SEVENTY years ago, a fateful 14 minutes turned William McMullen into a war hero.

One minute he was at the controls of his Lancaster bomber, returning to his Second World War airfield after a routine training flight; the next minute, his engine was on fire, his crew were baling out and he had a split second decision to make: should he follow them out of the door and parachute to safety, or should he stay with his stricken craft and attempt to steer it away from the hundreds of houses beneath him?

"It's only me for it," he said to the last crew member to jump. "There are thousands down below."

In his last minutes, Pilot Officer McMullen succeeded in guiding his plane over the rooftops of the east end of Darlington before crashing into a field, killing himself instantaneously.

The mayor of Darlington wrote to his widow at home in Canada. He said: "For sheer self-sacrificing heroism, your husband's action will be remembered and honoured by the people of Darlington for years to come.”

And so they are. At 8.49pm on Tuesday, the current mayor of Darlington will lay a grateful wreath and say a thankful prayer beside the field in which McMullen had died in that minute 70 years earlier. All are welcome to attend the ceremony which won’t be hard to find – it is in the road which bears his name.

McMullen had probably been born in Toronto in 1912 – “probably” because when he died in distant Darlington, his age was variously reported as being 29 or 33. Ever since he had been young, McMullen had loved flying – after school, he’d worked as a sales representative for Coca Cola and then as a driller in a goldmine in British Columbia, spending his spare pennies on flying lessons.

But at the start of the war, he was pushing 30 – and only young men were being considered to train as pilots. In 1940, on his application form to join the Royal Canadian Air Force, he seems to have manipulated his age so that he appeared younger, and he wrote: "There is nothing I would like better than to be in the air force and see some action."

His daughter, Donna, who was five when he died, said on the 40th anniversary of his death: "He claimed that he was born in 1915 because of the age restrictions on pilots but he would have been older than that. I'm not sure of his real age even today.”

His nickname among the aircrew was "Grandad".

McMullen won his wings in November 1942 and in 1944 left his wife, Thelma, and daughter Donna and came to England to learn to fly Lancaster bombers. He acquired his six-man crew in August when they baled out of their burning Lancaster at 5,000ft over France, their pilot breaking his leg as he landed.

On Christmas Eve, the new team – all Canadians – was posted to RAF Goosepool at Middleton St. George. They joined 428 Squadron – nicknamed "Ghost" and with the motto "usque ad finem" (“to the very end”). On Saturday, January 13, as they hadn’t been on a mission for three weeks, they were sent on a three-hour cross-country navigation exercise to keep them sharp.

They set out at 5.47pm, just as the daylight was fading, aboard Lancaster KB793. It was all routine radar stuff carried out at 10,000ft over the North York Moors. At 8.35pm, exercise over, McMullen called Goosepool for “joining instructions”. He was told visibility was 3,500ft, that there was a thin layer of cloud at 1,800ft and there was an 11mph North-North-East wind on landing – good conditions and he’d be touching down within ten minutes.

He instructed his engineer, Sgt “Lew” Lewellin, to keep the engines at 1,950rpm so the descent speed would be 200mph, and Lewellin wrote in his log: “All temperatures and pressures normal. All four engines running evenly.”

But there was a fault developing in the outer port Rolls Royce Merlin engine. Flight Sgt Steve Ratsoy, the wireless operator who was further down the fuselage, reported that it was emitting a shower of sparks and was glowing red. McMullen ordered Lewellin to press the feathering button to close it down.

As he did so, Ratsoy reported that a sheet of flame shot from the engine, that the red glow was spreading along the wing and that there now appeared to be flames licking at the engine cover.

It later transpired that the feathering pipe was not protected against fire and had already burned away. Therefore, when Lewellin pressed the button to shut the engine down, he was actually forcing oil out of the pipe so that it fell onto the red hot surfaces, causing the sheet of flame. Rather than stopping the fire, he was pouring oil onto it...

At 2,500ft over Acklam, with three engines still working and McMullen still in control of the plane, he gave the order to abandon the aircraft. Jump, jump, jump...

The bomb-aimer, Flt Sgt H Simms, was first out through the nose hatch, followed by the navigator, Flight Officer Bill Sage. Flt Sgt Ratsoy and the mid-upper gunner, Flt Sgt Ted Dykes, went through the main door, and the rear gunner, Flt Sgt John Feeley, exited directly from his turret. All their parachutes worked, and they drifted downwards along what became the A66 between Elton and Sadberge.

At 600ft, engineer Lewellin was last to leave. As he stood by the main door, he looked over to McMullen at the controls. Whether McMullen really did utter the heroic last words that were ascribed to him in the following Monday’s Northern Despatch newspaper –"It's only me for it. There are thousands down below" – is known only by the propaganda department at the Air Ministry.

The official accident report said that in response to Lewellin’s question, McMullen said: “Yes, go on, get out, I’m right behind you...”

But he wasn’t. He could have been. He could have made it to safety – Lewellin landed unscathed 500 yards from the crash site – but in that split second, he chose to remain.

He would have seen Darlington - population 80,000 - laid out before him. He might even have seen hundreds of Darlingtonians, drawn by the unusual sound of an engine in trouble, rushing from their homes.

As they looked up, the Darlingtonians saw KB793 flying in broad circles above the Eastbourne district. It was still at 600ft, but the port wing was by now well ablaze. In fact, the flames were changing colour from fierce orange – burning fuel – to fatal white – burning metal.

Suddenly, the Lancaster ceased its circles and dived steeply. Its undercarriage skimmed the rooftops of the streets named after waterfowl, and having cleared the last of them on Lingfield Lane, it plunged to earth. It cartwheeled 150 yards across the field of Lingfield Farm, losing various bits of flaming fuselage as it went, its fuel tanks exploding vividly and its bullets dancing like firecrackers. The hay and oats in the farm's Dutch barn caught hold immediately and blazed brightly, illuminating the parachutes of McMullen’s colleagues as they drifted slowly down to safety.

The pilot was dead, killed on impact. He'd been catapulted, still strapped to his seat, 120 yards out of the windscreen, but his flying boots were found later in the aircraft, still attached to the rubber pedals in the cockpit where he had remained in those dying seconds.

Rear gunner Feeley said later that he felt McMullen hadn’t jumped because, with the plane circling, he wanted to prevent it scything through the parachutes as they fell to earth.

All Darlington was convinced McMullen hadn’t jumped because he wanted to save them. Because his name was not released for some weeks, they christened him the “Gallant Airman”, and they wrote to the Despatch – Darlington’s evening newspaper – praising him. W Cooper of Bondgate said “he deliberately gave his life, thereby preventing the endangering of life and property in Darlington”; AF West of Gladstone Street applauded his “noble action”, and Jeffrey Dixon of Rosebery Street said he was “a dauntless man who sacrificed himself willingly to save others’ lives”.

The official accident report said that a mechanical fault in a piston had caused the initial fire, and it concluded: "From the evidence given, it is considered that the pilot and crew in this emergency carried out their duties to the best of their ability. It is also noted that the pilot retained control of the aircraft sufficiently long enough to avoid crashing into the built-up area of Darlington."

Still unknown to the public, the pilot was buried in Stonefall Cemetery in Harrogate on January 18. The service was attended by five of his six crew members. Only Dykes wasn’t there as he’d sprained his ankle on landing – he was the incident’s one casualty beyond McMullen himself.

The town collected £1,000 for its Gallant Airman and, when his name became known, offered it to his widow and young daughter back in Canada. Thelma refused it, saying it would be best put to use in war-ravaged Britain.

A group of Darlington businessmen – The Twenty Club – sent her an ornate silver rosebowl as a symbol of the town’s appreciation, and, in recognition of the generosity, Lingfield Lane, was renamed McMullen Road.

The money endowed two children's cots at the Memorial Hospital. In September 1945, McMullen's sister, Mae, who was serving in Britain with the Canadian Red Cross, attended a dedication ceremony, and met the first children to occupy the cots: Roland Bradley, ten, of Barningham Street, and Samuel Thompson, six, of Wood Street, Barnard Castle.

Mayor Jimmy Blumer told her: "By his actions, the pilot realised that he was steering himself to certain death. Not only Darlington, but the whole of the district was stirred to profound admiration and gratitude which could not be expressed in words at this act of supreme sacrifice."

BLOB People will be gathering on Tuesday at the McMullen memorial on the corner of McMullen Road and Allington Way at about 8.30pm. All are welcome.