FW 190 D9
Posted by Velka Mrkev on 20.10.2005 12:18
Focke-Wulf Fw 190D
The "Dora 9"
The Fw 190D "long-nose" version was an adaptation of the radial-engined Fw 190A to the Junkers Jumo 213 twelve-cylinder liquid-cooled engine. In many respects, the "Dora" was the most successful version of the Focke-Wulf fighter to attain service in quantity.
In 1943, the Luftwaffe was faced with a desperate need for fighters with better high-altitude performances to face the threat of Allied bombers. By that time, the Luftwaffe was aware of the existence of the B-29, and they were also aware that the existing Fw 190 would be incapable of effectively intercepting this American bomber at the altitudes at which it was supposedly capable of operating. Consequently, Dipl.-Ing. Kurt Tank undertook the development of a high altitude version of his Fw 190 fighter to meet the threat.
Tank was convinced that the BMW-801 air-cooled radial would never achieve the required high-altitude performance, and decided that only a liquid-cooled engine would do. Tank proposed that Daimler Benz DB 603 engine be used, but this engine was looked upon with disfavor by the Reichluftfahrtministerium (State Ministry of Aviation, better known as the RLM) for what were basically political rather than technical reasons. Consequently, Tank was told to adapt the existing BMW 801 air cooled radial or use the Junkers Jumo 213 liquid-cooled Vee. As a concession to Tank, he was allowed to work on a DB 603-powered version, but it was made clear to him that it would be only a low-priority project.
Three alternative proposals were considered: the Fw 190B powered by a turbosupercharged BMW-801, the Fw 190C powered by a DB 603, and the Fw 190D powered by a Jumo 213. The Fw 190B and C both ran into an extensive series of teething problems, and, in the event, never entered production. Priority was therefore given to the Fw 190D even though Tank felt that that the DB 603 was a better high-altitude engine than the Jumo 213 and had greater development potential. In addition, it was anticipated that the Jumo 213 would be available sooner than the DB 603 engine, which was still regarded as being "chancy" by the RLM. Tank had always viewed the "Dora" as only an interim type, pending the availability of the DB-603-powered version, which was eventually to evolve into the Ta 152.
The Jumo engine had a nose radiator housed in a short annular duct. In order to compensate for the longer nose, the rear fuselage was also lengthened, overall length becoming 33 feet 11 inches (as compared with 29 feet 0 inches for the Fw 190A version). The vertical fin was increased in width. The Jumo engine was installed as a complete "power egg", being attached by four bolts to the fireproof bulkhead. It drove a three-bladed "paddle" propeller.
There were a small number of Fw 190D-0 and D-1 aircraft built for service evaluation and delivered during the spring and summer of 1943. For some odd reason, the designations Fw 190D-2 thru 8 were skipped, and the first production version of the "Dora" was the Fw 190D-9, which attained production status in the early summer of 1944. It was powered by a Jumo 213A-1 engine rated at 1776 hp for takeoff and 1600 at 18,000 feet. However, with MW 50 (water/methanol) injection, it could give 2240 hp at sea level and 2000 hp at 11,150 feet. The boost could not be used longer than ten minutes at a time, but there was sufficient MW 50 fuel for a maximum of 40 minutes use. Armament was two 20-mm MG 151 cannon in the wing roots with 200 rpg and two 13-mm MG 131 machine guns with 475 rpg mounted in the upper fuselage deck. A 1102-pound bomb could be carried on an underwing rack. Maximum speed was 357 mph at sea level, 397 mph at 10,830 feet, 426 mph at 21,650 feet, and 397 mph at 32,800 feet. An altitude of 6560 feet could be reached in 2.1 minutes, and 32,801 feet could be attained in 16.8 minutes. Range was 520 miles at 18,500 feet on internal fuel. Weights were 7694 lbs empty, 9840 lbs normal loaded, and 10,670 lbs maximum. The aircraft was well-armored, having a 14-mm plate for the pilot's head and shoulders, and an 8-mm plate for the seat back and surrounding area. The engine was protected by armor rings around the cowling.
Delivery of the Fw 190D-9 began in August 1944. The first Gruppe to convert to the "Dora-9" was III/JG 54. Their initial assignment was to fly "top cover" for Me 262 jet fighters during takeoff when the jet fighters were specially vulnerable because of their poor acceleration. At first, Luftwaffe pilots were somewhat suspicious of their new fighter, since the Jumo 213 was thought to be only a "bomber" engine. However, it soon became apparent that they had a winner on their hands. The "Dora" could out-climb and out-dive its BMW 801-powered predecessor with ease, and it possessed an excellent turning rate at speed. An experienced pilot could pull a tighter turn in a D-9 than he could with the BMW-powered FW-190A. The general opinion of the pilots who flew the FW 190D-9 was that it was the finest propeller-driven fighter available to the Luftwaffe during the entire war. In fact, many of its pilots considered it more than a match for the redoubtable P-51D Mustang.
The D-9 also participated in Operation Bodenplatte, a mass attack by several hundred Luftwaffe aircraft on Allied airfields in Belgium, France, and the Netherlands on the first of January, 1945.
Very early in the production run of the "Dora-9", the original Fw 190Astyle cockpit canopy was replaced by a blown hood similar to that used on the Fw 190F fighter-bomber.
The Fw 190D-10 was an experimental version of the D-9 with an engine-mounted MK 108 cannon and two MG 151 cannon in the wing roots. Only two of these were built.
The Fw 190D-11 was powered by the Jumo 213F with MW 50 boost. The fuselage-mounted guns were eliminated, and there were two MG 151s in the wing roots and two MK 108s in the outer wings. Only seven prototypes were built.
The Fw 190D-12 was a fighter-bomber variant, which differed from the D-9 by having a three-stage supercharged Jumo 213F-1 engine rated at 2060 hp for takeoff mounted in a new, more extensively armored cowling. Armanent was one engine-mounted 30-mm MK 108 cannon and two 20-mm MG 151s in the wing roots. Although primarily a ground-attack plane, the D-12 also made an effective fighter and could attain 453 mph at 37,000 feet when MW 50 boost was used. Production began in March 1945 at the Arado and Fieseler plants, but only a few were delivered.
The D-13 differed from the D-12 by having a Jumo 213EB engine and by having a 20-mm engine-mounted MG 151 cannon in place of the 30-mm MK 108 unit. However, only a couple of prototypes were built.
In the late autumn of 1944, the Technische Amt decided to switch to the Daimler-Benz DB 603 engine for future Fw-190D production. A couple of production Fw 190D-9s were re-engined with the DB 603AE, and during tests one of them clocked 435 mph at 32,800 feet. Plans were made to produce the fighter in series with the DB603E or DB 603LA as the Fw 190D-14 and with the DB 603EB or DB 603G as the Fw 190D-15, but the war ended before these plans could be brought to fruition.
Somewhere between 650 and 700 "Doras" were built before the occupation of Focke-Wulf factories by Allied forces brought production to an end.
There is an Fw 190D-9 on display at the WPAFB Museum in Dayton, Ohio. An Fw 190D-12 is on display at the Champlin Fighter Museum at Falcon Field, Mesa, Arizona.
I'll talk about the Ta 152 later.
Sources:
· Warplanes of the Third Reich, William Green, Doubleday, 1971.
· Famous Fighters of the Second World War, William Green, Doubleday 1967.
· The Focke-Wulf 190--A Famous German Fighter, Heinz Nowarra, Harleyford, 1965.