In the summer of 1978 two former members of a B-17 crew met to discuss their escape from death in a raid on Kassel in Germany in 1943.

Sitting on a porch in Tarrytown, New York, co-pilot Bohn Fawkes turned to his navigator Elmer “Benny” Bendiner and said: “You remember that we were hit with 20-mm shells?”

Benny said that of course he did but that was not unusual. It happened whenever they got jumped by a German fighter.

Bohn leaned forward and Bendiner could see that a “revelation was on the verge”.

Yes, but remember the shell that hit the gas tank? Bohn said.

Benny said he did. All the crew had talked about it like it was a miracle. And to them it was, because somehow their plane – Tondelayo – had not been blown out of the sky by an explosion. Just unbelievable luck, they assumed, and carried on with their duties.

That’s not quite the full story, Bohn told him now, 35 years later. He said the morning after the raid he’d checked with the ground crew and was told there had been not one but 11 unexploded shells in the gas tank.

Eleven unexploded shells in the fuel when just one should have been enough to blow the B-17 apart.

Bohn said the shells had been sent to the armorers to be defused but had then been rushed away by an intelligence officer.

Bohn had tracked down the officer and had hounded him until eventually he had told Bohn the full story – before swearing him to secrecy.

Bohn wanted to tell his old friend now.

He said that as the armourers had opened each shell they had found no explosive charge. Each shell was empty, harmless.

Except one. Inside that one was a carefully rolled piece of paper with a note written in Czech by a labourer forced to make the shells for the Luftwaffe.

The note said: “This is all we can do for you now.”

The crews’ lives had been saved by someone they would never know. And the worker would never know that he/she had saved ten lives.

I came across this story in Elmer Bendiner’s marvellous 1980 memoir, The Fall of the Fortresses, while researching the lives of USAAF crews flying out of England during WW2.

It stopped me in my tracks but nothing prepared me for the reaction it would get when I shared it on Twitter (1.25m people have read it so far). The actions of a hero risking their lives to help someone they would never know struck a chord.

For some people it found a new relevance in these days of the Covid-19 pandemic when we are all being asked to stay inside to save the lives of others – perhaps strangers – across society. But it also set me thinking about other instances where sabotage might have helped aircrew – sabotage not by trained agents of the OSS or SOE but by foreign labourers forced to work for the Nazis. It’s an immensely difficult area to research. Such sabotage was naturally secretive, and many would not survive to tell the tale.

It was also possible for myth to develop. For instance, it has been claimed the note in Bendiner’s story also included the words: “Using Jewish slave labour is never a good idea.” But these words are not in Bendiner’s original account in his book.

The Nazis put the use of forced labour at the heart of its war industries. They gathered up huge numbers from territories over-run in eastern Europe and Russia, but also from the Netherlands, Belgium and France, where round-ups would encourage many young men to join resistance groups.

According to Nicolas Stargardt in The German War, there were just under 8 million foreign workers in Germany by the summer of 1944. Huge numbers worked in agriculture and on the railways but it was factories which would become the focus of resistance and sabotage.

In Defying Hitler I wrote about some of the 500 Jewish people of Berlin who were forced to work at Siemens-Schuckertwerke, an aircraft parts factory which spread across a two-hundred-acre site in the northwest of the city. The workforce contained at least two groups of anti-fascists, led by the inspirational Herbert Baum, the jazz musician Heinz Joachim, and a young toolmaker named Heinz Birnbaum. All had actively opposed the Nazis since before they even came to power and would coalesce as a single resistance group under Baum.

Baum and Joachim spread anti-Nazi feeling and encouraged dissent, while as a sub-foreman Birnbaum worked out which of the workers might help him carry out small acts of sabotage: pouring sugar into a machine’s transmission to make it seize up and change the measurements on a job ensuring it had to be done again. These things could only be done sparingly and not repeated by the same person so Birnbaum took care to recruit as many helpers as he could.

Baum and his French Catholic friend, Suzanne Wesse, also wrote pamphlets encouraging sabotage and such was their success that Baum teamed up with Robert Uhrig, a thirty-eight-year-old toolmaker who controlled a large factory-based resistance network of his own, carrying out small acts of sabotage at factories in a number of cities, including Hamburg and Essen. He concentrated on infiltrating workers – mostly non-Jews – into armaments and aircraft factories.

Both the Baum and Uhrig groups were eventually uncovered and huge numbers were executed. With the urgent need for fighters to defend the Reich, German aircraft factories demanded full commitment from the forced labourers it treated badly and fed poorly. And so one of the most basic forms of resistance a worker could do was to slow down the pace of work.

According to Detlev J.K Peukert’s Inside Nazi Germany this may have become widespread and, while it was usually punished as ‘idling’, it often became viewed as sabotage. Every month the Reich compiled statistics for the numbers of arrests and foreign workers made up the largest category.

Peukart uses just one month of the war – December 1941 – to highlight the situation inside Germany, at a time when the number of foreign workers was about a third what it would be by the time of D-Day.

During that single month the Gestapo recorded 7,408 arrests for refusal to work and another 2,043 for ‘opposition’.

These are nameless people now, who downed tools in a state which allowed no opposition, and who through their own principled dissent carried out an act of resistance. The Czech worker who sabotaged the shells which struck Bendiner’s aircraft might have hoped and prayed that their failure to fill the 20mm shells would save an Allied airman but they probably never imagined their note would be discovered.

If it was a miracle that the B-17 survived, it was also a miracle that this wonderful act of humanity was revealed. And so we are left to wonder if this brave and nameless individual also became a statistic in a Gestapo report? For arrest, deportation to a concentration camp, death? We are allowed to hope they survived but we will never know. Either way, they are a symbol of all those who show courage without expecting reward or recognition.