On the path of the RAF Musuem’s Dornier 17Z

Formation of Do17Z Bomber Aircraft in 1940 (wikipedia Commons)
Formation of Do17Z Bomber Aircraft in 1940 (wikipedia Commons)

If asked to name some famous aircraft from the Battle of Britain,  most people would think of Sptifires, Hurricanes, Messerschmits, Heinkels and Stukas  The announcement of the plans to raise   Dornier Do 17Z Werke nr. 1160 from the  bottom of the English Channel has thrown the spotlight on a duel between a pair of aircraft.  This duel touches on the controversy within the RAF about the best way to fight the battle of Britain. It also illustrates the link between the Battle of Britain and the night bombing of Germany.  Hidden in the landscape too are the places that tell this story.

The Dornier 17Z being recovered by the RAF Museum is the only example of its type in the world. This aircraft is also a particularly significant part of our battlefield heritage. It is not simply an example of a mediocre military aircraft from the mid 20th Century. This is a German bomber shot down by the RAF on 26th August during the Battle of Britain; a dramatic episode in our history, ranking alongside 1066, 1588 and 1805. This is on a par with say, a suit of armour worn by a French noble at Agincourt or by one of Richard III’s followers at Bosworth. The project needs support from donors and you can donate here https://support.rafmuseum.org/dornier-17-appeal

According to the information sheet written by Andrew Simpson and provided by the RAF Museum,

Dornier Werke nr. 1160 was 7/KG3 (7 Staffel (Squadron), III Gruppe of KG.3 with fuselage codes 5K+AR, which was based at St Trond in Belgium on 26th August 1940. This source says that this aircraft was part of a combined formation of Dorniers from KG2/3 despatched to bomb Debden and Hornchurch airfields. Seven aircraft of the 7 Staffel started to bomb an aerodrome, probably Debden, causing some damage.

No 264 Squadron Defiants in formation (Wikipedia Commons)
No 264 Squadron Defiants in formation (Wikipedia Commons)

Accounts of its loss vary from source to source; The original PoW Interrogation Report states that before reaching the target, when flying above clouds this aircraft seemingly became separated from the rest of the formation and lost its bearings. It was attacked by fighters, probably one of the RAF Hornchurch, Essex based Boulton Paul Defiants of No.264 Squadron RAF led by Flt Lt Banham, from their forward base at RAF Manston, Kent, which hit both engines and the cockpit as one,  of between one and six, as again published accounts vary – Dorniers brought down by the Defiants, who lost three of their number to defending Bf109s. At around 13.40 hours the aircraft force landed on Goodwin Sands off the eastern Kentish coast at low tide. Of the four crew, two (Wounded Pilot Feldwebel Willi Effmert, and Bomb Aimer Uffz Hermann Ritzel) became Prisoners-of-War in Canada and two (27-year old Wireless Operator Unteroffizier Helmut Reinhardt and 21-year old Bomb aimer Gefreiter Heinz Huhn) were killed, their bodies being recovered later and buried in Holland and the UK (Cannock Chase German cemetery) respectively.

Map showing the locations of the actions on 26th August 1940. (New Zealand Official History)
Map showing the locations of the actions on 26th August 1940. (New Zealand Official History)

This air battle has some important consequences for the Battle of Britain,and is part of a

Dornier17Z bomber formation with the coastline behind them. (wikipedia commons)
Dornier17Z bomber formation with the coastline behind them. (wikipedia commons)

controversy which has continued ever since. 26th August is roughly half way through the Battle of Britain, at the height of the Luftwaffe attacks on the RAF Fighter Command Airfields. On this day the Germans would lure the RAF forwards to fight in an air battle over Kent and then send in a bomber force to try to knock out Fighter Command Airfields at Debden and North Weald and North of the Thames in Essex. These airfields were beyond the range where the bombers could be escorted by the singe seat Me109 fighters.

No 11 Group RAF, under the command of Keith Park was responsible for defending London and the South East and bore the brunt of the Battle of Britain. Their squadrons were directed towards incoming raids using the sophisticated integrated air defence system developed under Hugh Dowding. Their own airfields would be defended by squadrons from the neighbouring No 12 Group under Trafford Leigh-Mallory. On 26th August this did not work. The cloudy conditions of the day helped the Germans to remain hidden from the RAF, and Debden airfield was bombed at 15.20 hrs killing several servicemen and causing damage. This was one of the incidents which triggered the conflict between Keith Park and Leigh Mallory, the respective commanders of No 11 and No 12 Groups, the debate over the “Big Wings”, and the side-lining of both Dowding, the Commander of Fighter Command  and Park. This is a controversial episode in the story of the RAF which still makes ripples today, and is a fascinating case study of leadership and management which still offers lessons.

The RAF Museum information sheet leaves some questions about the relationship between Dornier Do 17Z Werke nr. 1160 and the raid on Debden. This aircraft appears to have crash landed two hours before the raid on Debden took place and may have been the result of some other engagement. According to the RAF Official History,(1) there were two major day raids on Monday 26th August 1940, not one raid as is the impression given by the information sheet. The first raids took place between 11.35-13.40 and took the form of a series of air raids on towns and airfields in Kent. The raiders included aircraft from III/KG3, and were intercepted by aircraft from, five squadrons including 264 Squadron. 264 Squadron, equipped with Defiant fighters and No 56 Squadron with Hurricanes sighted a formation of twelve Do17s near Deal before noon. The German bombers were flying at 13,000 ft and protected by thirty to fifty Me109s. The seven Defiants succeeded in getting at the bombers and claimed to have shot down six of them. However, the Me109s harassed them continuously shooting down three Defiants. This is the action which appears to fit the circumstances of the loss of the Dornier of No 7 Staffel of III/KG3 as it took place close to the Godwin Sands, a gliding distance from East Kent. The timings don’t quite fit either, but might make sense if the time of the crash was reported by the Germans using French/German time an hour ahead of the local UK time.

The loss of this Dornier to a Boulton and Paul Defiant has a certain historical irony. The connection between these aircraft is an interesting case study in the development of military technology.

The Boulton and Paul Defiant from "Britain's Wonderful Fighting Forces" (1941)
The Boulton and Paul Defiant from “Britain’s Wonderful Fighting Forces” (1941)

The  1930s was a period of technological change in military aviation. New engine designs and the potential of aluminium stressed skinned air-frames offered the potential to fly much faster than possible with fabric and braced struts and stronger structures than could be destroyed by the twin machine guns of contemporary fighter aircraft. The Dornier 17 was specified in 1932 as a “mail carrying aeroplane” but intended for reconnaissance. The resulting aircraft was faster than most biplane fighters and won an speed award in a 1937 air show in Switzerland, its top speed of 255mph was faster than French or Czech fighters. But by 1940 Do 17Z Werke nr. 1160 was already obsolescent. Fighter design had caught up and the Do 17 was slower than the RAF single seat fighters. Its bomb load was much smaller than the Ju88 and He 111 and new versions of the aircraft had already been commissioned. Although KG3 continued to fly this type of aircraft through the Blitz of 1940-41, from May 1941 the Wing converted to the Ju88. III/KG3 was the last to convert, in the following winter returning from the east front to Guetersloh in Germany.

The Bolton and Paul Defiant is often ignored completely in popular accounts of the Battle of Britain, and when mentioned it is usually as an example of a failed aircraft design. Any internet search of “ten worst aircraft of WW2” will find the Defiant high on the list. Yet the idea behind the aircraft had a lot of merit.

The power operated Fraser Nash Turret in this No 264 Squadron Defiant contained a battery of four .303 browning machine guns, each with 600 rounds of ammunition.(wikipedia Commons)
The power operated Fraser Nash Turret in this No 264 Squadron Defiant contained a battery of four .303 browning machine guns, each with 600 rounds of ammunition.(wikipedia Commons)

No one knew how aerial warfare might be possible with the 1930-40s generation of aircraft. The aircraft of the Great War flew at the same sorts of speeds achievable by a fast sports car, and needed to close to within 50m to achieve a kill. Twenty years later aircraft could fly two to three times faster, raising questions about whether aerial combat would possible at all.   In the 1930s the major threat as perceived by the RAF was of German bombers attacking Britain from Germany. The thinking of the time envisaged aerial bombardment by explosive and chemical weapons which might cause thousands of casualties. This was the era when it was believed that the bomber would always get through. To its credit the British Government and the RAF invested in developing technology to defeat bombers, which paid dividends in 1940. One of the major problems was overcoming the difficulty of deflection shooting with the high speeds of WW2 era aircraft. One solution was to develop a large battery of guns in the wings of a single seat fighter, as adopted with the Hurricane and the Spitfire.

Another solution was for the fighter to fly a parallel course and eliminate the need for deflection shooting. The Boulton and Paul Defiant, like the Hurricane and Spitfire was a monoplane fighter powered by a Rolls Royce Merlin engine. However, the Defiant had a crew of two with a gunner in a Fraser Nash power operated turret to provide a battery of four 303 calibre machine guns which could shoot down a bomber by engaging it from any angle, ideally from some blind spot where the bombers could not engage. The RAF hedged their bets in defensive technology. Alone of all combatants in 1939, it had developed aircraft like the Defiant and the similar Blackburn Roc to use this method of fighting, as well as single seat fighters like the Spitfire and Hurricane.

One of the assumptions made at the time the Defiant was specified was that a German attack would be launched from Germany, outside the range of any single seat fighters. No one predicted that France would fall and the air attack would be from France and within range of single seat fighter escorts, which would find the slow and heavy Defiant easy prey. Although the Defiant could spring a nasty surprise on a German fighter which misidentified it as a Hurricane, the limitations and vulnerability of their aircraft had been identified before the Battle of Britain started. 264 Squadron had taken heavy losses in May over Dunkirk and had been withdrawn to the Midlands beyond the range of German single seat fighters. The fact that this squadron was in the air over Deal on 26th August 1940 shows the limits to which Fighter Command had been stretched.

The Bravest of the Few? A group of aircrew from No 264 Sqn, the unit with the highest aircrew mortality in Fighter Command during the Battle of Britain. (wikipedia Commons)
The Bravest of the Few? A group of aircrew from No 264 Sqn, the unit with the highest aircrew mortality in Fighter Command during the Battle of Britain. (wikipedia Commons)

This air battle on 26th August is one of the few occasions where the Defiants were used against a bomber formation.  According to the 264 Squadron records the Squadron shot down seven Do17s for the loss of three Defiants.

The Commonwealth War Grave Commission records show that on that day two sergeants from 264 Squadron died. 26th August was a relatively good day for the Defiants as a total of fourteen men died between 24-28th August 1940, just under half the number of aircrew established for the Squadron, and more than lost by single seat fighter unit in the battle. One of the advantages the RAF had over the Germans in the Battle of Britain was that many RAF aircrew could bail out of a stricken aircraft and return to the fight, while any Germans shot down would be a prisoner of war.  The RAF reported 324 single seat fighter lost in August for the loss of 126 of the pilots killed. Just under two thirds of the pilots parachuted to safety.  That isn’t the case with the Defiants of 264 Squadron who appear to have lost two aircrew for each aircraft.  There are enough first hand accounts of the experiences of “The Few”, to know of the fearful experience of being attacked by a German fighter with only the armoured seat for protection and then bailing out from a crippled and burning machine falling from the sky. How much harder was it for a Defiant gunner, unprotected by armour to survive an attack, or to bail out of a Fraser Nash Turret if the power failed or the mechanism was damaged by cannon splinters?  RAF losses for August. I wonder too, whether the presence of a crewman inhibited Defiant pilots from jumping rather than stay with their  stricken machine to try to maintain control for as long as possible?

Two days after the action on 26th August, 264 Squadron were withdrawn from No 11 Group to No 12 Group and were tasked with operating as night fighters. The although the Defiant was heavier and less manoeuvrable aircraft to fly than either the Spitfire and had a landing speed over 100mph, it was a stable aircraft which made it more suitable as a night fighter. In Autumn 1940 the RAF had no means of finding the enemy other than the Mk1 eyeball and 264 Sqn struggled in this role through the Blitz. In 1941 they received Mk II Defiants which included a Mk VI Airborne interception radar operated by the pilot This seems less efficient than an arrangement allowing the pilot to concentrate on flying the aircraft and keeping visual look out while a second person on board operated the radar, as in the Beaufighter and Mosquito night-fighters. 264 Sqadron soldiered on with the Defiant until 1942 when the Squadron was converted to the Mosquito, a much better night fighter and the air gunners were posted out and replaced by navigator radar operators.

This isn’t quite the end of the story. In the mean time the Germans had found themselves

Prey Turned Hunter. Dornier 17Z fitted with SN2 airborne Interception radar. Lieutenant Ludwig Becker used an aircraft like this fitted with the prototype of this radar to shoot down five bombers in August 1941.
Prey Turned Hunter. Dornier 17Z fitted with SN2 airborne Interception radar. Lieutenant Ludwig Becker used an aircraft like this fitted with the prototype of this radar to shoot down five bombers in August 1941.

considering the defence of the Reich from nocturnal air attacks. An interest sharpened by the raid on Berlin on the night of 25-26th August and whose raiders would be tucking into their breakfast about the same time that 7./KG3 would be waking up to theirs. Night air defence was low on Luftwaffe priorities and the night fighter force used the aircraft they could. Given that the Do 17 was becoming obsolete as a day bomber, the German night fighter force started using the Dornier as the basis for a night fighter. It had a sufficient margin of speed over the RAF’s Hampden,Wellington and Whitley bombers. Replacing the perspex nose with a fairing with a 20mm cannon and three machine guns and, or a gun pack under the nose gave the Do 17 as much fire-power as a day fighter. On 2nd October 1940 a Do17Z of NJG 1 (Night Fighter Wing 1) command by Lt Ludwig Becker made the first successful German radar controlled interception on 2nd October 1940, shooting down a Wellington Bomber.  The Germans too were developing airborne radar, and in August 1941 the same Lt Becker using the prototype Lichtenstein BC (FuG 202) airborne interception radar shot down five British bombers. Over the next two and a half years the Do17 and its redeveloped versions the Do 215 and Do217 were one of the mainstays of the German night fighter force, until replaced by better machines, such as the Ju88 R1, a faster machine.

Junkers_Ju_88_RAF_Hendon
This Ju88 R1 was flown to England by a defecting crew, on 9th May 1943 bringing with it the secrets of the SN 2 (Fu202) airborne Interception radar.

The RAF Museums JU88R-1 W/Nr 360043, served with IV/NJG.3, coded D5 + EV is anachronistically  displayed in the Battle of Britain Hall, as it is part of the story of the air offensive on Germany told alongside the RAF Bombers it once stalked in the Bomber Hall.  While this aircraft is a version of the Ju88 which flew in the Battle of Britain, it is the sleek fighter version without the bulbous crew crew compartment or the glazed “beetle Eye” nose of the bomber version, and antennae sprout from its nose.   This is also a very special aircraft with a provenance which gives the same significance as, say a machine flown on the dams Raid. This is an aeroplane which made an individual difference to the war, and saved many allied lives. The Ju88 R1 is not the bomber version which flew over Britain in 1940. but a night fighter variant with a sleek shallower fuselage and a crew of three rather than four, equipped with a battery of 20mm cannon, an average of ten shells from which would destroy a heavy bomber like a Lancaster or Halifax. Most important this version has a fairing covered in radar aerials of the production version tested by Lt Becker.  This particular aircraft was obtained by the RAF when a Luftwaffe night-fighter crew defected to England, on 9th May 1943 bringing with it the secrets of the Lichtenstein SN2 airborne interception radar, enabling the British to develop counter-measures. 

The Germans too thought about the problems of deflection shooting at night. British heavy bombers like the Wellington, Sterling Halifax and Lancaster all had a power operated Fraser

Diagram showing the installation of two 20mm cannons to fire obliquely above the cockpit of an Me110G2. The Me110 G2 anachronistically displayed in the RAF Museum Battle of Britain Hall is fitted with this Schräge Musik "Jazz Music" for shooting down RAF night bombers.
Diagram showing the installation of two 20mm cannons to fire obliquely above the cockpit of an Me110G2. The Me110 G2 anachronistically displayed in the RAF Museum Battle of Britain Hall is fitted with this Schräge Musik “Jazz Music” for shooting down RAF night bombers.

Nash rear turret mounting four machine guns, and manned by a gunner whose warning could initiate evasive manoeuvres which could throw off an attacker. Some Germans thought about the idea of oblique fire, approaching a bomber from underneath. Ober Leutentant Schoenert, a 23 kill “experten” from from NJG 1 had a Do 217 modified to include two upward pointing 20mm cannons. With this machine he achieved the first German kill using this technique in May 1943. The technique was widely adopted by the German night fighter force. So the technique which the RAF dropped, was adopted by the Luftwaffe and became a great success under different operational circumstances. Thus the Do17 became the hunter rather than the prey. 264 Sqn’s Air gunners left the squadron in mid 1942. I do not know what happened to them, but it would be an unfortunate irony if the RAF had posted these experienced air gunners as rear gunners in the Bomber squadrons,

There is a lot to see relating to the events of the Battle of Britain and the battle on 26th August. Of course the RAF museum has a lot of the aircraft involved, including the only surviving Bolton and Paul Defiant and at some point in the future, Dornier 17z. Here are some other places associated with the stories in the battle:-This could be the focus for people with an interest in wider aviation heritage.

  • Bentley Priory Museum (Currently being redeveloped) where the information from different sources was filtered and passed to Groups as plots of raids.
  • No 11 Group Command Bunker Uxbridge, where the Group Controller made the decision to commit No 264 and 56 Sqns to intercept 7./KG3.
  • RAF Northolt Restored Sector Control Room, the only No 11 Group Control Room in existance.
  • The reconstructed Sector Control room at the Imperial War Museum Duxford IMW, is where the No 12 Group aircraft were scrambled to intercept the raiders at Debden – but arrived too late.
  • The underground control room at Dover Castle, where the AA defences on that day were controlled.
  • RAF Debden, the target for the raids in the afternoon is a very well preserved Battle of Britain airfield, but is now Carver Barracks and home to No 33 Regiment Royal Engineers.
  • RAF Manston, the airfield where 264 Sqn used as a forward base on 26th August 1940 is now Kent International Airport, and there an RAF Manston History museum next to the Spitfire and Hurricane museum at Kent International Airport.
  • RAF Hornchurch, where 264 Squadron were based for their costly week in No 11 Group is now Hornchurch Country park. Most of the administration and technical areas of the airfield are now a housing estate. It was the subject of a Tv archaeology programme in the “Two men in a Trench” series. Some buildings have been preserved, includign the Offciers Mess, now a medical centre. The local pub, the Good Intent, which served airmen from the base has in recent times had a collection of photographs.
  • St Trond Airfield became a Belgian Airforce Base after the Second World War. It is now Limburg Regional Airport.
  • Gefreiter Heinz Huhn is buried in Cannock Chase German Military Cemetery alongside about 5,000 other German and Austrian war dead from the World Wars.
  • The names of the eight of the fourteen men killed flying for No 264 Squadron whose bodies have never been recovered are commemorated on the Runnymede Memorial for the missing, overlooking London. A fitting place to remember and reflect.

Contact Air Power tours if you would like to find out more about visiting the sites associated with this air battle.