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Hi Matthew,
Chris Bobka emailed me with a link to your recent enquiry on the EAA website forum for ideas around a Yak 1, 3 or Yak 9 colour scheme applicable to a Taylor JT-1, the plans for which you've now acquired.
As we'd emailed each other numerous times on lightplane ideas for historical replicas, the Sperry M-1 being a typical example, I'd assumed you knew about my conversion of the JT-1 prototype, G-APRT, in the mid-1970s into a facsimile of the Yak 9D.
If you look at the picture of 'PRT in its current configuration with an open cockpit, you can still see the modified rudder which I fitted which is exactly the right shape for a Yak, unlike the more pointed rudder on the JT-1. I was able to camouflage the horn balance by arranging the yellow-outined red soviet star to follow the edge of the horn balance line so it was invisible when the rudder was in line with the fin.
The colour scheme was accurate and I recall that the colours were 'Datsun Green' and 'Triumph Tobacco Leaf' cellulose (with plasticiser) on upper surfaces and Arctic Blue underneath, providing the exact shades worn in summer by the 9 . My entire album of photographs of this aeroplane went missing in the early 1980s and I now only have a few left, some of which are attached herewith. The one of me strapping into the 'Yak' shows the scheme and the canopy as well as the Russian style numeral.
The canopy was a close fitting, sideways-hinged overwrap onto the rear decking with a sliding hood behind an 'armoured' windscreen. I lowered the seat to provide more canopy height clearance while providing a scale appearance to the canopy line. Later, when the people who bought the aeroplane from our Group 'restored it' they discarded the canopy altogther which is a pity as it was a work of art. They also reverted to the wheels being placed outside the undercarriage oleos rather than where I put them on the inside of the legs. In my case this altered the ground angle of the Taylor, steepening it, and also the legs themselves were extended by 3". The basic Taylor undercarriage is one of the worst I've seen and in the case of the prototype the 17 degree leg angle at the spar interface had eventuated in the attachment holes going 'oval' and the inner leg binding in the outer. The tendency for the Taylor to groundloop was exaggerated in the prototype because of the condition of the aeroplane when we bought it which was dire, and in some areas we explored, positively lethal. I also changed the attachment angle of the leg to the spar to 12-1/2 degrees, from memory, reducing the bending load on the leg. The result was not only no tendency to groundloop, but the flare on landing was now achievable, where previously it would hit tailwheel first if trying to flare at a resonable speed for three-pointing. It would also steer on the ground much more easily and could be pirhouetted neatly on a tight axis. The longer leg also created a more realistic appearance but of course was never officially accepted by the PFA.
The ailerons were a mess when we bought the aeroplane: massive mass balances having been attached to the spars to cure 'low speed flutter'. This I am convinced was induced by slacknees in the aileron circuit. Furthermore it was arranged such that the up-going aileron would reverse its direction with full control application, the 'up' travel on both ailerons being unequal by some 5 degrees each side. The external mass balance would contact and depress the fabric with full control applied and whoever had bolted them onto the spars had crushed the timber to half its thickness with the bolts. No rust proofing had been applied to the mass balances (the ailerons being totally overbalanced) and they'd not only rusted completely but the aileron spars themselves were showing signs of rot. The balances weighed about 10 lbs. each and there was absolutely no control feedback when ferry-flying it with these attached. I threw the lot away and built new ailerons with just a tiny amount of taper at the ends to reduce the 'plank' aspect of the wing. I also introduced internal mass balances based on those of the Taylor Titch which I presume are still on the aeroplane, just in case!
The aeroplane flew well and handled well but stall warning was non-existent and this has killed numerous JT-1 pilots, one quite recently. I would recommend stall-breaker strips inboard on the LE or some audible stall warning system.
There is another JT-1 flying in the UK in winter white scheme and red stars but with no other Yak conversion elements.
Finally I joined the EAA to answer this question on the Forum before I realised it was you asking the questions! I am waiting for the moderator to accept my application, but in the meantime, would you kindly pass this email onto the site for reference of the other members with the photographs herewith as there seems to be some interest in this conversion.
I am also attaching the images that Lynn sent, with the caveat (confirmed by Lynn) that the gear "retracting" in the Sport Aviation image is a bit of pre-photoshop magic. He and his partners had considered the using Bob Ladd's retractable gear modification for the Mono, but in the end did not go that route.