1:72 Rostov Tilt Rotor Aircraft Company РТАК-30 (NATO ASCC code “Hemlock”); 3rd prototype "33 Yellow" during state acceptance trials; Zhukovsky (Moscow Oblast), 1987 (Whif/kitbashing) - WiP
The kit and its assembly:
This exotic, fictional aircraft-thing is a contribution to the “The Flying Machines of Unconventional Means” Group Build at whatifmodelers.com in early 2019. While the propulsion system itself is not that unconventional, I deemed the quadrocopter concept (which had already been on my agenda for a while) to be suitable for a worthy submission.
The Mil Mi-30 tiltrotor aircraft, mentioned in the background above, was a real project – but my alternative combat vintoplan design is purely speculative.
I had already stashed away some donor parts, primarily two sets of tiltrotor backpacks for 1:144 Gundam mecha from Bandai, which had been released recently. While these looked a little toy-like, these parts had the charm of coming with handed propellers and stub wings that would allow the engine nacelles to swivel.
The search for a suitable fuselage turned out to be a more complex safari than expected. My initial choice was the spoofy Italeri Mi-28 kit (I initially wanted a staggered tandem cockpit), but it turned out to be much too big for what I wanted to achieve. Then I tested a “real” Mi-28 (Dragon) and a Ka-50 (Italeri), but both failed for different reasons – the Mi-28 was too slender, while the Ka-50 had the right size – but converting it for my build would have been VERY complicated, because the engine nacelles would have to go and the fuselage shape between the cockpit and the fuselage section around the original engines and stub wings would be hard to adapt. I eventually bought an Italeri Ka-52 two-seater as fuselage donor.
In order to mount the four engines to the fuselage I’d need two pairs of wings of appropriate span – and I found a pair of 1:100 A-10 wings as well as the wings from an 1:72 PZL Iskra (not perfect, but the most suitable donor parts I could find in the junkyard). On the tips of these wings, the swiveling joints for the engine nacelles from the Bandai set were glued. While mounting the rear wings was not too difficult (just the Ka-52’s OOB stabilizers had to go), the front pair of wings was more complex. The reason: the Ka-52’s engines had to go and their attachment points, which are actually shallow recesses on the kit, had to be faired over first. Instead of filling everything with putty I decided to cover the areas with 0.5mm styrene sheet first, and then do cosmetic PSR work. This worked quite well and also included a cover for the Ka-52’s original rotor mast mount. Onto these new flanks the pair of front wings was attached, in a mid position – a conceptual mistake…
The cockpit was taken OOB and the aircraft’s nose received an additional thimble radome, reminiscent of the Mi-28’s arrangement. The radome itself was created from a German 500 kg WWII bomb.
At this stage, the mid-wing mistake reared its ugly head – it had two painful consequences which I had not fully thought through. Problem #1: the engine nacelles turned out to be too long. When rotated into a vertical position, they’d potentially hit the ground! Furthermore, the ground clearance was very low – and I decided to skip the Ka-52’s OOB landing gear in favor of a heavier and esp. longer alternative, a full landing gear set from an Italeri MiG-37 “Ferret E” stealth fighter, which itself resembles a MiG-23/27 landing gear. Due to the expected higher speeds of the vintoplan I gave the landing gear full covers (partly scratched, plus some donor parts from an Academy MiG-27). It took some trials to get the new landing gear into the right position and a suitable stance – but it worked. With this benchmark I was also able to modify the engine nacelles, shortening their rear ends. They were still very (too!) close to the ground, but at least the model would not sit on them!
However, the more complete the model became, the more design flaws turned up. Another mistake is that the front and rear rotors slightly overlap when in vertical position – something that would be unthinkable in real life…
With all major components in place, however, detail work could proceed. This included the completion of the cockpit and the sensor turrets, the Ka-52 cannon and finally the ordnance. Due to the large rotors, any armament had to be concentrated around the fuselage, outside of the propeller discs. For this reason (and in order to prevent the rear engines to ingest exhaust gases from the front engines in level flight), I gave the front wings a slightly larger span, so that four underwing pylons could be fitted, plus a pair of underfuselage hardpoints.
The ordnance was puzzled together from the Italeri Ka-52 and from an ESCI Ka-34 (the fake Ka-50) kit.