Shun.
Beginning with the Hurricane—the forerunner of this type—the airborne boats have developed many troubles. In
critical and not so consistent as the conventionals. They are also suited more to quiet waters, and therefore could not possibly have any great practical value, in my opinion.
Even though the airborne boats were developed from three-point suspension designs, I do not consider that they can be rated as three pointers. At speed they run on only two points of the hull (the propeller cannot be considered part of the hull) and are, as I understand from the designer. approximately 85 to 90 per cent airborne.
I would like to illustrate my preference for the conventional hydro by referring to two recent unlimited boats of my design, both falling into the conventional category, My Sweetie, designed and built in 1948, weighed 2480 lbs, complete except for the power plant. Her engine scaled 1465 lbs. She made a fair showing the first year and except for an unsecured battery pounding through the bottom, Sweetie could well have won the Gold Cup. In 1949, reenforcement of the hull addled 720 lbs., yet she did very well, winning most of her races and turning three qualifying laps at 92.4 m.p.h. She lost the Harmsworth through circumstances unrelated to hull design. In the first heat My Sweetie got off to a bad start—20 seconds behind the gun—yet overtook all the other boats and came out of the lower turn first. Some of the boats she overhauled later made laps at better than 98 m.p.h. Allowing for the lost 20 seconds, she ran this lap close to 102 m.p.h. While leading by almost one-half mile, Sweetie suffered damage to her water intake and was forced out. A new hull of the Sweetie design could be miles faster.
Miss Pepsi, a 1950 product, weighed close to 9,300 lbs. She was timed as high as 114 m.p.h. over the Harmsworth course. I was present when three competent timers varied only a few fifths of a second in catching her at 111. This showing for an undeveloped boat would indicate that she could be a dangerous contender in 1951. R.p.ms on these runs varied between 3000 and :3100. The engines had run up to better than 3200 on acceptance trials for the power plant, with promise of reaching 3400. Miss Pepsi was a good all-round competition boat. She turned like a runabout and was good in rough water. Another 10 miles could easily be obtained from a new, improved Pepsi.
Consider, if you will, the little model hydroplanes powered with the same sort of engines used in model airplanes. The present record of a single step model is 70.2. Were we to use these little boats as one-twelfth size models, the corresponding speed of the full-size boat would be better than 240 m.p.h. This will indicate the possibilities of conventional hydros; we still have lots to shoot at.
Now, as Al Smith would have said, let's look at the record. The Gold Cup of 1950 was of course won by Slo-Mo-Shun. But Sweetie could well have won this one if Bill Cantrell, instead of driving under the handicap of painful injuries suffered several days previously, had turned Sweetie over to Lou Fageol at the start of the race. As we saw, when Fageol took over he led Slo-Mo-Shun in every lap by six or more seconds and was in the lead by almost 13 miles when the engine ran out of oil putting Sweetie out of the race. Sweetie's 86.2 mile lap was the fastest of the race.
The Harmsworth was won by Slo-Mo-Shun handily, against little opposition. Had the Pepsi been selected for the American team, it could have resulted in quite a race. She had shown a lot of speed and might have gotten through. She was being developed gradually at the time.
In the Silver Cup, Slo-Mo-Shun got off to a good start, leading by some one-quarter mile. However, Miss Pepsi passed her before she got to the first turn. Chuck Thompson, driving Pepsi, gave Slo-Mo a wide berth on the turn, then was catching up to her on the backstretch when his goggles became coated with oil spray and it became necessary to slow down. The oil leak was reduced to some extent after each succeeding heat and in the fourth Thompson set a lap record of 107.654 and a heat mark of 107.394. His r.p.ms were between 3000 and 3100. Slo-Mo-Shun did not come out after the first heat. Water conditions were made to order for the airborne type and the rougher water we usually have, I'm sure, would favor My Sweetie and Miss Pepsi.
Records at the Washington, D.C., races were made by Pepsi and should stand for some time, especially since water conditions in Washington never seem to be favorable. Her 2½-mile lap speed was 95.38, heat-88.725, and race-83.45.
The above facts are, I believe, convincing proof of the qualities and values of the conventional stepped hydroplane. This design has come through most of the races more consistently, having far less trouble than the airborne which must be limited by water conditions. I have seen nothing in the past season's performance of airborne boats which I could accept without reservation. There is still a question mark which can be settled only in the races in August.
In my opinion, much faster boats than any of the present ones can be built in the conventional type. Pepsi, when fully developed, will be a very fast, good-performing boat. This design must not be considered passé, but rather still in the running—very much in the running.
(Reprinted from Yachting, April 1951)
History Home Page
This page was last revised Thursday, April 01, 2010 .
Your comments and suggestions are appreciated. Email us at firstname.lastname@example.org
© Leslie Field, 2006