Beaufighter strike on "butterfly bombs" raid

Beaufighter_VI_NF_attack_Gary_Eason sm
"Moonlight Predator": Bristol Beaufighter VI

Colchester, 13 January 2018 

My most recently completed commission gives us an insight into the nature of radar-driven airborne interception in WWII, and the rapid progress in this field that had been made by British scientists.

But it also highlights the Germans' use of a sinister weapon that I had not known about until now.

It's 14 June, 1943. Bristol Beaufighter VI nightfighter V8738, WM-L of No 68 Squadron - seconded to 604 Squadron at RAF Scorton in North Yorkshire - is off the coast of Scarborough liaising with a radar station at Goldsborough, a little further up the coast.

The "Chain Home Low" radar is part of the system used to detect low-flying (down to about 500ft) Luftwaffe attackers since the Battle of Britain, two years earlier.

In the meantime however there has been a quantum leap in RAF night fighter capability. Not only is the Beaufighter equipped with its own airborne radar, it is sporting the latest Mk VIII version that has shifted up a gear into microwave frequencies, vastly improving the accuracy of the system and giving it a range of about 5.5 miles (8.9 km).

Having dispensed with the need for external aerials, this is now housed in a cone-shaped dish within the dolphin-like nose extension fitted to the Bristol Aeroplane Company's twin-engined aircraft.

The pilot, Flying Officer DB "Bernie" Wills and his navigator, Flying Officer GA "Peter" Ledeboer, have been operating at about 3,000ft above the North Sea.

At about 0130 they are suddenly diverted to try to intercept raiders approaching from the east and south-east at about 5,000ft. Their sector controller directs them for about 15 minutes then hands them back to CHL Goldsborough and a Flight Lieutenant Ross.

"I have some trade for you," he tells them, according to the secret RAF Intelligence Form F and their combat report, filed later.

After a few slight adjustments to their southerly course, they get a radar "contact" about 3.5 miles away at their 4 o'clock, on a bearing of 280 degrees (back towards the coast), doing 230 knots (about 264mph). 


German pilot Oberleutnant Friedrich Fritz Sünnemann, 33, hails from the little medieval town of Aschersleben in Saxony-Anhalt. Over the past four years he has flown Junkers Ju 52 and Ju 86 aircraft, Heinkel He 111s and Dornier Do 17s.

He is now flying Do 217s with 5./KG-2, based at Soesterberg in The Netherlands. He and his three crew - observer Heinz Orchel, wireless operator Gerhard Duwe and gunner Heinz Oesterle - are part of a raid comprising six other KG-2 Do 217s and 33 Junkers Ju 88 bombers from KG-6 that are intending to hit the port of Grimsby in three waves.

But their Do 217E-4 aircraft, works number 4376, coded "U5 + BN", is now being stalked invisibly by Wills and Ledeboer.

Wills swings the RAF night fighter onto a south-westerly heading and closes gradually to about 1,000ft behind the Dornier, when he can see its silhouette against the clear, brightly moonlit sky.

At a range of 600ft, directly behind it, Wills thumbs the cannon firing button and the four 20mm Hispanos under the Beaufighter's nose send 118 rounds towards the Dornier.

The front of it explodes. Bits "flew off in all directions". Taking no evasive action, the enemy aircraft falls away to their starboard "in a mass of flames" and they see it hit the sea, debris burning on the water for some time.


My depiction of these events was commissioned by the son of Flying Officer Wills, who has his logbooks covering his first training flights at Moose Jaw in Canada in 1940, right through until he retired from flying in the RAF in the early 60's.

His entry for this night notes the enemy aircraft as, he thought, a Junkers Ju 188 – although the intelligence report says it was "thought to be a Heinkel He 177".

It is only with the benefit of post-war research, the assistance of a Luftwaffe and Allied air forces discussion forum, and various databases, that I was able to point to the only likely casualties of the night's events.

I was struck by the clinical precision with which the intercept was carried out on the RAF side. We expect this sort of technology-driven warfare these days; perhaps not so much in 1943.

But there is a horrible twist to this story that you might not have heard about. I hadn't.


Although Wills brought down one of the raiders, most got through – and inflicted terror on Grimsby that people still remember. As well as high-explosive and incendiary ordnance, the German aircraft were carrying so-called "butterfly bombs". 

These Sprengbombe Dickwandig 2kg, or SD2, were - in modern parlance - cluster sub-munitions. The aircraft dropped a casing that burst open to deploy 23 of the "bomblets": 76 mm (3 in) long iron cylinders that flipped out "wings" - hence the name. These spun in the airflow to arm a fuse. They had only 225g of explosive but could kill people within at least 10m (33ft) and maim over 10 times that area.

Even worse, their fuses were often delayed. So they were strewn around and looked like objects of curiosity – especially to youngsters. And there were several thousand of them all over Grimsby and Cleethorpes.

The result was that 14 people were killed during the raid – and some 47 over the next day.

I cannot say whether the Dornier that Wills and Ledeboer shot down was carrying these munitions. Are they what scattered in all directions so explosively when their cannon shells struck it?

Circumstantial evidence suggests that might have been the case and that the RAF airmen, with their airborne radar technology, prevented at least some of them being dropped on the port.


To buy prints of any of my works please visit

As well as commercial assignments I also do private commissions, for individual aircraft or bigger scenes.  To get in touch visit the Contact page on my website. Find Flight Artworks on Facebook, on Twitter @flightartworks, and on Instagram @flight.artworks.

Seeing the lights

P-Popsie at the Mohne sm
AJ-P attacking the Mohne Dam, 17 May 1943

High Wycombe, 1 Feb 2013

Seeing this picture in my Dambusters series several people queried - or challenged - the fact that I have the lights pointing off to the right of the aircraft.

So I thought it was worth explaining this. It does not help that a number of aviation artists have in the past got this wrong, typically showing the lights either pointing straight down or off at an impossible angle when the aircraft are banked so as to remain pointing down. Both wrong. 

If you have seen the celebrated Michael Anderson film made in the 1950s about The Dam BustersTM you will know that clever old Guy Gibson was not only a wonderful team leader, pilot and dog owner but also a part-time engineering genius who cracked the problem of how to fly a Lancaster bomber at a consistent 60ft over water at night when no altimeter was accurate enough to measure this. 

Visiting a London theatre our hero notices how the two spotlights illuminating the star of a dance number track her to and fro across the stage at a precise distance from the front. Eureka. 

This might not be complete tosh in that I think I read somewhere that some of the aircrew claimed they had remarked on just this phenomenon.


But the solution for 617 Squadron's special Lancaster bombers in reality is down to a man who must have been paying attention in geometry lessons at Manchester Grammar School: George Pickard, who in 1938 was posted to the Royal Aircraft EstablishmentFarnborough. He designed a simple altimeter using two spotlight beams to help Coastal Command aircraft fly low at night to attack submarines. The device was recalled by Ben (later Sir Benjamin) Lockspeiser at the Ministry of Aircraft Production and applied to the Lancasters.

There is a formula for positioning two Aldis lamps on a Type 464 (Provisioning) Lancaster along the lines of d1 = [(h1 + 1 in) x tan 30° -0.7in] feet ... and so on. 

The upshot is that you have one in the front camera housing under the aircraft's nose angled 30° to the right and another at the back of the bomb bay angled 40° to the right but also forwards, in such a way that their beams form two adjacent circles in a sort of figure-of-eight arrangement out under the starboard wing at 60ft below.

This can be monitored by the navigator (but certainly not the pilot or the bomb aimer, who are rather busy) who then call out, "Up a bit, down a bit ... ". When the aircraft is too high, the rear spotlight's pool of light moves forwards and when it is too low it moves back. 

There is a small general arrangement drawing on the RAF Museum website. I would direct you to a better, scaled diagram as well except that I think my own picture above gets it just right so far as I can tell. A two-page explanation with graphics can be found in, of all places, the Haynes manual for the Dambusters' Lanc. - part of that series of theirs which, worryingly, does also include the Star Wars freighter Millennium Falcon and the Star Trek flagship Enterprise.

I digress. Maybe not though. The other big challenge in this latest picture was: what do tracer bullets look like? I think I will save that for another time.