Stan Sayres, was an automobile salesman in a Pendleton, Oregon, agency, when first stepped into a power- boat in 1926. It was an outboard hydroplane that had just done a flip on Lake McKay, dousing its driver who, after swimming ashore, said, "I'm through with boats."


Stan took him literally, bought the craft, hauled it out of the lake and was started on a career in speed- boating that eventually carried him to the top of the heap. For five years, since that day on June 6, 1950, when Slo-mo-shun IV spead through that electronically operated trap off Sand Point at an average speed of 160-323 miles an hour, she's held the world's speed mark.


It all began to click in mid 1947 when Stan Sayres & Ted Jones got together to design a new hydroplane, to incorporate radical aircraft design principles.  After the design was complete, Stan took the drawings to Anchor Jensen to look them over and asked if he would build the new boat.




Stan Sayres - owner Slomoshun


At the time Jensen Motor Boat was very busy, building and repairing US Coast Guard and Navy vessels. Anchor told Stan that under the pressure of their current contracts, there was no way he could fit another project in at that time. And that he really didn't like the design of the boat especially the form of the sponsons.


So Ted Jones agreed that he could build the boat at his home.  However, some seven months later it became obvious Ted was not keeping pace with the tight build schedule, whereupon Stan went back to his old friend Anchor Jensen and see what he could work out.  So it was that Anchor agreed to finish building the boat at JMC.  And JMC did get the job finished in a timely fashion following the specifications set forth in the Jones design.  The boat was originally launched in October 1949, without a tail. A tail simply hadn't been developed far enough to be built.


In the early days of Hydroplane Gold Cup racing every competitor in the race had to be sponsored by a yacht club. Stan Sayres was a member of the Seattle Yacht club and they sponsored the Slo-mo-shun IV in the 1950 Gold Cup and Harmsworth trophy races, and continued to sponsor both the IV and V until they finished competing under Stan Sayres ownership


When SYC's Stan Sayres and Slo-mo IV showed up in Detroit in the summer of 1950, nobody paid much attention until he qualified for the Gold Cup Race. The win gave Sayres the right to bring the next race to his yacht club. A meeting at SYC attracted about 100 people, and the club agreed to take on the responsibility. The first chairman was Jerry Bryant, owner of the largest marina in the area and veteran outboard racer. He opened the meeting with: "We don't know the first damn thing about putting on an unlimited hydroplane race, but we are going to do it."


A Perfect Day For Speed


From July 21 to 23, 1950, due to rough water and a broken propeller, Sayres' first attempts at world record runs failed. But in the early morning hours of June 26, lake conditions, with a light chop on the water, were perfect for speed. At 5:30 a.m. boats went out along the measured one-mile course and picked up any debris they could find. At about 6:45 the course was ready and the Slo-mo-shun IV, with Sayres and crewmember Ted Jones, headed out.


On the first attempt, the timer malfunctioned. The Slo-mo-shun IV continued to the south end of the course, and turned north. Sayres opened the throttle, and the hydroplane ate up the mile in 21.98 seconds (163.785 mph). For an official speed run, rules required the boat to make a second try within 15 minutes, going in the opposite direction. The Slo-mo-shun IV refueled in seven or eight minutes. Sayres then pointed the hydroplane south and zipped over the course at 157.2 mph. The combined times were averaged to establish a speed of 160.3235 mph.




Slomoshun - under construction 



On July 7, 1952, in East Channel between Mercer Island and the mainland with Sayres again at the belm, she stepped that world mark up to 178.497 miles an hour.  Going back to 1950, Slo-mo-shun IV made her trip to Detroit. First, with Ted Jones, her designer**(see notes) at the wheel, she won the Gold Cup which now rests in the trophy case of the Seattle Yacht Club.


Two weeks later, with Lou Fageol driving in the place of Ted Jones who had broken a hand, she defended successfully the Harmsworth Trophy, the world's championship emblem, and brought that to the Seattle Yacht Club, too.  And in the four following years either Slo-mo IV (she won in '52 and '53) or So-mo V (winner in '51 and '54) shared the emblem of the speedboat championship of the United States and the world and they have remained in Seattle.


All that marvelous record started from that overturned outboard Stan Sayres picked up on Lake McKay. During the next few years he did quite a bit of outboard racing*(see Notes)himself, top speed 40 miles an hour. Not much as compared to the 178.497 miles an hour he now has driven Slo-mo IV.  But the bug had taken and when Seattle became his home, Lake Washington his constant bidder for the thrills of speed-boating, his creative mind went to work.


First came Slomoshun, a second- hand 225-cubic-inch inboard he picked up. He got speeds up to 83 miles an hour out of that one. But the competition*(see notes)during the depression years (he bought Slomoshun in 1937) was limited. She burned and sank off Sheridan Beach one day and a charred piece of a rib from her hull is all Stan Sayres has to rernind him.

Second came another used boat, named Slomo II, which turned up 91.8 in her fastest time, but still didn't meet the requirements Stan Sayres wanted.




Slomoshun - World water speed record holder 1950 - 1952



Slo-mo-shun III, with a souped-up automobile engine and a specially designed hull, came next, is still running, having been sold to an Easterner. With her Sayres got up to 96 miles*(see notes) an hour. The bug had really bitten by that time and the plan to go into a bigger and faster boat began to take form. Ted Jones, the designer*, and Anchor Jensen, the builder*, came into the picture with Sayres in 1948.


Slowly the ideas were worked over, some so radical that when experienced boat builders saw the fashioned Slo-mo-shun IV they were dumbfounded. One even swore it wasn't a boat but an airplane.  She was finished and ready for the water in October, 1949, had all her preliminary runs on Lake Washington. Slowly, the word got out that a true speed demon had been developed.


More than one Lake Washington resident and boat enthusiast gazed goggle-eyed as Slo-mo IV, her 30' high rooster tail flying behind her, sped up and down the lake.  Changes were made until perfection was reached*(see notes)and then the request for sanction for an attempt on the world mark, then held by the late Sir Malcolm Campbell, the Englishman, of 141.74 miles an hour.


On June 26 with only a handful of people on hand- the fame of the boat wasn't established as yet, nor had Seattleites awakened to the thrill of her or the whine of her marvelous Seattle-built (by Western Gear)*(see notes)gear box -she made her debut.  With Mel Crook, associate editor of Yachting, as the referee representing the American Power Boat Association, and the modern, electrically operated timing devices approved by APBA checking her, Slo-mo-shun IV startled the whole boating world.

Speedboat men looked at that 160.323 miles an hour they saw in their morning newspapers and gasped. The Sayres family, with that astounding run, were literally catapulted into a limelight they had never thought of.


To a home-loving, modest woman like Madeline Sayres it was an experience almost terrifying at times, even with her graciousness. And to Stan Sayres, actually shy to an almost self- effacing point, it was a situation that grew and grew, that placed on his shoulders not only the need to face scores of calls for talks on his great boat but correspondence and demands for photographs that kept him and two stenographers busy for weeks.




Ted Jones - designer slomoshun



Gold Cup entrants know this. But no one knows it better than a Gold Cupper named Tudor Owen Jones, a hand some, husky man of 45 with flecks of gray in his dark hair, who has had more to do with this year's Gold Cup entries than any man alive. As a young mechanic in Seattle's Boeing aircraft plant, Ted Jones conceived the original design from which virtually every one of this year's boats was copied. As chief architect for Stanley Sayres (Sports Illustrated, Aug. 23, 1954), a wealthy Seattle automobile distributor, he designed the Slo-Mo-Shuns IV and V that have won the Cup for the past five years and set two world speed records to boot; and Jones himself drove Slo-Mo IV to her first Gold Cup victory in 1950.


Victories are fine, but Ted Jones wants credit-and headlines. In the world of the Gold Cup however, the headlines go not to the designer but to the owner. In 1951, for example, Jones says Slo-Mo IV was judged the greatest mechanical design of the year and that Owner Sayres took the award, forgetting to credit his designer. Jones was furious. That year and the next, while Slo-Mo V was taking shape from Jones's design in the boatyard of Builder Anchor Jensen in Seattle, a three-cornered feud developed involving credit, authority and, of course, money.


Jones has dedicated his life to speedboat design. He began when he was a boy of 17, building first an outboard racer, then a 14-horse-power water sled that he used to run at 33 Ales per hour through the rolling wake of the passenger boats that plied between Seattle and Tacoma. He also puttered around on land with a motorcycle and a hopped-up Model T, both of which he raced.


At this point, Sayres himself was still happy, and lyric in his praise, not only of Designer Jones, but also of Race Driver Jones. "His technique," says Sayres, "is perfect. His is sound, fearless and careful, all at the same time. His reactions are instantaneous, his coordination perfect." Forthwith, be presented Jones with a brand new Chrysler from the well-stocked Sayres automobile agency. That was the end of the bouquets.




Slo-mo-shun V - U37



Just before the race Jones and Sayres had entered into a written contract, which granted Jones $500 for his work, and prevented him from designing boats for Gold Cup rivals. Jones says Sayres wanted it for tax reasons. Sayres says Jones wanted it to give himself final say in all matters of design. Neither one seems to have been very happy with it.


Again, lessening of love did not prevent the uneasy trio from planning bigger and better speedboats. No sooner was the Gold Cup brought safely to Seattle than Sayres and Jones started planning how to keep it there. Slo-Mo IV was the fastest boat in the world on a straightaway; and she turned fairly well. But if they could get a boat that would accelerate a little faster, turn a little tighter, and hold speed on a straight, Detroit would be a long time getting its cup back. Jones quit Boeing and applied himself full time to the project. The result: Slo-Mo V. 


There was one other result, a second contract, this one verbal but subsequently just as unsettling as the written document that went with Slo-Mo IV. By the terms of the agreement, Jones got a flat fee of $5,000 for his plans, plus $500 per month while working on the V at Jensen's. This arrangement seems to have made Jones feel too much like a hired hand, and not enough the man behind the boat. Nonetheless, the trio managed to hold together? long enough to see Slo-Mo V win the 1951 Gold Cup. Buts a few months later Jones left Sayres to take a $1,000-amonth traveling job with Carl Kiekhaefer, president of the company that makes the Mercury outboard motor.


Please note the above story has been complied from several opposing accounts of the Slomoshun boat, its tean and development.  We have tried to give an unbiased account, so as not to offend any surviving party or their families.  Please feel free to comment, if we have posted any material fact incorrectly.
















Speed MPH



World's Straightaway Record
(Average speed of two runs in opposite directions)

Stan Sayres

New Record




Gold Cup Race
(3 statute Mile Course)
(90 miles-3 Heats

Ted Jones

Won All 3 Heats,
New HeatRecord (80.892 mph)
New RaceRecord (78.215 mph)




The Harmsworth or British
International Trophy
(5 nautical mile Course)
(90 N. Miles-Two heats)

Lou Fageol

Won-All Heats
New Lap Record (102.676 mph)
New Heat Record (100.680 mph)
New Race Record (95.623 mph)




Silver Cup Race
(Won First Heat)
(Cracked Diveshaft)
(Out Of other heats)

Lou Fageol

Won First Heat




(5 statute Mile Course)

Stan Sayres

1 lap at (111.43 mph)
3 laps at (110.89 mph)




Seattle Seafair Trophy Race
(Fastest Time Ever Run in Competition)

Lou Fageol

Won 2nd Heat
New Lap record (112.530 mph)
New Heat record (111.742 mph)



Vancouver BC

Exhibition "Match Race IV & V"

Jones "IV"
Sayres "IV"

Jones-Won First(90.864mph) HeatSayres-Won 2nd Heat
2nd lap at (110.652 mph)




World's Straightaway Record
(Average of two runs in opposite directions)
(South run made at 185.567)

Stan Sayres

New Record




Gold Cup Race
(3 Statute Mile Course)
(90 mile-3 Heats)
(Race speed curtailed by
critical accident)


Won Two Heats
Out of Third Heat
Race Average (79.92)




Gold Cup Race
(3 3/4 Statute Mle Course)
(90 miles-3 heats)


Won all heats
Fastest Lap (104.231)
New Heat Record (95.268)
New Race Record (92.571)








Ted Jones, the man who creating the Slomoshun IV & V died in January of 2000

Ted was an extremely talented man, and some of his ideas helped change the nature of hydroplane racing forever.  For his contributions as an original member of the team that created the Slo-mo-shun IV & V and his many boats & accomplishments thereafter, he has carved out a well earned place in the hearts and minds of everyone in the world who has ever enjoyed the sport he loved so much. He will be missed and never forgotten.



Anchor Jensen, World Renowned Master Shipwright Dies in Seattle

Anchor was an artist, designer, intuitive genius, master shipwright, builder and healer of thousands of boats. Boats that went to war, boats that went to work, boats that broke world records, and won Seattleís heart and the Gold Cup 5 times. Thatís a lot to say about a man, but someone had to say it ,because he never would. A friend of Anchors told me when I asked him, "what was he like as a child"? His response was " the same as he is today , a man of few words, always thinking always working".




Anchor Jensen - builder Slomoshun



Anchor was born July 25, 1918, in Victoria British Columbia. His father Antonius (Tony) Jensen was a musician who loved boat building, his mother the beautiful and industrious daughter of a well respected Victoria doctor. Anchor, the second of two children, couldnít have been given a more appropriate name. He lived up to it every day. I realized today as I was writing this, that as I look back over his life I donít think he has ever been away from the water or a boat for more then a couple of days in his entire life. The day he was born his dad was working on the Tony Boy in the backyard of their home, When they left Victoria when Anchor was seven they didnít drive or take a train, they cruised down Puget Sound, on the Tony Boy. 


When they reached Seattle, Anchorís Family didnít move into a house they lived aboard the boat, next to the Queen City Yacht club on Portage Bay where Tony and Bessie had purchased property to build a boat yard. When Anchor started Grammar School at Seward and then Laurelhurst he commuted by boat and foot. When it came time to move off the Tony Boy, the family didnít bother to move to dry land, Tony had built them an apartment on the second floor of the first building of the Jensen boat yard, established in 1927, which was located out over the water, with a ramp leading up to dry land. When Anchor enlisted for WWII he graduated with honors at the top of his class at Great Lakes Naval Training Center and served with honor in the Navy aboard the Battleship Iowa and the USS Belleau Wood. When he married Ann Katheryn Clarke in September 1950, they went to Hawaii, God knows, they could have flown, but not Anchor they had to take a cruise ship the Lauraleane.


Anchor spent his entire life immersed in learning about boats and how they perform on water. Even yesterday when he became seriously ill he was at the boat yard. The same yard he has lived and worked at all his life. In addition to being co-designer and builder of Slo-mo-shun IV and V which set World Speed Records in 1950 and 1952 he also managed and owned the Jensen Motor Boat Company for the last 63 years. During this time they built hundreds of classic wooden custom boats and rebuilt thousands of others. Anchor was a life long member of the Mountaineers, a past member of the Seattle and Corinthian Yacht Clubs, member of the APBA and many other organizations. He is the recipient of numerous awards for his life long contribution , not only for his pioneering innovations in the world of Hydroplanes but also for his commitment and contributions to the northwest boat building community. Anchor had the perfect name and made living up to it a matter of personal pride.  He will be remembered worldwide for his creations the Slo-mo-shun IV and Slo-mo-shun V.






"Of records and record breakers, I would remind you that speed is relative to time.  What we consider slow now, was unthinkable in years gone by.  However, each time a contender goes out onto the field of battle, he or she faces the same hurdles, the same fears and financial challenges as those before us, and most importantly of all, has to muster themselves to boiling point make it all happen.  In the end, players will either triumph or fail, but in doing so, show others where to, and where not to tread.  All too often players pay the ultimate price.  Whether they raise Man's technical mastery up another notch or not, history should remember every last one of them - for they were players."  (Nelson Kruschandl December 2005)




Nelson Kruschandl











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