Aeroworks Yak 54 ARF-QB .60-.90 Size Build
06 March 2016 - After having moved south in 2013 it took me a bit to get back into flying. I had managed to bring three planes with me but I was getting the itch to build a new one last year. After the great success with the Aeroworks 300 60-90 size I was definitely up for another similar sized Aeroworks. Then I saw they had the Yak 54 on sale, perfect! I have been meaning to get a Yak 54 for some time. I had a brand new OS FS-95V four stroke engine already that seemed would fit the bill.
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Unfortunately I have to report that this build did NOT go as smoothly as the Extra did. There are a few glitches in the design IMHO. I actually wasn't going to write this article up at all originally because of these issues. However as good as Aeroworks is there no point in not being honest. Besides maybe knowing this ahead of time may help someone else looking into this plane. Knowing what you're getting into is never a bad thing.
So lets get the glitches out of the way first. Essentially there are two in my case. First is the engine specs vs the firewall to thrust washer distance. On the Aerworks Extra 300 I built shoehorning the OS FS-91 Surpass II in there was tight. The engine was as far back as it could go but it just made it to the spec'd distance and the plane balanced without weight. On the Yak54 however the OS FS-95V even as far back as it can go, with socket head screws replaced with button heads and part of the engine mount shaved to get the most clearance the intake pipe to the carb it touching the firewall and the thrust washer is still far forward of where it should be. You can see it in the pictures below.
This may not be an issue with a smaller four stroke engine however I think to get satisfactorily smaller you would need to go too small for the plane. It would also not be an issue with a two stroke engine that does not have a rear carburetor. I would say if you were to go with gas over glow fuel you may want to avoid rear carburetor engines as well and go for something like an Evolution 20cc that has the front carburetor like a glow two stroke does. Also clearly this is not an issue with electric power either. This is strictly an issue for larger rear carburetor engines on this model. If you want one of those engines in a plane this size the Aeroworks Extra 300 is a better choice and even there I can tell you it's tight.
The second issue I'm afraid is universal and affects everyone. Personally I find it to be a surprising design flaw coming from a company as good as Aeroworks. The following two pictures are of the elevator sections of the Aeroworks Extra 300 (orange) and the Aeroworks Yak 54 (red);
Now those of you who are familiar with the Aeroworks designs know that you have to put the elevator control surface through the slot first then put the horizontal stabilizer in and then you can get them hinged up. In any case this is a tedious task. However if you note the Extra 300's setup there is a slot in the back where you can slide the elevator back some and give you at least some room to do this. In fact the overall opening is larger as well and more suitably shaped.
With the Yak 54 as you can see there is literally NO ROOM to accomplish this task. It seems like an issue they should be aware of given that several of the images in the manual where they show you assembling the rear of the plane show a slot more like the Extra (see image of manual below) while other show the simple circle cut. I'd have cut the slot back myself but there is not really any room to do so without going all the way through and the plane is clearly not designed to be cut that way.
So basically to get by this the only way I found was to rotate the elevator backwards under the horizontal stabilizer (over would work too I suppose) and fold the hinges and put them in both sides at once. This is NOT a simple task as it sounds. Particularly to do it without creasing the hinges themselves in the process. Be prepared to curse.
Now other than those two things the plane went together great. I did have to add lead in the tail due to the engine being so far forward but only an ounce or so. Which stinks but the plane was pretty light to begin with and the little extra weight isn't going to hurt anything.
So by reading this you might get the idea that I am disappointed in the plane overall but seriously, I am not. Other than those two things the plane went together well and more importantly flies like it's on rails. It handles very responsively and yet lands like butter. To top it off, even without vinyl decals which I never buy until after I know a plane will fly, she is a looker. The plane looks way nicer in person than it does on their web page. If I bought it again I would power it different for sure but I would still get it again. Even knowing hinging the elevator was going to be a bit of a science experiment.
The first video on this page is the maiden flight. Clearly my flight skills are still green after being out of practice but the plane handles well. Below is the second flight that day.