HydroStream Viper


  • Boat Type: 4 Passenger, Vee-Pad Runabout
  • Length: 15'
  • Beam: 89"
  • Transom Height: 23" 1977 and prior, 21-3/4" after
  • Recommended HP: 50 - 120
  • Seating: 2 Buckets and Rear Bench (1978 and older models had back to back front seats and no rear bench)
  • Approximate Weight: 570 lbs


The Viper was developed from 1971 - 1972.  It evolved from the highly successful Vector model. In Howard Pipkorn's own words, "we took the Vector, bobbed off a couple of feet from the nose, and lopped off the rear corners to get the boat to conform to Class E sport boat racing."  It obviously worked, Pipkorn took the 1977 World Championship in Class E sport boat racing.  The deck design got a makeover too.

Howard's brother, an artist, was impressed by the design of the YF-102A Delta Dagger fighter jet so he sketched up a concept design which was influenced by the flared wings of the Delta.

Taking it one step further, Pipkorn utilized a concave shape in the bow area which not only looked good, but also added strength and continued the tremendously strong hull design. "I wanted to create a style that was recognizable from across the lake.  With one look I wanted you to know that it was a HydroStream," Pipkorn said.

In 1975, the Viper hull underwent some design changes. Prior to '75, the splashwell area had a different configuration, the pad did not have the usual hook (actually a wedge) in the back, there was no flotation, and the "wing"/chine area had a narrower profile. Unofficially it was known as a Viper I prior to '75, and the Viper II after that. See the Vector model page for more discussion on the design change and the hook.


Pre 1975 Post 1975


75 Viper - Boat House Bulletin (Mercury Marine)