Thumbnail of Slo-Mo-Shun IV (1) (3793 bytes)Slo-mo-shun IV U-27 [1950-56]

"It was Stanley Sayres' Slo-mo-shun IV that made Seattle hydroplane-conscious and turned half the population of the city into unlimited hydroplane enthusiasts and fanatics. It was the Slo-mo that brought Gold Cup hydroplaning to Seattle, thus enabling 500,000 fans to witness the spectacle in their own backyards and go wild over it. During her life span, the Ted Jones-designed Slo-mo set the world's water speed record for a propeller-driven boat (it lasted five years), won three Gold Cups and the Harmsworth Trophy. It is quite understandable, therefore, that Seattleites speak fondly and reverently of the 'Grand Old Lady' and the 'Good Old Slo-mo IV'-almost as if the boat were a person. In 1956, after the battered Slo-mo IV returned to Seattle from her last Gold Cup race on the Detroit River, she was taken to a downtown parking lot. She had hit a wake during a test run, bounced and disintegrated, seriously injuring driver Joe Taggart, Although it was a weekday, hundreds of people took leave of their jobs to be on hand when she was brought in, and tears flowed freely as the canvas covering her hull was removed and the spectators viewed her broken and shapeless form, The proud beauty-now a mass of twisted wood and metal-would never race again and thousands of her loyal fans came to pay their last respects. In a few days, hundreds of dollars were contributed-unsolicited-to rebuild her, But the verdict had been handed down. She would never race again. While the boat was on display, Stanley Sayres, died-never having seen his boat in her wrecked state."

(Reprinted from This is Hydroplaning by Paul Lowney [1959])

Thumbnail of Slo-Mo-Shun IV (2) (5479 bytes)A photo of the July 1950 record mile run on Lake Washington.

"Head on, the thing suggested an amphibious flying saucer with rudder trouble. From the rear it looked like Old Faithful on a rampage. To the motorboat experts who got up at 6 a.m. one day last week in Seattle to see it perform, it looked like the fastest thing afloat.
"The 4,200-lb. monster was a mahogany-oak-duraluminum racing hull, inappropriately named Slo-mo-shun IV. At the wheel was ruddy, grey-haired Stanley St. Clair Sayres, who started tinkering with outboard motorboats twelve years ago, switched to airplanes, and switched back to speedboats when his wife made him give up flying. With the help of a Boeing aircraft engineer, he had built his flounder-shaped hydroplane to crack the world's speedboat record.
"After waiting for days for the right weather, Sayres sent his craft thundering into the measured mile, trailing a 20-ft. spume 200 yards behind. A 4-in. chop on Lake Washington provided enough lift to send the two-ton craft clipping along on her two 8-in.-square planing surfaces. Offset rudders above & below water held her squarely on course.
"On the south-north run, her Allison aircraft enging sent Slo-mo-shun screaming through the mile in 21.98 seconds [163.785 m.p.h.]. The return trip was less than a second slower [22.95 seconds; 156.86 m.p.h.]. The combination gave Sayres an average speed of 160.32 m.p.h., 18.58 m.p.h. faster than the old mark, set by Sir Malcolm Campbell's Blue Bird II in 1939.
Already looking for a more fitting name for his new world champion (current choice: Miss Seattle), Driver Sayres expects to set his next record at the Gold Cup races in Detroit later this month. Says Sayres: 'The boat was not extended.'"

(Reprinted from Time, July 10, 1950).

Thumbnail of Slo-Mo-Shun IV (3) (4903 bytes)Another photo of the 1950 mile run.
Thumbnail of Slo-Mo-Shun IV (4) (8690 bytes)It is 6 a.m., July 7, 1952 and early light shows Stanley Sayres (right) and Mike Welsch, preparing Slo-mo-shun IV for try at mile straightaway speed record on Lake Washington
Thumbnail of Slo-Mo-Shun IV (5) (4840 bytes)Setting the mile record. Mt. Rainier in background.
Thumbnail of Slo-Mo-Shun IV (6) (9656 bytes)Winning heat in 1953 Gold Cup at Lake Washington.
Thumbnail of Slo-Mo-Shun IV (7) (3332 bytes)Prop riding.
Thumbnail of Slo-Mo-Shun IV (8) (6724 bytes)Head-on shot taken from Lake Washington Floating Bridge in Seattle.
Thumbnail of Slo-Mo-Shun IV (9) (3946 bytes)"Winner of the 1950, 1952, and 1953 Gold Cup Races, Slo-mo-shun IV also set two straightaway speed records in her career: in 1950, a mile record of 160.3235 mph, and 178.497 mph in 1952. Owned by the late Stanley Sayres of Seattle, she was designed by Ted Jones and built by Jensen Boat Works of Seattle in 1949. She measures 28 feet, has an 11-foot-5-inch beam and weighs 4,750 pounds. Her colors are mahogany with red trim, and she raced for the Seattle Yacht Club. In a test run prior to the 1956 Gold Cup Race in Detroit, she hit a wake at high speed and was smashed beyond repair for racing. She has been restored for exhibition and is now in Seattle's Museum of History and Industry."

(Reprinted from This is Hydroplaning by Paul Lowney [1959])

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