In his 100 years, Bill Sinclair has seen more than most.

He was there when Japanese submarines infiltrated Sydney harbour in World War II, had a bird's eye view of the D-Day conflict, was burnt out in the Ash Wednesday bushfires and built up the state's biggest regional independent accounting firms.

On Sunday, December 15 the former accountant, farmer, WWII pilot and keen sportsman will celebrate the triple-figure milestone with family and friends.

Mr Sinclair was born in 1919 on a small farm just out of Urana in New South Wales.

As one of five kids, it was his job to milk the house cow before riding his pony seven kilometres up to the road to a small school.

As one of just 35 students, Mr Sinclair said it was just like getting private tuition.

He left school at 14 to train to be an accountant, and with the Great Depression hitting his family hard, left home to live with an accountant in Temora.

He said that working with farmers in the wake of the Depression taught him a lot about hardships.

After being knocked back by the air force on medical grounds, Mr Sinclair joined the army and was an instrument operator on "the big guns" at North Head in Manly during WWII.

He happened to be on guard duty the night the Japanese midget submarines infiltrated Sydney Harbour.

"We got a bearing on the mother submarine but the guns we were using had only ever been used with half-charges at practice," he recalled.

"If we had have got a second bearing and fired and fired a full charge we would have probably shattered half the windows in Manly."

In August 1942 he transferred to the air force and trained on Tiger Moths at Temora before being transferred to Camp Borden near Toronto in Canada for advanced training on Harvard aircraft.

By June 1943 he'd got his wings.

By the time he arrived in England, the Battle of Britain had already been won, so he was posted to Cornwall to prepare for the Battle of Normandy. D-Day was set for June 1944.

"During the Normandy invasion I was based mainly in the Bay of Bisclay for surveillance of submarines," he said.

It was precarious work where he was flying at only 2000-feet and the weather over the Atlantic Ocean had turned for the worse.

"Our specified job was to keep the submarines under the water and make it difficult for them to recharge their batteries," he said.

Mr Sinclair remembers the feeling of absolute joy and relief when in May 1945 Germany surrendered signalling the end of the European conflict.

His last operational flight of the war was in June 1945 when they went to search for the crew and passengers of a Liberator aircraft down in the Atlantic.

He and the rest of the crew decided to go on the mission despite being told Australian pilots had been grounded because otherwise there would be no plane in the search area for two hours.

"The flight lasted 12 hours and we arrived back in total darkness and it was raining....I felt a bit nervous as I pointed the nose of the plane towards the runway lights," he said.

His commander signed him off from the squadron, marking the flying log book he has kept all these years with the words "above average".

Mr Sinclair worked as an accountant in Edinburgh for a year before he was repatriated back to Australia.

He then took up work with a Melbourne firm which specialised in taxation, a job which often brought him to work in Warrnambool in 1947.

About two years later he decided to start his own business in Warrnambool which opened in early 1950, and Stan Wilson joined him in 1951.

His office was a partly demolished house behind Kermond's hamburger stand, and it took 11 years before the the firm became profitable.

To make ends meet, he would grow potatoes and gladiolus to sell, pump petrol on weekends and drove taxis.

Mr Sinclair played football with what was then called East Stars and played in five premierships with Dennington Cricket Club.

In 1953 he took up playing golf and a decade later, after successes in the Warrnambool championships, ended up playing in the Australian Open as an amateur at Royal Melbourne Golf Club.

"I had the aptitude to play golf better than any other sport but found out a bit late," he said.

Mr Sinclair helped establish the Warrnambool Golf Club and it was golf that led him to be in Melbourne when he met his wife Lydia in 1967.

He'd been there returning a golf club to a friend that day.

Mrs Sinclair had not long arrived in the country by boat from Germany in 1967 on a working holiday without speaking a word of English.

Within the first week she had two jobs, one of them in Melbourne's famous French restaurant La Popotte.

One of the tables in the restaurant was set aside for staff dinners every night and about four weeks after she started work there she arrived to find Mr Sinclair sitting there.

He was a friend of one of the other men who worked at the restaurant.

"Of course all of a sudden Mr Sinclair had to come to Melbourne very often," Mrs Sinclair said. The couple married in 1969 and this year celebrated their 50^th anniversary.

Mr Sinclair also loved farming and purchased land at Naringal that was burnt out in the Ash Wednesday bushfires.

The farm manager had saved their 75 breeding cattle. "It was an amazing effort because he had to drive them in the direction of the fire," he said.

They lost 17 young steers in the blaze, and their pony which disappeared in the fire turned up five days later without a scratch.

The couple had also purchased the Rosebank Homestead on Caramut Road in 1973 - bluestone from the demolished Woodford flour mill was used to build the house.

It was while digging up a new garden for their newly renovated house in March 1986 with a rotary hoe that they unearthed a live WWII hand grenade that had a killing range of 115 metres.

An Army bomb disposal expert had to come from Melbourne to explode it.

Mrs Sinclair, who lived through the bombing of Berlin, said when Mr Sinclair went to pick it up she quickly told him not to because it looked like a grenade. She was right.

Mrs Sinclair was just a young child when heavy bombing robbed her family of all their possessions and home.

Mr Sinclair joined Legacy in Warrnambool in 1953 and looked after the welfare of war widows for decades.

He officially retired from the business that still bears his name in June 1988. It is still one of the biggest independent accounting firms in regional Victoria with five offices and 140 staff.

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