+++ DISCLAIMER +++
Nothing you see here is real, even though the conversion or the presented background story might be based historical facts. BEWARE!
Some background
The Focke Wulf Ta 338 originated as a response of request by the RLM in mid 1943 for an aircraft capable of vertical takeoff and landing (VTOL), optimized for the interceptor and point defense role and without a hazardous liquid rocket engine as means of propulsion. In the course of the year, several German manufacturers responded with a multitude of highly innovative if not unusual design, including Heinkel with the ducted fan project "Lerche", Rheinmetall-Borsig with a jet-powered tailsitter, and Focke Wulf. This company’s engineering teams submitted two designs: the revolutionary "Triebflügel" concept and the more conservative, yet still futuristic "P.03.10338" tail sitter proposal, conceived by Focke Wulf’s leading engineer Kurt Tank and Walter Kappus from BMW, responsible for the engine development.
The P.03.10338 was based on the proven Fw 190 fighter, but the similarities were only superficial. Only the wings and a part of the fuselage structure around the cockpit would be used, but Tank assumed that using existing parts and tools would appreciably reduce development and production time.
A great part of the fuselage structure had to be re-designed to accommodate a powerful BMW 803 engine and its integral gearbox for an eight-bladed contraprop.
The BMW 803 was BMW's attempt to build a high-output aircraft engine, primarily for heavy bombers, by basically "coupling" two BMW 801 engines back-to-back into a single and very compact power unit. The result was a 28-cylinder, four-row radial engine, each comprising a multiple-bank in-line engine with two cylinders in each bank, which, due to cooling concerns, were liquid cooled.
This arrangement was from the start intended to drive independent contra-rotating propellers, in order to avoid stiffness problems with the whole engine driving just a single crankshaft and also to simply convert the raw power of this unit into propulsion. The front half of the engine drove the front propeller directly, while the rear engine drove a number of smaller shafts that passed between the cylinders of the front engine before being geared back together to drive the rear prop. This complex layout resulted in a rather large and heavy gearbox on the front of the engine, and the front engine needing an extended shaft to "clear" that gearbox. The four-row 803 engine weighed 2,950 kg (6,490 lb) dry and 4,130 kg (9,086 lb) fully loaded, and initial versions delivered 3,900 PS (3,847 hp; 2,868 kW).
While the engine was heavy and there were alternatives with a better weight/output ratio (e. g. the Jumo 222), the BMW 803 was favored for this project because it was the most powerful engine available, and it was relatively compact so that it could be fitted into a fighter's airframe. On the P.03.10338 it drove an all-metal, eight-blade contraprop with a diameter of 4,25 m (13 ft 11 in).
In order to accept this massive engine, the P.03.10338’s structure had to be stiffened and the load-bearing structures re-arranged. The aircraft kept the Fw 190's wing structure and surface, but the attachment points at the fuselage had to be moved for the new engine mount, so that they ended up in mid position. The original space for the Fw 190's landing gear was used for a pair of radiator baths in the wings' inner leading edge, the port radiator catering to the front engine half while the radiator on starboard was connected with the rear half. An additional annular oil and sodium cooler for the gearbox and the valve train, respectively, was mounted in the fuselage nose.
The tail section was completely re-designed. Instead of the Fw 190's standard tail with fin and stabilizers the P.03.10338’s tail surfaces were a reflected cruciform v-tail (forming an x) that extended above and below the fuselage. On the four fin tips, aerodynamic bodies carried landing pads while the fuselage end contained an extendable landing damper. The pilot sat in a standard Fw 190 cockpit, and the aircraft was supposed to start and land vertically from a mobile launch pad. In the case of an emergency landing, the lower stabilizers could be jettisoned. Nor internal armament was carried, instead any weaponry was to be mounted under the outer wings or the fuselage, in the form of various “Rüstsätze” packages.
Among the many exotic proposals to the VTOL fighter request, Kurt Tank's design appeared as one of the most simple options, and the type received the official RLM designation Ta 338. In a rush of urgency (and maybe blinded by clever Wunderwaffen marketing from Focke Wulf’s side), a series of pre-production aircraft was ordered instead of a dedicated prototype, which was to equip an Erprobungskommando (test unit, abbreviated “EK”) that would evaluate the type and develop tactics and procedures for the new fighter.
Fueled by a growing number of bomber raids over Germany, the “EK338” was formed as a part of JG300 in August 1944 in Schönwalde near Berlin, but it took until November 1944 that the first Ta 338 A-0 machines were delivered and made operational. These initial eight machines immediately revealed several flaws and operational problems, even though the VTOL concept basically worked and the aircraft flew well – once it was in the air and cruising at speeds exceeding 300 km/h (186 mph).
Beyond the many difficulties concerning the aircraft’s handling (esp. the landing was hazardous), the lack of a landing gear hampered ground mobility and servicing. Output of the BMW 803 was sufficient, even though the aircraft had clear limits concerning the take-off weight, so that ordnance was limited to only 500 kg (1.100 lb). Furthermore, the noise and the dust kicked up by starting or landing aircraft was immense, and servicing the engine or the weapons was more complicated than expected through the high position of many vital and frequently tended parts.
After three Ta 338 A-0 were lost in accidents until December 1944, a modified version was ordered for a second group of the EK 338. This led to the Ta 338 A-1, which now had shorter but more sharply swept tail fins that carried single wheels and an improved suspension under enlarged aerodynamic bodies.
This machine was now driven by an improved BMW 803 A-2 that delivered more power and was, with an MW-50 injection system, able to produce a temporary emergency output of 4.500 hp (3.308 kW).
Vertical start was further assisted by optional RATO units, mounted in racks at the rear fuselage flanks: either four Schmidding SG 34 solid fuel booster rockets, 4.9 kN (1,100 lbf) thrust each, or two larger 9.8 kN (2,203 lbf) solid fuel booster rockets, could be used. These improvements now allowed a wider range of weapons and equipment to be mounted, including underwing pods with unguided rockets against bomber pulks and also a conformal pod with two cameras for tactical reconnaissance.
The hazardous handling and the complicated maintenance remained the Ta 338’s Achilles heel, and the tactical benefit of VTOL operations could not outbalance these flaws. Furthermore, the Ta 338’s range remained very limited, as well as the potential firepower. Four 20mm or two 30mm cannons were deemed unsatisfactory for an interceptor of this class and power. And while bundles of unguided missiles proved to be very effective against large groups of bombers, it was more efficient to bring these weapons with simple and cheap vehicles like the Bachem Ba 349 Natter VTOL rocket fighter into target range, since these were effectively “one-shot” weapons. Once the Ta 338 fired its weapons it had to retreat unarmed.
In mid 1945, in the advent of defeat, further tests of the Ta 338 were stopped. I./EK338 was disbanded in March 1945 and all machines retreated from the Eastern front, while II./EK338 kept defending the Ruhrgebiet industrial complex until the Allied invasion in April 1945. Being circled by Allied forces, it was not possible to evacuate or destroy all remaining Ta 338s, so that at least two more or less intact airframes were captured by the U.S. Army and later brought to the United States for further studies.
General characteristics:
Crew: 1
Length/height on the ground: 10.40 m (34 ft 2 in)
Wingspan: 10.50 m (34 ft 5 in)
Fin span: 4:07 m (13 ft 4 in)
Wing area: 18.30 m² (196.99 ft²)
Empty weight: 11,599 lb (5,261 kg)
Loaded weight: 16,221 lb (7,358 kg)
Max. takeoff weight: 16,221 lb (7,358 kg)
Powerplant:
1× BMW 803 A-2 28-cylinder, liquid-cooled four-row radial engine,
rated at 4.100 hp (2.950 kW) and at 4.500 hp (3.308 kW) with emergency boost.
4x Schmidding SG 34 solid fuel booster rockets, 4.9 kN (1,100 lbf) thrust each, or
2x 9.8 kN (2,203 lbf) solid fuel booster rockets
Performance:
Maximum speed: 860 km/h (534 mph)
Cruise speed: 650 km/h (403 mph)
Range: 750 km (465 ml)
Service ceiling: 43,300 ft (13,100 m)
Rate of climb: 10,820 ft/min (3,300 m/min)
Wing loading: 65.9 lb/ft² (322 kg/m²)
Armament:
No internal armament, any weapons were to be mounted on three hardpoints (one under the fuselage for up to 1.000 kg (2.200 lb) and two under the outer wings, 500 kg (1.100 lb) each. Total ordnance was limited to 1.000 kg (2.200 lb).
Various armament and equipment sets (Rüstsätze) were tested:
R1 with 4× 20 mm (.79 in) MG 151/20 cannons
R2 with 2x 30 mm (1.18 in) MK 213C cannons
R3 with 48x 73 mm (2.874 in) Henschel Hs 297 Föhn rocket shells
R4 with 66x 55 mm (2.165 in) R4M rocket shells
R5 with a single 1.000 kg (2.200 lb) bomb under the fuselage
R6 with an underfuselage pod with one Rb 20/20 and one Rb 75/30 topographic camera
The kit and its assembly:
This purely fictional kitbashing is a hardware tribute to a highly inspiring line drawing of a Fw 190 VTOL tailsitter – actually an idea for an operational RC model! I found the idea, that reminded a lot of the Lockheed XFV-1 ‘Salmon’ prototype, just with Fw 190 components and some adaptations, very sexy, and so I decided on short notice to follow the urge and build a 1:72 version of the so far unnamed concept.
What looks simple (“Heh, it’s just a Fw 190 with a different tail, isn’t it?”) turned out to become a major kitbashing. The basis was a simple Hobby Boss Fw 190 D-9, chose because of the longer tail section, and the engine would be changed, anyway. Lots of work followed, though.
The wings were sliced off and moved upwards on the flanks. The original tail was cut off, and the cruciform fins are two pairs of MiG-21F stabilizers (from an Academy and Hasegawa kit), outfitted with reversed Mk. 84 bombs as aerodynamic fairings that carry four small wheels (from an 1:144 T-22M bomber) on scratched struts (made from wire).
The cockpit was taken OOB, only a pilot figure was cramped into the seat in order to conceal the poor interior detail. The engine is a bash from a Ju 188’s BMW 801 cowling and the original Fw 190 D-9’s annular radiator as well as a part of its Jumo 213 cowling. BMW 801 exhaust stubs were inserted, too, and the propeller comes from a 1:100 VEB Plasticart Tu-20/95 bomber.
Since the BMW 803 had liquid cooling, radiators had to go somewhere. The annular radiator would certainly not have been enough, so I used the space in the wings that became available through the deleted Fw 190 landing gear (the wells were closed) for additional radiators in the wings’ leading edges. Again, these were scratched with styrene profiles, putty and some very fine styrene mesh.
As ordnance I settled for a pair of gun pods – in this case these are slipper tanks from a Hobby Boss MiG-15, blended into the wings and outfitted with hollow steel needles as barrels.
Painting and markings:
Several design options were possible: all NMF with some colorful markings or an overall RLM76 finish with added camouflage. But I definitively went for a semi-finished look, inspired by late WWII Fw 190 fighters.
For instance, the wings’ undersides were partly left in bare metal, but the rudders painted in RLM76 while the leading edges became RLM75. This color was also taken on the wings’ upper sides, with RLM82 thinly painted over. The fuselage is standard RLM76, with RLM82 and 83 on the upper side and speckles on the flanks. The engine cowling became NMF, but with a flashy ‘Hartmann Tulpe’ decoration.
Further highlights are the red fuselage band (from JG300 in early 1945) and the propeller spinner, which received a red tip and segments in black and white on both moving propeller parts. Large red “X”s were used as individual aircraft code – an unusual Luftwaffe practice but taken over from some Me 262s.
After a light black ink wash some panel shading and light weathering (e.g. exhaust soot, leaked oil, leading edges) was done, and the kit sealed under matt acrylic varnish.
Building this “thing” on the basis of a line drawing was real fun, even though challenging and more work than expected. I tried to stay close to the drawing, the biggest difference is the tail – the MiG-21 stabilizers were the best option (and what I had at hand as donation parts), maybe four fins from a Hawker Harrier or an LTV A-7 had been “better”, but now the aircraft looks even faster. ;)
Besides, the Ta 338 is so utterly Luft ’46 – I am curious how many people might take this for real or as a Hydra prop from a contemporary Captain America movie…
