It was noisy, hot and tiring work - but it had to be done.

The workers at the Hillington plant in Glasgow were producing the Merlin engines for the Spitfire.

MARK SMITH discovers more about the vital work of these dedicated women – and a few men.

Ken Milne remembers the plant well. He arrived to work there when he was 16, and his first impression was the size of the place.

The room he worked in building engines for the Spitfire was about half the size of Hampden, and was filled with around 1000 people, most of them women.

Ken’s shift started at 7am and went on until seven at night and he was standing all the time. “It was exhausting,” he says, “but it was also exciting. I knew how important the Merlin engine was, and I was proud to be working on it.”

Ken, 84, who is originally from Shettleston, also remembers the noise: “There was the constant noise of machinery. It was pretty much working 24 hours a day. The only time they were silent was during lunch and the short tea breaks which you had to take standing by your machine.”

Ken was one of 25,000 staff who were working at Hillington at its peak, and 70% were women.

And if you didn’t work there, you knew someone who did.

Leo McKinstry, the author of Spitfire: Portrait of a Legend, said the Merlin was central to the success of the Spitfire and its victory over the German Messerschmitt during the Battle of Britain.

The 70th anniversary of the battle is being celebrated this month, and Leo said the Spitfire deserves to be celebrated for the central role it played.

“First of all, the plane is aesthetically very beautiful,” he says. “It’s got wonderful lines. It was fast and beautiful to look at. Its designer, Reginald Mitchell, was a wonderful mixture of the artist and the engineer.

“Pilots said it almost felt part of them when they sat in the cockpit, that there was this unique conjunction between man and plane.

“It also has tremendous resonance because it became a symbol of Britain’s defiance and saving us in 1940. There’s no doubt that if the Battle of Britain had been lost, Hitler could have invaded Britain if he wanted and the whole history of the world might have been different.”

The first prototype of the Spitfire flew in March 1936 – it weighted 1000 pounds less than the Hurricane and went 39mph faster – and Leo said there was a deliberate campaign in 1940 to make the Spitfire the symbol of hope and defiance.

“There was a lot of propaganda featuring the Spitfire commanders, there were Spitfire funds to raise funds. There were no Hurricane funds or Lancaster funds.

“There may have been more Hurricanes, but it was the Spitfire that played a role in boosting morale. 1940 was the Spitfire summer.”

One problem was that the Spitfire was a very advanced plane and complicated to build, but by 1942, Hillington was producing 400 engines a week, including those they repaired and overhauled.

By the end of the war, they had produced 24,000 of them.

Historian Peter Sherrard, of the Rolls Royce Heritage Trust, said it was a remarkable achievement.

“They had to start from scratch and started training people in 1938,” he says.

“At one time, if you had gone into one of the big machine sheds, it would have been 70% women who were trained in just three weeks. It would have been hot, sweaty and dirty.

“They started on 12-hour shifts, seven days a week, and it wasn’t until they started dropping like flies that the Ministry said ‘You’ve got to give these people a break.

“So they were given half a day off once a month before eventually going on to a 54-hour week.”

The Air Ministry had found the site, paid for it and opened it, and Rolls-Royce ran the place for the Ministry.

There is no question that it played a huge role in eventual victory.

“The Merlin gave us the edge over the Messerschmitt,” says Peter Sherrard. “It is recognised as the best engine of any involved in the conflict.”

Jeremy Crang, a historian at Edinburgh University who specialises in the Second World War, agrees with this analysis that the huge machinery at Hillington – and the thousands of women and men who operated it seven days a week –helped us win the war.

“What was also important was that the British aircraft industry was outproducing the German factories,” says Crang.

And then of course there was the morale-boosting effect of the Spitfires rolling off the production line.

The workers loved them, the nation loved them and, perhaps most importantly, the pilots loved them.

“The spitfire is an icon,” says Nigel Rose, one of the last surviving pilots to have flown with 602 City of Glasgow Squadron during the Battle of Britain. “I saw the first few Spitfires as they came off the production line and the appeal is really universal – it really is the most amazing plane.”

602 SQUADRON: FACTFILE

• It was formed at Renfrew in 1925 as an auxiliary squadron.
• In May 1939, it became the first squadron to receive the new Spitfires. One of their planes now hangs from the ceiling at Kelvingrove.
• 602 had one of the highest kill rates of the Spitfire squadrons – and the least number of casualties.
• They shot down 89 enemy aircraft during the Second World War.
• The squadron was stood down in March 1957 before being reformed in 2006 to provide manpower to support air operations in the RAF.