A speedboat pilot has been found not guilty of manslaughter after a crash with a buoy killed a teenage passenger.

Emily Lewis, 15, suffered fatal injuries after the rigid inflatable boat (Rib) collided with the 4.5m high buoy at 36.6 knots in Southampton Water on August 22 2020, with a number of other passengers being seriously injured.

Michael Lawrence, 55, who was driving the boat, was found not guilty of manslaughter by gross negligence, but guilty of failing to maintain a proper lookout and failing to proceed at a safe speed, by the jury.

The jury took nearly 18 hours to convict Michael Howley, 52, the owner of Seadogz, the company which operated the boat trip, with not operating the boat safely.

Christine Agnew KC, prosecuting, told the trial at Winchester Crown Court that Emily’s parents, Simon and Nikki, had decided to take their daughters Emily and Amy, 18, for the “high thrills” speedboat ride.

The rib was recorded to travel at speeds of 47.8 knots, which is in excess of an expired speed limit of 40 knots (46mph) which she said both defendants believed was still in place.

As part of the ride, which took place in “perfect conditions”, the Stormforce 950 rib crossed the wake of the Red Falcon ferry five times before it then headed straight towards the North West Netley buoy, which measures 4.69m above the water line.

The Rib travelled straight towards the buoy at a speed of 36.6 knots for 14 seconds before hitting it, throwing two passengers into the water and injuring several others.

Emily suffered severe internal injuries after being crushed against the metal handle in front of her.

She was taken ashore by another Rib and then by ambulance to hospital.

She died after her family took the decision to turn off her life support system after being told by doctors that she had suffered oxygen starvation to the brain and her injuries were “unsurvivable”.

Ms Agnew said that Lawrence, of Blackfield, New Forest, initially said that a face mask had blown into his face blocking his vision but had later changed his account.

The former lifeboatman told the trial that he had lost his vision momentarily prior to hitting the buoy.

The court heard that a medical cause such as a blood clot in an artery in his eye was unlikely to have caused vision loss as it was unlikely to have affected both eyes at once.

Lawrence was said in court to be an “extremely experienced mariner” and his co-defendant described him as “Mr Safe and Mr Cautious”.

As well as serving as an RNLI lifeboatman for 20 years, he held a number of qualifications and he was also the principal of his own RYA recognised training centre, A2Sea, which held power boat courses.

Howley, of Hordle, New Forest, who is also a former lifeboatman, said that he used his experience on rescues to inform his risk assessments that he carried out for his business to ensure the safety of the passengers and staff.

Both men will be sentenced at the same court on March 17.