Messerschmitt Bf 110 vol. I

Messerschmitt Bf 110 vol. I

Even if they failed to contact the enemy, every one of their sorties amounted to a brush with death. There were many dangers for Luftwaffe night fighters to contend with;

hazardous weather conditions, fog rolling out of nowhere, machine-gun fire from the British bombers, enemy night fighters at work over German airfields and simple fatigue could all lead to tragedy. One of the men who survived all of this was Ofw. Kurt Bundrock. Born on 2 February 1917 in Berlin, Bundrock flew as Bordfunker (radio operator) with NJG 1 ace Hptm. Reinhold Knacke (44 night victories). He recalled his experiences:
“..I’d be more than happy to tell you what a typical “Dunkle Nachtjagd” mission looked like before we had on-board radar. We were guided by ground radar over the radio to the general area of the enemy and given information about his altitude and heading. At that point we had to depend solely on our eyes and were at the mercy of visibility and the whims of the enemy pilot. There were times when the first thing we saw were his exhaust flames, while the enormous silhouette of the plane was all but invisible.
“Our exhausts were shielded by long flame dampers and were visible only from a position directly behind us. The English, even with flame shields, emitted flames that could on occasion be visible from 100-150 meters.
Turbulence was a good sign that the enemy was near. When our machine began to shake and lurch, we knew that we were behind him and the pilot would release the gun safety and keep his thumb on the trigger, ready to unleash a salvo from our four machine guns and two cannon at any moment.
“There he is! Three o’clock, three hundred meters!”
Initially we noticed a slight silhouette in the night sky, and then, as we moved in, a more defined outline. Knacke flew his closing approach, keeping some 50 meters below the English plane because it was easier to make out the outline against the sky than the horizon, where it blended in.
The bomber flew in a rocking motion and because of this we were unable to make out the type. At the same time we knew we had to watch out for a tail gunner, a dorsal gunner or both. Once we were certain, we could decide on the appropriate tactics.
In the meantime the pilot’s voice came over the headset – «Short Stirling, Pauke, Pauke!»  And ground control would reply – «Viktor, good luck!»  Knacke began climbing and positioned himself underneath and to the side of the huge machine. The difference in size between the two planes was like that between a small sports car and a tractor-trailer. When we were 50 meters from the Stirling we started to follow his maneuvers and closed in to 30 meters.

Messerschmitt Bf 110D-3 of 7./NJG 1 during flight over North Sea, “Englandblitz” unit emblem under the cockpit. [Kageros's Archive]

“I hope his bombs don’t go off when you hit him, sir,” I said through the throat-mike. Knacke replied calmly, “I’m going to go for the left wing.” That was reassuring because if the bomber exploded it would take us with it.
The Leutnant lifted the nose so fast that it seemed as if something was pushing our tail down. At the same time a long burst ripped from our machine guns and tore into the left wing between the fuselage and engine where the fuel tanks were. We had gotten dangerously close and Knacke allowed the plane to drop to the right and brought us out of the dive after we had gotten a safe distance from the Stirling.
We saw some embers and sparks and a trail of lightly colored smoke, but there were no flames. The Stirling started to dive to evade us, but we followed it down. At the same time the tail gunner opened up on us and the bomb bay doors opened as the pilot jettisoned his bomb load.
From a slightly higher altitude Knacke loosed off bursts at the right wing, allowing the bullets to tear into the fuselage. The tail gunner was constantly correcting his aim, and when we fired he could see us better. We had the advantage of speed though, and we quickly veered from his starboard to port side and went below his line of sight. The Stirling began to burn, and pieces started to come off, swept along by the slipstream. We circled around at a constant altitude and watched as the bomber plunged earthwards. At the point of impact there was an enormous explosion.
I made a note of the time, wrote a detailed report of the conditions and based on information from ground control I made an estimate as to the wreck’s location. Ground control asked if we had seen any parachutes. We replied in the negative.
But it wasn’t always that easy. On average a night fighter had to mount two or three attacks. Often during the second or third attack we would take hits ourselves, which made us stand out from the other crews. Knacke was young, (b. 1919) very courageous but not crazy or foolhardy. In spite of that, he tended to get too close to the enemy. I think he was afraid that he would miss, since I noticed more than once that he wasn’t a very good shot and he had trouble aiming at a moving target.
I remember one such occasion when ground control at Würzburg-Riese on Sylt island guided us over the North Sea between Sylt and Heli­goland onto a twin engine Whitley bomber. Knacke made his first attack from below and from the side. The only effect was a few defensive maneuvers and a series of tracers from the tail gunner.

Messerschmitt Bf 110C-1, KD+TM in RLM 70/71/65 camouflage. On the photo from German publication the aircraft has retouched fuselage code. [Kageros's Archive]

During the entire dogfight I kept the transmitter button depressed so that ground control could follow what was going on, allowing them to listen in on the conversation between Knacke and myself. Throughout I kept thinking that it would be good if ground control kept track of the situation. This way they would be able to send a search team to fish us out of the cold waters as soon as possible.
We made our second attack from slightly below and directly behind the enemy. It was unsuccessful.
We couldn’t get in close enough due to the defensive fire.
During the third attack we closed from the rear to take out the gunner from a distance of about 80 meters. The Whitley banked into a turn that usually only a fighter plane would make and we knew that a first rate pilot must be flying her. We heard bullets slamming into our kite during the firefight. We made our fourth pass as the Whitley was doing wild aerobatics and a few shots hit her in the belly which caused some ripping but no flames were visible. During the fifth pass we didn’t even get one shot off, but something tore into our “cardboard box,” as we called our planes at the time. We had been conducting these maneuvers at between 1,500 and 2,000 meters. We made our sixth attack, again from behind and from below with the tail gunner still shooting at us. The British pilot decided to try and escape by diving down to wave-top height. This would prevent us from attacking from below and force us to attack from within range of his tail gunner. Our faster plane didn’t help either, since the larger crate was surprisingly agile. The sixth attack failed to produce any visible damage, but the Whitley’s evasive maneuvers had slowed it down. One of our rounds must have hit them in the fuselage. We dove in from above for the seventh attack under heavy fire. Again the bomber’s fire rattled against our Messerschmitt and one of our engines began to cough.
The Englishman began climbing and turned hard on his right wing and almost lost control, but he regained it a moment later and we noticed white smoke coming out of the starboard engine.
Knacke remained quiet and with the port engine starting to splutter, made a wide turn to follow the Whitley. The bomber was to our right and was trailing a medium length banner of white smoke. Knacke turned to follow and the Whitley slowly came into range. The next salvo tore into the area between the fuselage and left engine. The plane flew on like a lethally wounded animal without making any evasive maneuvers. Then we saw a second smoke trail from the right side of the aircraft. The gunners were silent and we had no idea whether they were dead or out of ammunition. The plane plowed on.
During the ninth and last attack there was no defensive reaction of any kind and Knacke hit the left wing with short burst which set off a flash of bright flames. After a short dive the bomber exploded in a bright cloud of fire. We watched as a cloud of light smoke billowed up from the spot where the bomber had impacted the water. The brave crew went down into the depths of the North Sea.
Knacke slowly changed course and headed for Sylt. While still in the turn he had to shut off our port engine, which was coughing and spewing out white smoke. “We’re losing altitude,” he said. “How much farther to Sylt?” he asked. I replied, “I think about 80 or 100 kilometers, I’ll let you know more precisely in a moment.” I asked ground control for our exact position, since they had been monitoring us the whole time and requested that they notify the naval rescue teams in the area. The officer in charge of fighters told me that a rescue boat was in the vicinity, the airfield was being lit and fire fighters were on standby.

Survey of Daimler-Benz DB 601A engine on ­Messerschmitt Bf 110C-4. Note tip of airscrew spinner in squadron color.[Kageros's Archive]

That’s when Knacke told me that we were losing power in the starboard engine. Up until that time, I had never considered the possibility that we wouldn’t make it back to our airfield. We had flown on one engine before without problems, but what would happen now that the second engine was losing power? What would we do if it seized?
Our position was awful. The starboard engine was still losing power and was starting to splutter. We were slowly, but systematically losing altitude. We could still jump as long as we were above 850 meters and in addition to our life jackets there was a two-man inflatable life raft behind my seat.
Finally the airfield came into sight and we could make out the runway lights at Westerland. “Maybe we’ll be able to make it,” I said hopefully. “We have to be prepared for the worst,” Knacke replied softly. We were still about 500 meters above the ground and our airspeed was bleeding off perceptibly. The situation was serious.
“I’ll try and start the port engine to give a little bit more power and altitude,” stated Knacke as he pressed the starter. The engine coughed, spit out a few flames and gave up in a shudder that vibrated the whole plane. It had given up the ghost.

Altitude: 300 meters. We were slowly approaching the airfield and we could now see the clear outline of the runway. “If we can make it to the runway, I can belly in..” said Knacke, and added a moment later, “Bundrock, take a look at this, but move slowly!”
I slowly leaned forward and watched as Knacke moved the stick around as though stirring coffee in a cup. “For God’s sake, what are you doing?” I cried out. “The stick doesn’t work at all. I’m flying with just the elevators and landing flaps,” he replied calmly. At that moment he really impressed me. We had actually made it back to the airfield on one stalling engine. In expectation of the rough landing, I got free of the parachute and stored it between the radio cases and just as we touched down I pulled on the emergency canopy release.
At that moment there was a loud bang, the noise of our impact, grinding and flying dirt until the plane finally came to a stop. An unpleasant hissing finally broke the incredible silence that followed. Knacke shouted “Run!”
I noticed that the starboard engine was on fire and the flames were getting bigger and brighter and people were running towards us. Cars and fire trucks were speeding in our direction. Knacke jumped out and over the nose, while I headed for the tail and we both ran as fast as we could to get away from the burning plane. It could have exploded at any minute.
It didn’t blow up, though, since the firefighters were able to get a layer of foam onto it in the nick of time. With our heads down, we set out on the long walk back to the mess hall. Neither of us said a word.

Early Development
During WWI the German military used a number of frontline “multi-purpose” warplanes, the most notable of which was probably the Hannover CL II. They were two-seaters designed for escort and reconnaissance roles in the Schutzstaffeln (air cover/escort) squadrons. It became obvious during combat missions that the planes also performed well in an attack role and in March 1918 all thirty-eight Schutzstaffeln squadrons were converted to Schlachtstaffeln (attack) squadrons. These aircraft had the lowest loss rates of all two-seat planes used in Germany.
Impetus for re-newed development of this type of warplane (Kampfflugzeug) came in the early thirties during the planning for the new Luftwaffe. The Rüstungsflugzeug II (tactical bomber) was to be a single engine, two seat multi-purpose aircraft which could be used in the fighter, reconnaissance or light bomber roles. After Adolf Hitler came to power on 30 January 1933, the planning to create a new German air force forged ahead. On 27 April 1933 the Reichsluftfahrtministerium (RLM, or Reich Aviation Ministry) was created and WWI flying ace Hermann Göring appointed as Oberbefehlshaber or supreme commander.
Another former WWI fighter pilot and member of the board of directors at Lufthansa, Erhard Milch, was appointed Secretary of State in the new ministry. Milch was put in charge of C-Amt (section C) overseeing the technical development of combat aircraft.
In early 1934 the Luftwaffe released a study of the most probable developments in aerial combat tactics introducing a new concept for a twin engine, multi-seat strategic fighter embodying long range and a heavy armament of fixed and traverse-mounted cannon instead of bombs. The cannon were to cover the airspace ahead of and behind the aircraft with some limited coverage to the sides. According to the study, this “strategic fighter” was to operate ahead of the bomber formation to secure the airspace and ensure a safe route to the target area and could also be employed on both reconnaissance and bombing missions. The concept was questioned not only by those officers in the Luftwaffe who felt that such deep penetration tactics would lead to high losses, but also by aeronautics engineers who claimed that the planes would be heavier, slower and less maneuverable than the bombers that they were meant to defend. In spite of the objections, this so-called Zerstörer (destroyer) class of aircraft was much liked by Hermann Göring, who ordered work be started on designs for construction.
Shortly thereafter two guests from the Bayerische Flugzeugwerke showed up at the Reich Aviation Ministry. One was Willi Messerschmitt, the owner, the other Robert Lusser who was the head of the design department. Together they presented their concept for a new airplane, designated Projektnummer 1035. It was to be a destroyer class aircraft, which could also perform the roles of high-altitude reconnaissance plane or bomber. Each version had a slightly different fuselage.
In June, 1934 the RLM announced the specifications for the Kampfzerstörer (bomber/destroyer) through its technical development department which sent invitations to bid to AGO, Bayerische Flugzeugwerke, Dornier, Focke-Wulf, Heinkel and Henschel. The three or four-seat plane was to be powered by two Junkers Jumo 210 engines to achieve a cruising speed of 330 km/h at 6000 meters and a top speed of 400 km/h at that altitude. Armament was to consist of two forward-firing 20 mm cannon and a twin 7.92 mm machine gun installation. The minimum range was set at 2000 km and the maximum service ceiling at 10,000 meters. The aircraft was to reach 6,000 meters within 15 minutes. Variants were to be submitted for high-altitude reconnaissance duties and both versions were to be capable of operating at night. The design should have docile handling qualities and be easy to bring out of a corkscrew, while being capable of pulling into sharp turns without falling off a wing.

One month later in July 1934, the RLM reviewed the propositions that had been received. Neither Dornier nor Heinkel had sent a proposition and offers from AGO and Gotha were rejected after a preliminary grading. AGO proposed the Ao 225, a twin-engine, low-wing monoplane design armed with four 20 mm cannon. Gotha’s proposition was for an unconventional plane called Projekt 3001/3002. It was an all-metal high-wing monoplane with twin tail booms. Two Daimler-Benz 600 engines were located in the fuselage while the propellers were located in the forward part of the tail booms and connected to the engines by a complicated system of gears. Armament consisted of four 20 mm cannon (two mounted statically in the nose and two in a canopy near the rear of the fuselage).

Interior of Messerschmit’s Bf 110D-3 cockpit, FuG 10 radio inside.[Kageros's Archive]

Orders were placed with Bayerische Flugzeugwerke (BFW), Focke-Wulf (Fw) and Henschel (Hs) to continue development on their destroyer/bomber ideas, which later became the Messerschmitt Bf 110, Focke-Wulf Fw 57 and Henschel Hs 124. Each company was to build three prototypes and five pre-production series aircraft, all to be powered by the Jumo 210. Wooden models were to be ready by February 1935 and the first prototypes constructed by February 1936.
After representatives from the RLM inspected the wooden mock ups in February 1935, they were more inclined to re-evaluate the Kampfzerstörer concept. The original concept to combine a fighter and bomber into one airframe turned out to be impractical. As a result, the RLM developed a new concept for a Schnellbomber (fast bomber). The new aircraft would need to reach a cruising speed of 450 km/h and a top speed of 500 km/h with a 500 kg bomb load. Armament was limited to a single 7.92 mm machine gun. These new requirements were sent to Junkers, Messerschmitt, Henschel and Focke-Wulf. The prototypes which they had been working on (Bf 110, Fw 57 and Hs 124) would become typical destroyer (Zerstörer) aircraft.
The authors of many post-war monographs devoted to the Messerschmitt Bf 110 have claimed that Willi Messerschmitt ignored the requirements of the RLM for the Kampfzerstörer type and that he had been working from the very beginning on a twin-engine strategic fighter plane. He had indeed omitted the internal bomb-load requirement, which worked to the company’s advantage when the Kampfzerstörer specification was amended. But an analysis of RLM documents fails to support the theory that this move was sanctioned because of Messerschmitt’s political connections. The Bayerische Flugzeugwerke was completely dependent on government contracts and Willi Messerschmitt had already incurred the personal enmity of Erhard Milch who personally made decisions about who was awarded government contracts. In fact, the differing approaches to the requirements set out by the C-Amt suggest that the RLM encouraged the three designs submitted (Bf 110, Fw 57 and Hs 124) to differ significantly in meeting the requirements. Milch thus gave himself more room for maneuver when making a decision as to which type best suited tactical and operational requirements.
On 1 November 1935 a two-year production plan was unveiled which included three prototypes and five production models each for the Bf 110, Fw 57 and Hs 124. The Bf 110 and Hs 124 were to be fitted with the Jumo 210, while the Fw 57V1 would get the Rolls-Royce Buzzard, and the Fw 57V2, Fw 57V3 and the Bf 110 V3 wold be fitted with in-line DB 600 engines. In this same document, even before the first prototype had flown, there were no orders for a series model of the Fw 57!
The fact that the experts at the RLM had doubts about the abilities of the plane at such an early stage in its development was not surprising. Suffice it to say that the type was supposed to have a wing span of 25 meters, 7 meters more than the Dornier Do 17 and 2 meters greater than the Heinkel He 111 while its weight was equal to that of the He 111 with a full bomb load! Given its size and weight there was little chance it would be capable of hunting down an enemy single-engine fighter.
During construction of the first Fw 57 prototype the designers moved away from British engines in favor of the Daimler-Benz DB 600. The plane made its first flight in the summer of 1936 with test pilot Kurt Tank. During one of the later flights the landing gear failed to deploy and the plane was damaged while landing on soft terrain. Hans Sandler, who piloted the plane in 1937 claimed that it was a heavy and clumsy machine that was unpleasant to fly. Because the Fw 57 program proved a failure, it is not known whether the V2 or V3 prototypes were ever finished.

The first prototype of the Henschel Hs 124V1 was flown in June, 1936. Its designer, eng. Nicolaus had conceived an all-metal, cantilevered mid-wing design with the landing gear housed in extensions of the engine nacelles. Only the moving parts of the control surfaces were canvas covered. It was powered by two Jumo 210C engines. A gunner’s station mounted in the nose added a lot of weight. The second prototype, the Hs 124V2 with BMW 132Dc radial engines was test flown in April 1937. The nose gun position was replaced with a plexiglas nose cone, typical of bombers and reconnaissance types. The third prototype, the Hs 123V3 was given Jumo 210C in-line engines, a new all-metal nose with a battery of guns comprising two 20 mm cannon and two 7.92 mm machine guns. There is no convincing evidence that the plane was ever flown. Its performance was, like that of the Fw 57, inadequate and as a result the Messerschmitt Bf 110 became the Luftwaffe’s primary destroyer type.

Prototypes and first production versions
In January 1936 the DVL/Experimental Aerody-namics Institute conducted wind tunnel tests on a Bf 109-type design with two wing-mounted engines, a precursor to the Bf 110. On May 12, 1936 Dr. Hermann Wurster made the first test flight of the Messerschmitt Bf 110V1 (WNr. 868). The plane had a slender, elliptical fuselage that thinned near the top. Structurally it was built in similar fashion to the single-engine Bf 109; two monocoque halves joined by flush threads. The skin was attached by inward bent edges that became formers when attached to the neighboring pieces. The monocoque construction was heavier than traditional semi-monocoque but significantly simplified mass production by allowing the mounting of internal parts and equipment before the two halves were assembled.

 Messerschmitt Bf 110E-2, WNr. 4495, CD+MO, produced by MIAG plant, during tests at plant airfield; Messerschmitt Me 210 in the background. [Kageros's Archive]

Fixed guns were mounted in the nose. Aft of these was located the fully glazed cockpit cabin with the pilot and crew in tandem. Behind the pilot, radio and navigation equipment could be operated from a small seat. Further aft was located the gunner’s station. Aft of the cabin were oxygen bottles and in the rear of the fuselage was a set of gyro-magnetic compasses. A retractable tail wheel was mounted on a fork attached to a VDM type strut with a spring shock absorber and a 350x135 mm tire.
The wings were semi-monocoque, single-spar, all-duralumin, trapezoid in shape with leading edge slats, slightly rounded edges and slight dihedral. Technologically the wings were related to those of the Bf 109. The single spar passed through the fuselage and was attached to its main steel beam as well as to two support beams. The engine nacelles were attached to the wings and housed the main landing gear as well as the engine oil tanks. The main landing gear was hydraulically controlled and when in the stowed position the wheels protruded slightly from the nacelles. The main wheels were attached to oleo struts with axles pointing towards the wingtips, with pneumatic drum brakes. 815x320 mm tires were used. The fuel tanks were mounted between the fuselage and the engine nacelles.
The tail control surfaces were all-duralumin, single spar semi-monocoque construction with double tail fins which gave the rear gunner a better field of view.
The aircraft was powered by two in-line, liquid-cooled, Junkers Jumo 210B engines with a displacement of 19.7 liters and a take-off rating of 600 hp each (max. 5 min.). Thanks to a supercharger the engine was able to attain top performance at 2,700 meters where it had a top rating of 640 hp (max. 5 min.), 575 hp (max. 30 min.) and 510 hp (continuous). Propellers were the two-blade self-adjusting Hamilton Standard type.
Compared to later prototypes, the V1 had a bulkier nose, flatter canopy for the rear gunner and more angular tail fins. The Bf 110V1 was mainly a test-bed for the engines and for testing the design in flight. The airplane was unarmed and its handling in flight was good with some difficulties during low speed flight. The biggest drawback were the weak engines which were unable to push the plane past 450 km/h. In October 1937 the plane was assigned the code D-AHOA and handed over to Erprobungsstelle Travemünde.
On October 24 1936 the Messerschmitt Bf 110V2 (WNr. 869, D-AQYE) was flown for the first time. It had elliptical tail fins. At first it was tested at the airfield at Augsburg and later at the test center at Rechlin.
In Lieferplan Nr. 4 (order delivery plan no. 4) submitted on 1 November 1936 for the period up to March 8, 1938 the RLM ordered a total of 104 series Messerschmitt Bf 110V2.
On December 24, 1936 Dr. Hermann Wurster made the first flight in the Messerschmitt Bf 110V3 (WNr. 870, D-ATII) fitted with carburetor fed 12-cylinder, liquid-cooled, in-line Daimler-Benz DB 600 engines with 33.9 liters displacement, producing a maximum 1,000 hp for 5 minutes, 900 hp for 30 minutes and 800 hp continuously. The engines powered three-blade VDM type propellers. Unlike later models initial Versuchs models had large radiator baths mounted under the engine nacelles and the oil coolers mounted under the wings. It reached 480 km/h at ground level and 505 km/h at 3,000 m.
Further tests were conducted using airframes of the pre-production Bf 110A-0 series. By July 1936, the RLM had ordered 9 such airplanes of which the first 7 were A-0 and the last two B‑0. Powered by Jumo 210B’s, the aircraft were not fitted with armament and the nose profile had been re-designed from the first prototypes. Test flights were conducted between August 1937 and February 1938 and the airframes were later handed over to the Luftwaffe test center at Rechlin where further testing was conducted.

Messerschmitt Bf 110E-2, 3C+LR of 7./NJG 2, pilot Ofw. Reinhard Kollack (49 kills), Mainz-Finthen airfield, Summer of 1942. Plane painted RLM 22 Schwarz. 10 beams (air victories) on fin. [Painted by Arkadiusz Wróbel]

The original design of the Messerschmitt Bf 110 called for in-line DB 600 engines with carburetors but testing was behind schedule and in the event the sub-contractors responsible for making the carburetors would not be able to meet the delivery deadlines. Since tests were almost complete on a direct fuel-injection version of the DB 601, the decision was made to use the lower-rated fuel-injected Jumo 210 G engines in the Bf 110. 86 were ordered and designated Bf 110B. They had a one-minute maximum take off rating of 730 hp and a 30 minute rating of 670 hp at 3,800 m. A three bladed, 3.1 m diameter, self-adjusting type VDM-VS propeller was used. The Bf 110B’s primary role was as a training machine. Production was started in April 1938 when the first two planes were built and finished with the 88th plane in February 1939. The prototype for the B version was the Bf 110B V7 (serial no. 917). The next three, numbers 918-920 received the pre-production designation B-0 while the rest were designated as B-1. Of the 88 planes built in total, the prototype, three pre-production models and 22 series models were built by Messerschmitt AG and the rest by Gotha. The Messerschmitt-built planes were assigned to test centers while those from the Gothaer Wagonfabrik went to front-line units. Among the test planes was a Bf 110B-1 (WNr. 928, D-AAPY) equipped with a Mk 101 30 mm cannon which was displayed to Adolf Hitler in Rechlin on 3 July 1939. Hitler was especially impressed by the new cannon and made the following statement: “I believe that this weapon is exceptionally important because I don’t think that we possess sufficient numbers of heavy guns for our aircraft.”
Bf 110B-1 (WNr. 920, D-ADJD) was tested from March 10, 1939 at the Tarnewitz test center with a Trommelgerät TG 65 rocket launcher for unguided rockets. The rocket launcher barrel was mounted in the forward fuselage section and contained 8 RZ 65 73 mm rockets with a range of 340 meters.


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