DONE @p.3 +++ 1:72 Kaman K-1300 ’K-Cobra’, operated by Heliswiss, 2005

[Dizzyfugu]

Second entry, and it already made (very) slow progress.  The GB offers a welcome occasion and motivation to tackle a what-if project that had been on my list for a long while: a crane helicopter conversion of a HueyCobra, inspired by the Mil Mi-10K helicopter – I had built a 1:100 VEB Plasticart kit MANY years ago and still remembered the helicopter's unique ventral cabin under the nose with a rearward-facing second pilot. I always thought that the AH-1 might be a good crane helicopter, too, somewhat inspüired by Kaman's dedictaed K-1200 helicopter, and esp. the USMC's twin-engine variant appeared like a good starting point. So, why not combine everything into a fictional model?

With this plan the basis became a Fujimi 1:72 AH-1J and lots of donor parts to modify the basic hull into "something else".   

Things started with the removal of the chin turret and part of the lower front hull to make space for the ventral glass cabin. The openings for the stub wings were faired over and a different stabilizer (taken from a Revell EC 135, including the end plates) was implanted. The attachment points for the skids were filled and a styrene tube was inserted into the rotor mast opening to later hold the new four-blade rotor. Another styrene tube with bigger diameter was inserted into the lower fuselage as a display holder adapter for later flight scene pictures. Lead beads filled the nose section to make sure the CraneCobra would stand well on its new legs, with the nose down. The cockpit was basically taken OOB, just the front seat and the respective gunner dashboard was omitted.


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr

One of the big challenges of this build followed next: the ventral cabin. Over the course of several months, I was not able to find a suitable donor, so I was forced to scratch the cabin from acrylic and styrene sheet. Size benchmark became the gunner's seat from the Cobra kit, with one of the OOB pilots seated. Cabin width was less dictated through the fuselage, the rest of the cabin's design became a rather simple, boxy thing – not pretty, but I think a real-life retrofitted cabin would not look much different? Some PSR was done to hide the edges of the rather thick all-clear walls and create a 3D frame - a delicate task. Attaching the completed thing with the second pilot and a dashboard under the roof to the Cobra's lower hull and making it look more or less natural without major accidents was also a tricky and lengthy affair, because I ignored the Cobra's narrowing nose above the former chin turret. 

1
:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr

More coming soon... 

[PR19_Kit]

WOWEEEEEE, a Mini-Crane! 

[Dizzyfugu]

Yeah! 

"It's a Cobra, Jim, but not as we know it!"

[kerick]

Quite a while ago I heard of a small company that converted a Cobra to an aerial crane. If you can do it with a Huey why not a Cobra? Of course I can't find it now.

[jcf]

Cool

K-Max is one of my favorite helicopters. 

[jcf]

Quite a while ago I heard of a small company that converted a Cobra to an aerial crane. If you can do it with a Huey why not a Cobra? Of course I can't find it now.

Give a Cobra the engine and big rotor of the Bell 214B "BigLifter" and you'd have a serious
weight lifter for slung loads.

214B
Powerplant: 1 × T5508D, 2,930 shp (2,180 kW)
Main rotor diameter: 50 ft (15 m)
Main rotor area: 1,963.75 sq ft (182.438 m2)
Blade section: Wortmann FX 69-H-098

AH-1S engine and rotor specs for comparison:
Powerplant: 1 × T53-L-703, 1,800 shp (1,300 kW)
Main rotor diameter: 44 ft 0 in (13.4 m
Main rotor area: 1,520 sq ft (141 m2)
Blade section: NACA 0009.3 mod


 

[Dizzyfugu]

Ah, discussions...    The rotor system was created in parallel, I wanted "something different" from the UH-1 dual-blade rotors. The main rotor hub was taken from a Mistercraft 1:72 Westland Lynx (AFAIK a re-boxed ZTS Plastyk kit), which included the arms up to the blades. The hub was put onto a metal axis, with a spacer to make it sit well in the new styrene tube adapter inside of the hull, and some donor parts from the Revell EC 135. Deeper, tailored blades were glued to the Lynx hub, actually leftover parts from the aforementioned wrecked VEB Plasticart 1:100 Mi-10, even though their length had to be halved (what makes you aware how large a Mi-6/10 is compared with an AH-1!). The tail rotor was taken wholesale from the Lynx and stuck to the Cobra's tail with a steel pin.


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr

The ventral cabin also made progress - lots of masking involved, though:


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr

With the cabin defining the ground helicopter's clearance, it was time for the next donors: the landing gear from an Airfix 1:72 Kamow Ka-25, which had to be modified further to achieve a proper stance. The long main struts were fixed to the hull, their supporting struts had to be scratched, in this case from steel wire. The front wheels were directly attached to the ventral cabin (which might contain in real life a rigid steel cage that not only protects the second crew member but could also take the front wheels' loads?). Looks pretty stalky!
Between the spindly struts a pair of auxiliary tanks (also inspired by the Mi-10), capsule-shaped drop tanks left over from a Hasegawa Ki-61, were added to the lower fuselage flanks. Under the hull, a massive hook and a fairing for the oil cooler were added.


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr

[jcf]

Your rotor assembly doesn't look too dissimilar from that of the AH-1Z.

[Dizzyfugu]

Well, somewhat. But that's just a coincidence, due to the Lynx hub's long arms that had to accept the Mi-10 blade roots. Worked better than expected, though, and it looks quite good on the Cobra (pics coming soon).

This heli creation looks really odd, but I like it! 

[PR19_Kit]

It looks like it'll be an absolute BLINDER when it's done. 

(And I don't mean a Tu-22....)

[loupgarou]

Very good. The loong legs are difficult to build strong enough. I have wanted for a long time to build the long legged version of the Mil 10 (Plasticart), but what blocked mewasthe idea of cutting and bending many pieces of brass wire at exactly the same length and angle. 

[Dizzyfugu]

About to add some paint, with the main rotor dry-fitted.


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr

The VEB Plasticart is a messy affair. The tail rotor consists of five single parts and the landing gera legs come in segments - there's NO main strut to which you add some braces, no, it consists of a zillion single short struts and pins. Horror!

[Dizzyfugu]

...and now with some white on the belly:


1:72 Kaman K-1300 'K-Cobra'; operated by Heliswiss AG, Belp (Switzerland), 2005 (What-if/modified Fujimi kit) - WiP by Dizzyfugu, on Flickr

[PR19_Kit]

The VEB Plasticart is a messy affair.

Typical of VEB kits sadly, some of their 1/100 airliners bear only a slight resemblance to the real thing, apart from the Tu-134 which is rather good. 

[kerick]

This is looking outstanding!!!
Some real whiffing going on here.
The Cobra converted to aerial crane owner's main claim was that so much weight was saved by removing military equipment and the smaller fuselage enabled it to lift more than a basic Huey at that time. Wish I could find that article but getting to be quite a while ago now.