Monday, 21 October 2013

The Saga of the Dornier 17

I had a rare treat last week, being invited up to RAF Cosford to take a look at the Dornier Do 17 wreck that was raised from the seabed this last summer.  It was a fascinating visit.

It was, of course, very interesting to have a tour around the workshops and see what Cosford is doing with a number of other WW2 projects: not least one of only two surviving Handley Page Hampdens - recovered from northern Russia - and a dismantled Vickers Wellington; a Heath-Robinson-esque melange of geodesic aluminium, wooden battens and tattered Irish linen...

A Dornier 17 of WW2 - shown here in Croatian colours
But the highlight was naturally the Dornier.  Shot down on 26 August 1940 over the English Channel, the Dornier Do 17 was one of around 2,000 of the light, twin-engine bomber built - known as the "Flying Pencil" for its slim fuselage - which became one of the mainstays of the Luftwaffe's tactical bombing arm.  Separated from its accompanying squadron, it seems that 5K+AR ran foul of one of the RAF's least-loved aircraft, the Boulton-Paul Defiant.  Holed across the cockpit and engines, the Dornier ditched over the Goodwin Sands, off the Kent coast, before flipping over onto its back and sinking in around 50ft of water. Two of the plane's 4 crew survived the crash and became PoWs
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The wreck remained on the Goodwin sands, apparently unknown, until the early years of the 21st Century, by which time it was thought to be the only one in existence (though the wreckage of another still litters a site near Oslo in Norway).  After a fund-raising effort, the RAF Museum finally raised the plane's remains in June 2013, and have now begun a conservation project.

As our guide explained, this is very much a 'conservation' - not a 'restoration', as it is sometimes erroneously reported.  73 years of time and tide have left little unaffected.  The Dornier's aluminium body is encrusted with barnacles and sea-life, and all of it is full of sand.  Indeed, such is the accretion of wildlife that the plane has taken on, the weight that was lifted from the seabed amounted to fully three times the weight of the original aircraft.  This material is to be removed gradually over the coming months and years.

Most pressing, however, are the accumulated chloride salts, which could cause the aluminium frame to swiftly deteriorate further.  To wash these salts away, the airframe is being constantly sprayed and washed in citric acid - at a constant pH of between 5.2 and 5.5 - so as to stabilise the remains and ensure that they can be preserved for display.  This process is, necessarily, somewhat experimental but is estimated to require around 2 years.

Some of the Dornier parts in a hydration tunnel.
As was stressed by RAF Cosford's expert, the goal at present is not 'restoration', but 'conservation', and on seeing the remains in the flesh that seems eminently sensible as any attempted rebuild - one fears - would amount to little more than a replica.  Rather, it appears that the plan is essentially to replicate the exhibit of the Handley Page Halifax W1048, which was raised from a Norwegian fjord in the 1970s, and is displayed at RAF Hendon in 'as recovered' condition.

73 years in salt water? No problem
Aside from the two hydration tunnels, much of the Dornier's ancillary parts have already been cleaned up and are meticulously boxed and labelled.  Many news outlets reported the erroneous 'fact' that the plane's tyres were still inflated when the plane was raised (they were not), but there is nonetheless much evidence among the remains of the fabled German engineering efficiency.  An 8-ft aluminium spar was handed round and was astonishingly light.. Also the bearings on this recovered gear mechanism (above right) ran as true and smooth as on the day it left the factory.  Most surprisingly perhaps, when divers decided to cut the plane's oxygen 'ring main' - the piped oxygen supply than ran throughout the aircraft - they were astonished to discover that it was still 'live'.

One hindrance that surprised me is that the plane is not complete, despite what was claimed at the time of its salvage.  A few parts - wing tips etc - had already disintegrated.  But more worryingly, it seems that in the short time between its discovery and its raising, the wreck was subjected to fairly large-scale pilfering.  As a result, most of the cockpit is missing, including the seats, controls, instrumentation and guns.  Although there is still some smaller material scattered across the sea bed, it must be assumed that most of these headline artifacts have found their way into private collections.  Consequently, an amnesty is currently in place, in the hope that RAF Cosford can secure their recovery without resorting to more forceful methods.

Having contributed - like many others - to the raising of the Dornier, it was fascinating to see it and learn about the conservation efforts.  I wish the experts of RAF Cosford every success with it, and hope that at least some of the plane's missing artifacts might one day be reunited with the plane.  If you are reading this 'private collectors' - you know who you are - do the right thing, eh?


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