Last of the flying pencils: Dornier 17 bomber lifted from English Channel

Wreck of warplane brought to surface after 73 years on seabed

It was one of the most feared German bombers of the Battle of Britain. Hundreds were built in German aircraft factories n 1939 and 1940 – and their bombs devastated large areas of London, Coventry and Norwich.

The Dornier- 17 – known as ‘the flying pencil’ on account of its slender shape – was a key work-horse of the Luftwaffe in the early years of World War Two.

But only one example is known to have survived and that particular machine lay at the bottom of the English Channel until earlier this week, when it was lifted from the seabed in a £600,000 operation, led by the Royal Air Force Museum.

Over the next 18 to 24 months the museum’s experts will use new pioneering conservation techniques to try to turn the corroded, battered aircraft back into a semblance of what it would have looked like during the Battle of Britain.

But at the same time, the museum’s historians will be trying to piece together the missing bits of the plane’s history: Where precisely was it built and when? Which sorties over which British cities and airfields did it participate in? What happened to its surviving crew members after the war? Can their families now be contacted?

So far, the historians have been able, bit by bit, to piece together the story of the aircraft’s final fateful hours.

On the morning of 26 August 1940, nine Dornier bombers took off from St Trond airfield in German occupied Belgium to bomb a key RAF fighter base – Manston in Kent. But the operation had a hidden more important strategic agenda. The Germans had set a trap for the RAF. The real purpose of the raid was to lure British fighter aircraft into the air so that German fighters, quietly lying in wait, could move forward and shoot them down. The tactic was only partially successful – and the Luftwaffe lost three of its Dorniers, included the one which has just been lifted from the seabed.

That plane was intercepted by RAF Defiant fighter aircraft from Hornchurch airfield, in east London. Over Hurn Bay, Kent, it was hit by machine gun fire from one of the Defiants and crash-landed on the surface of the sea four miles off Ramsgate.

After hitting the water in an attempted controlled landing, it somersaulted and settled into the water on its back. All four crew managed to leave the aircraft. Two – 27 year old wireless operator Helmut Reinhardt and 28 year old Bomb Aimer Heinz Huhn – either drowned or were already dying from injuries sustained during the aerial dogfight or the crash-landing. Their bodies were washed up on beaches, respectively, in Holland and England, where they were eventually buried in war cemeteries.

But their two colleagues - Pilot Willi Effmert , 24, and Bomb Aimer Hermann Ritzel , 21 survived, were rescued by the British and spent the rest of the conflict in prisoner-of-war camps in the UK and later in Canada. It’s thought that both survived the war – but so far the RAF Museum has not been able to track down their relations.

For the museum – and for all those interested in the history of the Battle of Britain – the Dornier is a priceless treasure. It is not only the sole surviving example of a Dornier 17 – but is also the only surviving Luftwaffe bomber which actually fought in the skies over Britain in that desperate battle in the summer of 1940..

As well as Spitfires and Hurricanes, the museum has long held examples (all on public display) of the various types of Luftwaffe bomber used over Britain in that early part of the war – except, that is, a Dornier-17. “This was the missing link in our collection,” said Ian Thirsk, the Museum’s Head of Collections.

The other German bombers in the museum are of various aircraft types used in the Battle of Britain – but in fact date from later in the war. This newly acquired Dornier will in fact be the only German plane in the museum’s collection to have actually participated in that epic aerial confrontation.

Now the big challenge facing the museum is to prevent their newly acquired Luftwaffe prize from crumbling into dust. Usually, when aluminium has been exposed for a long period to salts (in this case, chloride from the sea) it fairly rapidly disintegrates when it eventually comes into contact with the air.

To prevent that happening, the Museum turned to scientists at Imperial College London. The first key step to ensure the plane’s future survival was to obtain samples of the metal it was made of. The college’s Department of Materials was then able to carry out tests on the fragments to determine their precise composition. But even more importantly, the scientists were then able to use trial and error to develop a perfect custom-made chemical mixture (a very specific balance of citric acid, water and sodium hydroxide) with which to treat the plane once it finally emerged out of the sea. As a result, effective conservation work was able to start virtually immediately the plane left its watery grave this past Monday evening.

The museum’s conservators also developed a pioneering new system for applying the chemical mixture. They built a special custom-made spraying tunnel, made of polythene, within which the aircraft fuselage and wings will sit for the next one and a half to two years. The aircraft will be continuously sprayed from the tunnel’s ceiling and floor.

But two other major factors have also served to help guarantee the aircraft a future. Firstly, it’s been protected by sand on the seabed for most of the past 73 years. It’s only been in recent times that changing tides and currents have removed that protective cloak. As a result if has been vulnerable to increased corrosion, the attention of looters and the impact of fishing nets.

Secondly, unlike some other planes, no copper was used to make the aluminium alloy that this particular aircraft consists of. Indeed it’s composed of an alloy which is 98% aluminium and two per cent manganese, magnesium, iron and silicon. If copper had been present, salt-induced corrosion would have been much faster – and sea life would have avoided the wrecked plane because copper is a biocide. As it was, the absence of copper allowed abundant sea life (barnacles etc) to colonize the plane and therefore in effect helped protect the Dornier from destruction.

From next week, members of the public will be able to see the Dornier undergoing conservation at the Royal Air Force Museum in Cosford, in the West Midlands. Other key Battle of Britain aircraft are on display at Cosford – and at the Museum’s other base, Colindale, north- west London

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