The airscrews on an Avro Lancaster's engines are about 13ft (4m) across. Spinning at, say, 2,700 rpm, they constitute an awesome power saw.
Apply it to the thin alloy skin of another Lancaster and . . . it makes me cringe even to think about it. The noise alone would be terrifying.
But that is what happened at 14,000ft over Alsace when Lancaster ND968/G, AR-O "Oboe" of 460 Squadron RAAF was hit by another Lancaster, thought to have been NN766 of 103 Squadron.
NN766 crashed in a snowstorm and all seven crew were killed.
Incredibly, ND968 made it back to England, was repaired and returned to service, and indeed saw out the war.
An account of the collision appears in the RAF Memorial Flight Club's autumn journal and I was asked to create a Flight Artworks depiction of the event to span the opening two pages.
You can see what it looks like here; the proper version of the picture itself, with print options and prices, is on the Flight Artworks website here.
The account was written by the late Dave Fellowes, Legion d'Honneur, who was the rear gunner on "O for Oboe", prior to his death in June at the age of 93.
He described how – along with those in other bombers, as it turned out – his crew had chosen to climb above their briefed altitude to escape thick cloud and bad turbulence on their way to attack Munich on 7 January 1945.
They had just emerged from the cloud when there was a rending crash and the Lanc lurched violently leftwards into a downward spin.
It had been ripped apart along the trailing edge of the starboard wing, jamming the ailerons, and through the middle – obliterating the H2S radar and its dome and almost severing the whole tail section with Dave in it, which started swaying alarmingly.
Remarkably it held together as they jettisoned their bomb load, returned to England and made a long, flat, flapless approach to the emergency field at RAF Manston in Kent.
Years later Dave established that the other Lancaster was most probably NN766, PM-R of 103 Squadron, which crashed that night about 23 miles away from the estimated collision point.
Sketching out my intended composition was something I was able to do quite quickly. I already had a suitable photograph looking down onto thick clouds which I thought would perfectly frame the scene.
I also already had a Lancaster photograph at just the sort of angle I wanted, from the starboard rear quarter and a little below. What took the time was figuring out how to take this splendid machine and rip it open.
I worked on the ailerons and flaps first, creating just enough of the internal mechanism in Photoshop to enable it to be seen through torn fabric and metal, then using what is known as the warp tool to twist it out of alignment, and using the built-in brushes to rip the edges of the metal. While awful to contemplate in real life, this was rather enjoyable to do on screen.
By far the bigger problem was how to portray the interior of the Lancaster fuselage from an angle that normally you cannot see because it is behind the outer skin and the radome suspended below the mid-upper gun turret.
The last time I visited the BBMF at RAF Coningsby I had taken a couple of photographs of the interior of their Lancaster, PA474. So I knew what it looked like – but from the wrong angle to use in my compilation.
Happily I was able to get their publications editor, Clive Rowley, who had commissioned the picture, to go and stick his camera in from the rear crew door to give me a better idea of the required perspective.
Once I had it clearer in my mind's eye, I then basically built the various pieces of equipment either by adapting the pictures to hand or simply creating elements from scratch - such as the outer and inner parts of the H2S radome, the ribs that frame the aircraft, and the pipework, wires, ammo boxes and runs.
There was also the lower portion of the mid-upper turret to be glimpsed. Its occupant that night was Sgt Ken De La Mare. After exclaiming that the floor below him had gone and the starboard side of the fuselage was missing for about 10 feet, Ken was helped out by the wireless operator, Flt Sgt J Wilson, and moved forward to the "relative safety" of the flight deck.
During this whole process I realised that the damage must have gone through the main joint between the centre and rear sections of the aircraft, which forms a ring just aft of the mid-upper turret. No wonder the tail was swaying.
The "G" suffix that ND968's serial number at the time was a security symbol: it carried the secret AGLT radar equipment on the rear turret, codenamed "Village Inn".
From my point of view this presented essentially another, smaller radome and mounting brackets, and I simply painted these on between and below the spent ammunition chutes on the FN-20 turret with its four Browning .303 machine guns. I made a point of checking that "Oboe" did not have the later, Rose turret with its two heavier weapons.
And then – it was night time. With these wartime operation pictures there just is no satisfactorily realistic way to portray a black aircraft at night so that you can see anything.
Before starting work I had checked that my Artistic Licence permit was still current so, under the pretext that there was quite a lot of moonlight, I splashed light onto the airframe in such a way as to highlight key aspects of the outline.
My rationale for being able to see the interior at all, having done so much work to create it, was that the moonbeams were coming in through the dinghy hatches and gun turret on the top of the fuselage.
I was pleased with the picture, but just to add a sense of drama and dynamism I scattered some debris around, coming off the wing, torn fuselage and smashed H2S. In reality this would probably already have dispersed, but we liked the effect so it stayed in.
And there you have it: a portrayal of a subject I had had in mind for some time, since reading about the fear that stalked bomber crews (one of many) of the risk of collisions in a loose formation of heavy aircraft flying at night, often in reduced visibility and poor weather, without proximity warning radars.
I hope it stands as a tribute to their bravery and to the sacrifice of the seven men who did not come back from this particular encounter.
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