The He 111 and the FW 200 at Air Forces Scientific Research Institute
If, with reference to some aircraft, Soviet engineers were interested only in individual components, then others were of interest as a whole. There was a long-standing requirement to carry out a complete flight test program of the He 111 at the Air Forces Scientific Research Institute. Understandably, it was difficult to base results on the examination of the "Spanish prisoner" captured in late 1937. German engineers had introduced too many changes into the aircraft design. In addition, the Germans employed the Heinkel for a wide variety of missions: it served as a bomber, reconnaissance aircraft, transport aircraft, torpedo carrier, and mine layer. It could be encountered in the East as often as the more modern and faster Ju 88. Several times damaged machines landed in territory Soviet troop units controlled, and were carefully examined. But, as a rule, the situation would not allow aircraft to be evacuated deep into the rear area.
Two Heinkels that Red Army soldiers captured on an airfield west of Stalingrad were selected for this testing program. After reconditioning, an He 111H-6 bomber was turned over to Chkalovskaya for testing on 24 February 1943, but, after the third flight, an engine malfunctioned. Institute engineers then began working with the second aircraft - an He 111H-11, which had its worn-out engines replaced by those from another Heinkel. In May 1943, this airplane safely completed the program (lead engineer Major G. V. Gribakin, lead pilot Lieutenant Colonel G. A. Ashitkov).
Testing showed that, despite its reheated Jumo 211 -F-1 engines with a takeoff power of 13 5 Ohp, the HelllH-11 had maximum level speed, rate of climb, and ceiling which were rather low for the year 1942. The German bomber lagged behind the domestic series-produced 11-4 by 11-19 km/h in speed (depending on altitude) and by 3.9 minutes in climbing to 5000 meters (given a normal flight weight for both planes). It also compared unfavorably with the Soviet bomber in cruising range with a 1000-kilogram bomb load.
But, in some respects, the Heinkel had definite advantages. It had improved defensive armament with an increased number of guns, including the MG 131 machine gun and MG-FF cannon in a semi-fixed mount. Collimating sights replaced the simple ring and bead gun sights. The ammunition supply for the semi-fixed machine gun mount on Soviet bombers permitted 15 seconds of uninterrupted fire, whereas a German gunner could fire for 75 seconds before running out of ammunition.
Engineer-Major Gribakin did not think that the German airplane was sufficiently armored in area and in thickness for protection against large-caliber rounds and projectiles (the weight of armor varied from 270 to 315 kilograms, depending on bomber modification). Nevertheless, armor plates protected the crew, the most important and vulnerable units of the power plant, and the crew working area, thus enhancing the bomber's viability. Striving to increase the bomb load and size, German designers decided not to make complicated modifications to the He 111H-11 fuselage and switched to external bomb racks at the expense of aerodynamic qualities. An additional fuel tank took the place of bomb bay in the fuselage.
The Il'yushin Experimental Design Bureau installed VISH-61IF-1 feathering propellers (instead of the standard VTSH-2 3) on an 11-4 bomber being tested at the Air Forces Scientific Research Institute almost simultaneously with the Heinkel. These propellers began to be used after examining German know-how when a disabled engine propeller was feathered to facilitate flight on one working engine. The testing team thought that the main 11-4 defects were insufficient longitudinal stability, ducking down when the split landing flaps were extended, inconvenient radiator gill control, and weak undercarriage wheels. All this made the 11-4 more difficult than the He 111 to handle.
Air Forces Scientific Research Institute personnel impatiently awaited the arrival of the four-engine Kondor. Engineer-Major Gribakin (lead pilot Colonel Kabanov) also carried out the trials on Fw 200 Kondor No. 0034 captured near Stalingrad. Soviet reports of the first period of the war often mentioned Kondor flights over different areas of the Soviet-German front. In reality, these machines were of limited use in setting up air bridges at Demyansk and Stalingrad. Many institute specialists remembered the civil Kondor that brought German Foreign Minister von Ribbentrop to Moscow in August 1939.
Prior to the onset of testing, the Russian engineers noted that the Kondor bore significant resemblance to the American Douglas DC-3 in cabin layout and arrangement of inner compartments. This was an improvised conversion of a passenger plane into a long-range bomber and the Luftwaffe did not get a full-fledged military aircraft. Indeed, despite its large size, the crew compartment was very cramped, which made it especially difficult for crewmembers (the navigator-bombardier, in particular) on long endurance flights. The crew commander could not reach the controls of some systems such as the backup electrical pumps, emergency brakes, and so forth. The pilots had absolutely no view to the rear.
In general, the Heinkel outperformed the Kondor where handling, visibility, and power plant quality were concerned. Our test pilots compared Fw 200C flight characteristics with those of the Pe-8 4 AM-35A and concluded that the V. M. Petlyakov bomber significantly surpassed the German aircraft in maximum speed, operating ceiling, number and placement of weapons, and in their calibers.39 The operating ceiling of 6850 meters was considered for night sorties in areas where flak was intense. In all aspects, the Kondor did not compare favorably to American Liberators and Flying Fortresses, which the Soviet Union repeatedly had tried to buy.
The most interesting things on this four-engine German aircraft were the carefully conceived and manufactured electrical components, bombsights for low-altitude bombing, and a simple and reliable thermal deicer. In late April 1943, all these units, along with an EZ-2 radio compass, Lorenz blind-landing equipment, Askania automatic course device, Bauer-Sperry artificial horizon indicator, and Patin electrical remote magnetic compass, were handed over to the appropriate research institutes in 1943 for detailed examination and use.
- "The German Imprint on the History of Russian Aviation " /D.A. Sobolev, D.B. Khazanov/