World Speed Record Attempt 
Sayres Sets World Record of 160 mph 
Slo-Mo-Shun IV, a Northwest boat, broke all existing records for unlimited hydroplanes
on Lake Washington June 26
Motion pictures of a low hydroplane with sweeping lines prop-riding effortlessly across Lake Washington was the first proof to the outside world that the fastest boat of all time had been designed by Ted Jones and built by Anchor Jensen for Stanley S. Sayres, all of Seattle. Locally, the boat produced by this team of men, Slo-Mo-Shun IV, was a secret too spectacular to keep well, but her `performance was almost too fantastic to convince men on distant waterfronts.
When Kent Hitchcock of Newport Harbor, California, technical advisor to the president of the American Power Boat Association, viewed the movies of the Slo-Mo-Shun IV in action, he was so impressed that he immediately offered to set up a time trial to establish officially her straightaway speed for the week of June 21 on Lake Washington.
By June 19 there was hurried, intense activity at the boathouse of Sayres' new waterfront home on Lake Washington's scenic Hunt's Point. Around the big mahogany plywood hull, resting on its cradle on the boathouse floor worked Sayres' full team, tuning up the boat for its assault on the barriers of time and space.
The boat's rudder had been bent when the designer, Ted Jones, had tried a racing turn at 110 miles an hour, and the new rudder, which was installed on June 18, created a dangerous flutter at high speed. The rudder was removed and taken across the lake for rework, a slow, painstaking and delaying process.
During this interval of time the anxiety and waiting was working a terrific strain on Sayres as he paced the dock at the boathouse. "I've been saying for the last few months that we can make a new record only if everything goes right. I still have my fingers crossed," he told the little group of spectators which included equipment and racing men who had come from points as far away as California to see the trial ...
When Kent Hitchcock finished his day's work in setting up his timing equipment and rechecking the course for the time trial off Sand Point Naval Air Station, he drove across Lake Washington's floating concrete bridge to Sayres' residence. "As we say out West," he said, "we had a tolerable trip up the coast." He had driven to Seattle with Mrs. Hitchcock and their young son and daughter.
Jerry Bryant, chairman of the Seattle Seafair which sponsored the time trials, had also arrived and was worriedly watching the operation on the Slo-Mo-Shun IV. "Do you know what Hitchcock asked for as soon as he got into town?" he said. "A shovel and a pick and an axe to set up the markers."
It was around dinner time, although nobody ate, when the rework on the rudder was accomplished and reinstalled on the boat. The Slo-Mo-Shun IV was hoisted from her cradle and run on an overhead track to be lowered into the lake. Sayres and Jones strapped on their life jackets and helmets, started the engine with a thundering roar, and in a few seconds the boat was a diminishing dot in the distance, trailed by a gleaming plumage of white spray.
After a short run they returned with smiles. "The new rudder is now a success," Sayres announced to his worried pit crew. "It handles so easily it's like no rudder at all, even at fast turns."
"But we've got something else to worry about," said Jones. "We also learned that we have engine trouble. Low rpm."
This could mean real trouble. The team put in another all night session checking the component parts for the engine in order to discover the cause of the baffling loss of power.
An early morning report on June 20 from Sayre's boat house indicated that the trouble had been corrected by resetting the magneto timing and using lower octane gasoline. A check run proved the diagnoses correct and the Slo-Mo-Shun IV was in top form, with her power plant running perfectly and her rudder and controls in better shape than ever. Sayres and his team were again smiling and confident, for it looked for the moment that all of their troubles were over except for the persistent south wind that was roughing up the lake.
"The record we want to break," Sayres told a reporter, "is Sir Malcolm Campbell's 141.74 miles an hour, established by Blue Bird II in England in 1939. This would give us the U. S. record, too, which is 127.063 miles an hour, set by Dan Arena in Such Crust I last August, and the North American Record, 138.645 miles an hour, set in Ontario last October by Harold Wilson in Miss Canada IV."
The south wind, which had persisted during June 21 and 22, began to falter, and on June 23 weather predictions indicated favorable water, although the surface of the lake was still agitated.
When the news flash came that Sayres might run his Slo-Mo-Shun IV shortly after noon that day, all the fast boat men who could get away from their work were on the shore, wharves and bleachers along the official course at the Naval Air Station by noon. Swells were still running in the lake, however, and the appearance of the beamy 28-foot boat was delayed.
Kent Hitchcock, in speaking over a Seattle radio from his position at the north marker, explained that the timing watch that he used had an error of 4/10 of 1 second in four hours, which in a speed run involving 24 seconds, would make an error of 1/4000 of 1 mile an hour, an immeasurable amount.
The sights, he explained, were located at each end of the statute mile set up by the city of Seattle and the Naval Air Station. The equipment was connected by a telephone cable, which was also used by Hitchcock to talk to the timer at the south marker, Ken Ludlum of Newport Beach, California. The cable also coordinated the electric timing equipment. Art Shorey, a Seattle man, was timer on the north marker.
The Crocker timer was used by the timer official following the boat through a two-power scope sight. As the boat crosses the starting line with the scope trained upon it, the Crocker timer automatically registers the start and finish, Hitchcock explained.
The wind failed to subside as the weather man promised and a ground swell lingered. But finally the Slo-Mo-Shun IV did appear, streaking: across the lake from the Hunt’s Point boathouse. After Sayres held a conference with Hitchcock, it was decided to postpone the official run until later, but it was agreed to make a run over the course at 120 mph in order to check the timing equipment.
Slo-Mo-Shun IV made a wide circle, almost disappearing in the distance, and a few moments later '` streaked over the mile course.
"Thirty seconds flat," said Hitchcock.
By 6 p. m. the many spectators who missed lunch to see the world record broken were now missing their dinners. The water was still choppy, partly from wind and partly from swells caused by spectator craft which were thronging offshore as the result of the announcement that the big boat was going to try again around 6 p. m.
"Isn't he ever going to make the run?" someone asked Kent Hitchcock. "How long did Sir Malcolm Campbell have to wait?"
With Jones riding as co-pilot, Sayres finally wound up the Slo-Mo-Shun IV and came roaring over the course at his first official try. The prop wash was flung behind in rapid soaring jets and the spectators crowded to the shore and held their breath. But they hadn't gone more than 100 yards past the starting line when the boat leaped from the water, yawed wildly, rocking on her sponsons, but came down under control to settle to a stop.
Len Ivey raced out to the stalled Slo-Mo-Shun IV in a committee boat. He was quickly back with the report that the Slo-Mo-Shun IV had lost her propeller and perhaps broken her 1⅛-inch Monel shaft.
Among the spectators along the shore was Hi Johnson, Newport Beach propeller manufacturer, who had supplied the propeller on Sayres' boat. "I'm not worried," he said. "Sayres has two more of my propellers and another shaft."
Later reports indicated that the Slo-Mo-Shun IV had hit a boat swell and left the water momentarily. The impact of the propeller reengaging the water had sheared off the end of the shaft. The sturdy bottom had resisted the shattering impact of the propeller. Little other damage was done, and Sayres' team again went to work during a night session and made the new installation of the shaft and propeller.
"I am certainly enthusiastic about the stability of the hull after that experience," Sayres said later. "In a lot of boats a mishap like that would be very serious."
On the following day, Saturday, June 24, the south wind was again rampant arid although Sayres' crew was alerted all day for a possible shift in the wind, it never came, and the time limit for the trials was running out. However, Kent Hitchcock asked for and obtained a four-day extension. It was decided to take Sunday off to give Sayres' hardworking team a rest, while the south wind continued to rough up Lake Washington.
Monday morning, June 26, at 7 a.m., daylight time, found Lake Washington calm, with mist rising, from the far shores. There was only a gentle ripple on the lake's smooth surface. With Sayres at the helm and Jones riding in the bucket seat beside him, they made a run over the course. But the timing mechanism became momentarily disconnected, and the run was lost. Sayres and Jones later reported that was the fastest run they made.
Sayres made another start from the south, covering the course in 21.98 seconds. He then refueled from his runabout, Seaflow II, a 50 mph Hacker-built job, and then went over the course from the north, Covering the distance in 22.95 seconds.
A few minutes computation by R. P. Fredericks and Mrs. Kent Hitchcock, who were the official scorers, and it was announced that the new world record for unlimited hydroplanes was 160.3235 mph, pending acceptance by the American Power t Association and the Union of International Motorboating.
"When we make a high speed run as the one over the mile course, the effect of the sponsons shattering tops of the small waves sets up minute vibration throughout the boat," Jones commented. "This vibration shakes the brain and the eyes and makes it hard to concentrate. A reference marker along the shore, such as a prominent white house, becomes a flickering blob of white that blurs up into the sky. However, the boat is very easy riding and , easy to control. When we hit that well Friday that broke our shaft, we were jarred out of our seats by the impact."
Sayres, accompanied by Jones and several others of his team, was a guest of honor at the Seattle Yacht Club the Thursday following the trial, and was presented a yacht club pennant by Tom Tryer, commodore of the club.
Sayres announced his plans to ship Slo-Mo-Shun IV to Detroit in July, and participate as a representative of the Seattle Yacht Club in America's top speed boat classic. He also hopes to qualify for the Harmsworth Trophy Race in September.
For the eastern racing schedule the steering, gear ratio on the boat is being altered to give faster maneuvering on a circular race course. Outside of very minor damages when the propeller hit the bottom, the boat came through the tests in perfect condition.
"I can't give too much praise to Ted Jones for the designing' job, to Anchor Jensen for the construction, and to Don Spencer of Western Gear, and to the mechanical, crew, Mike Welch, Elmer Leninschmidt and Joe Schobert. Without their fine cooperative spirit the achievement of the Slo-Mo-Shun IV wouldn't have been possible, particularly after breaking our drive shaft on that Friday afternoon," Sayres said. Jones, Jensen, Welch, Leninschmidt and Schobert were expected to accompany Sayres to Detroit for the Gold Cup race in July.
"Jones, Jensen and I are familiar with weather conditions on the Detroit River course and know what a rugged endurance contest it is," Sayres said. "We make no predictions on our showing back there. We'll simply go and do our best. We are well aware that new boats don't win races."
Notable was the fact that the Slo-Mo-Shun IV was a Seattle product, built by the Jensen Motor Boat Company at 1417 E. Northlake on Portage Bay. The mahogany plywood was laid up to specifications by the Elliott Bay Mill Company, Seattle. The step-up gear, a vital link with the engine, was designed and built by Western Gear Works, Seattle. Many of the fittings were supplied by Spencer Aircraft Company, Seattle, who also supplied the Aeroquip Corporation flexible hoses, cable and couplings. Other suppliers included the Champion Spark Plug Company; Standard Oil Company, high-test gasoline; Sonneman & Sons, Amalie lubrication; International Nickel Company, Inc., Monel shafts; Electric Storage Battery Company, Exide batteries.
(Reprinted from Pacific Motor Boat, August 1950, pp.11-13)