...bzw. mit vollem Titel: eine 1:72 Focke Wulf Ta 338 A-1/R2, „Rote X+ ―” des II./EK338 (Teil des JG300), Deutsche Luftwaffe; Dortmund, April 1945
<b>Some background</b>
<i>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.</i>
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
Dieses Ding ist natürlich völlig fiktiv - falls jemand Zweifel haben sollte - und basiert auf einer Zeichnung eines Modellbau-Kollegen, die eigentlich die Basis für ein RC-Modell(!!!) ist:
Ich fand das Konzept aber so bekloppt und spannend, dass ich kurzerhand ein 1:72-Modell davon - zumindest annäherungsweise - bauen wollte. Na ja, und hier das Ergebnis der Frankensteinerei...
Die Basis war eine Hobby Boss Fw 190 D-9, aber es blieb kaum ein Stein auf dem anderen. Die Tragflächen wurden versetzt, die Haube verlängert, ein Kontraprop implantiert, die Finnen stammen von zwei MiG-21Fs. Etwas schnittiger als die Vorlage, aber das Beste zur Hand und ich wollte nicht scratchen.
Neu ist das Fahrwerk, dessen Fehlen ich als eher unpraktisch erachtete, und Kühler in den Tragflächen anstelle des ursprünglichen Fahrwerkes.
Der Anstrich ist eine freie Interpretation später Fw 190, die teilweise nur mit Grundierung oder gar blank in den Dienst gescheucht wurden. Die Markierungen sind ein wilder Mix, so passen die Hartmann-Tulpe und die "Flügel" des JG2 an den Auspuffrohren sicher nicht zusammen - es sollte schnittig und ein wenig nach Pop-Art aussehen, denn das Ding sah immer mehr wie ein Prop aus einem Captain-America-Film aus... Science Fiction halt.
Thema: What if? Focke Wulf Ta 338 VTOL-Jäger (Gelesen 7287 mal)