ON March 20 1974, Bob Fulton arrived for work as usual at the Rolls-Royce factory in East Kilbride. But he noticed something out of the ordinary. A cargo of Avon aircraft engines had arrived for repair bearing Chilean insignia. They were from the Hawker Hunters that attacked Chile’s presidential palace during a right-wing coup just six months earlier. A committed Christian, Fulton refused to work on the engines. The rest of the 4,000 workers at the plant joined him in solidarity.

For four years the warplane engines lay – defiantly unworked upon – in East Kilbride, until one day they mysteriously disappeared in the middle of the night, leaving the workers in the dark for decades about what happened to them. The workers were led to believe that their actions had been meaningless, but back in Chile the Scottish boycott became a celebrated, almost mythical moment in the struggle against the ruthless Pinochet regime.

The stories of Fulton and the rest of the Rolls-Royce workers, once recounted only in whispers, were finally told in Nae Pasaran, a compelling short film by Felipe Bustos Sierra, right. Now Sierra, who was born in Belgium to exiled Chilean parents and has been based in Scotland for 10 years, is in the final straight of a campaign to crowdfund a full-length feature film version.

Sierra’s aim is simple. To tell the world – and Chile – about a vital part of the country’s history that has often been elided and neglected. “The history of Chile after the coup has not been told," he says, speaking at his Edinburgh home. "It is not even taught in schools in Chile. There is no story of the torture and the human rights abuses, there is no story of the exile, there is no story of the solidarity.”

“We have got one of the happiest stories in the history of the coup, that is very unknown in Chile where all the stories are so bleak.”

The Chilean coup, on September 11 1973, was certainly one of the most vicious episodes in a brutal decade in South America. Backed by the CIA,

Chilean army chief Augusto Pinochet toppled the democratically elected socialist government of Salvador Allende.

British-built Hawker Hunters laid siege to the presidential palace.

Allende, refusing to surrender or accept exile, made his final speech before taking his own life. A military junta was sworn in. Allende’s supporters were arrested, tortured, or forced into exile.

More than 3,000 people were killed in the first months following the coup. More than 200,000 were arrested. 30,000 people disappeared before the dictatorship finally ended in 1990.

Most global powers did little to interrupt the Pinochet regime.

Margaret Thatcher became a personal friend of the dictator after their Argentinian interests aligned during the Falklands war. But around the world many activists worked tirelessly to help the Chilean people. The Rolls-Royce boycott in East Kilbride became the longest-running single action of solidarity against Pinochet worldwide.

In March this year, Bob Fulton, who is now 92; Robert Somerville, 78; and John Keenan, 75, received the highest honour given to foreign civilians by the Chilean government, the Medal of Merit of the Order of Bernardo O’Higgins. Their solidarity had a real impact during the junta, grounding much of the Chilean air force before the engines vanished in the middle of the night in August 1978, spirited back to Chile.

“The impact they had was material – the engines were grounded in East Kilbride – but because it was such a colourful protest it also kept the story in the papers, which meant that other actions by the Chilean solidarity campaign kept getting in the papers,” says Sierra.

What stands out more than 40 years on from the Rolls-Royce protest is the power of organised labour to stand up to malfeasance thousands of miles away. “All these guys were trade unionists, all these guys were politicised,” says Sierra, who describes Bob Fulton as like a Church elder. “He heard about the abuse at church, he heard about the abuse and he knew they had the engines so he decided to act.”

The Rolls-Royce workers were not the only Scots who showed solidarity with victims of the Chilean junta. Submarines commissioned before the coup lay in Greenock for years as dockers refused to load them onto ships. The Fife mining town of Lochgelly adopted a Chilean miner.

In 1977, a boycott campaign sprang into life when the Scottish Football Association – in its infinite wisdom – decided that Scotland would be among the first sides to play at the National Stadium in Santiago, which had been used as a concentration camp in the days after the coup. Sierra has even interviewed commentator Archie MacPherson for Nae Pasaran.

Now 38, Sierra experienced the coup through the trauma it caused his family. His father was a student journalist in 1973 when, a few weeks before the overthrow of Allende, he snuck onto a ship where marines were being imprisoned. It was there that he learned first-hand about the military plan to overthrow the government. He was arrested but “was saved by the connections he had”, Sierra recalls.

On the night of the coup, soldiers went through the country daubing blue crosses on the doors of those suspected of being enemies of the new regime. Try as she might, Sierra’s grandmother could not scrub the paint off. His father was forced to flee, becoming one of the million Chileans exiled after 1973.

His father eventually made his way to Belgium, where Sierra was born.

When he tried to return to Chile, as the junta eventually fell away more than a decade and a half later, he found a very different country to the one he had left under darkness. “He was going back to a home that didn’t exist anymore,” Sierra recalls of his father.

Sierra says the military regime left Chile a very polarised place.

As well as a dictatorship, the junta was an experiment in neo-liberal economics. Acolytes of the Chicago school doyen Milton Friedman came to Santiago, treating the country as a free-market playground. The result was some of the most impressive growth rates in the continent and a vast inequality between the rich and the poor that still scars the country today.

Sierra’s message about the reality of the junta has not always been well received back in Chile. He has received social media abuse from compatriots angered by his depictions of a past that some still look back on idealistically.

“They say ‘this is bollocks’. Basically they go back into the old defences. They say you are a Communist or a Stalinist.”

But Sierra will not be deterred, saying: “My goal is to tell the truth in whatever shape it exists.” The aim of the crowdfunding campaign is to go deeper, to tell the full story of the three Rolls-Royce workers and their remarkable protest that brought the Chilean airforce to its knees.

The story of the unexpected connection between East Kilbride and Chile has a universal appeal, says Sierra. “It is just a guy who says, ‘I don’t agree with this. I’m not working on this’. I think there is a lot of power in that.”

The Nae Pasaran project is being funded through Kickstarter, and is at nearly at 60 per cent of its £50,000 target. With less than a week to go, the filmmakers need to meet their target or risk losing it all. If successful it will become the second highest funded Scottish documentary project on Kickstarter. The deadline is May 11.

www.kickstarter.com/projects/debasers/nae-pasaran-an-untold-story-of-chilean-solidarity