Water-ski racing authorities should consider capping speeds after the "tragic death" of a champion observer on NSW's Hawkesbury River, a coroner says.
Victorian father-of-four Ian Baker died after his superclass boat The Ringmaster flipped while travelling at 187 km/h during a qualification event, the day before the 2014 Bridge to Bridge Ski Race.
Deputy State Coroner Teresa O'Sullivan told the Glebe Coroner's Court calls for a speed limit from the sport's participants had been a "striking feature" of the inquest.
She recommended Ski Racing Australia consider possible speed restrictions in the unlimited and super-class categories and that Roads and Maritime Service look at whether speed limits should be part of aquatic licences for the Bridge to Bridge Water Ski Classic.
"Speed contributed to Ian's death," Ms O'Sullivan said in written findings on Monday.
"The boat could not have become hydro-dynamically unstable, whether as a result of speed alone or impact with an object, unless it was travelling at an excessive speed."
During the inquest, The Ringmaster's driver Daniel McMahon said the crash that killed his good friend was so violent and rapid that he thought he had fallen through the bottom of the boat.
He, other crew members and an expert believed the vessel had hit something in the water.
But marine investigator Nayland Aldridge told the inquest the crash could have happened when the bow entered the water and propeller torque took control at high speed.
"I am not able to prefer one expert witness over the other as each opinion was equally plausible," Ms O'Sullivan said.
"Accordingly, I cannot find, on the balance of probabilities, what caused The Ringmaster to lose control and crash."
Mr Baker's death came a year after a fatal Bridge to Bridge crash involving champion skier Sarah Teelow in 2013.
Among Ms O'Sullivan's other recommendations, was that Ski Racing Australia consider requiring all vessels to carry spinal boards, defibrillators and neck braces.
She also said the authority should look at whether a net or cage could be used to collect debris beneath the water.
Mr Baker's wife, Joanne, did not speak to reporters as she left the court on Monday.
"Ski racing was one of Ian's passions and tragically it took him from us," she said in words read out by Ms O'Sullivan.
"However his biggest passion was his family."