Businessman, inventor and pilot who helped teach Prince Philip to fly;

Born: March 12, 1918; Died: January 28, 2013.

GERRY Harris, who has died aged 94, was an engineer and businessman who, later in life, invented a water spraying system which was so economical it could extinguish a fire with one pint of water.

His hydro-mechanical method of injecting water vapour and tiny water globules into a free-flowing jet stream also had positive implications for agriculture and golf course management, particularly in arid countries.

Mr Harris, who was in his 70s when he developed his Spinstat water jet, intended it to be used for irrigation and forestry. The system, which worked a little like a soda siphon, earned him a John Logie Baird Award for Innovation. It also attracted the interest of fire equipment manufacturers because of its effect on flames. It could put out a 6ft oil-fed flame in two seconds using less water than a teapot could hold.

Gerry Harris was born in Whitecraigs, Glasgow, the son of Joe and Esther Harris. His father taught business studies and founded his own menswear retailer, Ger-Alds of Glasgow.

Gerry was educated at Glasgow Academy. After leaving school he enlisted in the Fleet Air Arm where he trained as a pilot. He served in the Pacific during the Second World War and it was while stationed in Australia he had the privilege of helping a dashing young RN officer learn to fly.

That officer was Prince Philip and, years later, he was to remember Mr Harris when he presented him with his John Logie Baird Award.

After the war he returned to Scotland and resumed his courtship of his childhood sweetheart, Patricia. They married in 1950 by which time he had gained a degree in mechanical handling and engineering.

He and Pat moved to Troon where they were to live for the rest of their married lives. Mr Harris started his own successful engineering business, the Ayrshire Elevator Company, which was based in Hurlford, near Kilmarnock. He made mechanical-handling elevators, repaired tractors and built trailers. His talent for designing and making innovative farm equipment earned him a host of medals at agricultural shows.

Some years later he took a different business direction when he branched out into high street retail, taking over his father's Ger-Ald's menswear stores. He built the group up and soon had seven branches in Glasgow and Ayr.

Mr Harris retired from his business interests in the early 1990s, a move which allowed him to pursue his interest in inventing. He was driven by a desire to create machines which would not only improve the quality of life but help to save lives.

His biggest success was the Spinstat water jet, a turbine-based system which disseminated water in an extremely effective and economical way.

He was a life-long sailor – he had his Master's Certificate – and was most at home in the waters of the Firth of Clyde.

He also retained the pilot's licence he gained during his military service and enjoyed flying small aircraft from Prestwick airport.

Mr Harris is survived by his wife, children, Richard, Jane and Timmy, four grandchildren and two great grandchildren.