The Sky Eye arrived from HobbyKing in a non-descript box after a week long shipping delay from HobbyKing. Upon removing the parts from the box, I was a little surprised at how complete this plane already is:
Really all that needed to be done was gluing on the tail, installing the nose dome, installing the control surface horns and installing/configuring the electronics.
I think it is a little funny that even with only four basic building steps, I still had a lot of trouble with one of them because of botched hardware.
Specifically, the threaded piano wire supplied from the factory that you screw the plastic clevis’ onto were WAY too long. Like half an inch for every single control surface. The flap rods were so long that I had to dremel off the entire threaded bit of the piano wire to get them to fit in! So what I ended up for doing with these for the time being is glued them in place. I will likely go back and form my own piano wire once flight testing is done but for now the glue is holding ~10lbs of applied force fine and I’m not too worried about flying the plane if the flaps give way.
Overall, I like the plane. As anticipated, it is very reminiscent of the Bixler, with a few improvements. The wingspan is awesome and I can tell this will be able to lift a ton of weight. There is enough room in the electronics bay for at least four 2000mAh packs as well as my flight controller and the phone and that’s without any modifications. I will probably be removing the wooden platform that comes with the plane as it just wastes a few cubic inches of space with not much real benefit.
The plane is very tail heavy by default and took the equivalent of 4000mAh of weight right up against the firewall to get within range of the intended CG. This is great news as I will be putting a ton of stuff in here.
Control throw is great, I can get about 45 degree deflection from both ailerons and flaps and somewhere between 30 and 40 on the elevators. With the longer wingspan as much deflection as possible on the ailerons will assist in improving roll rate. Not that this is a huge priority for standard UAV applications.
Something I did not know about the model is it comes with a neat little single landing gear embedded into the bottom of the fuse. There also seems to be foam inserts in the wings for little struts to keep them level on the ground – kind of like the pogo legs found on a U-2, but the struts were not included in the kit. The main gear was pre-built, which is nice, but is not supported by a bearing so has quite a lot of binding if you put any pressure on it. At least it will save some wear and tear on the belly.
There are a few fit & finish problems that I’m not a huge fan of. For one thing, the instructions with the kit say to glue the nose dome on. I want this to be removable so that I can install/remove the smartphone through it. For now I’m taping it, I don’t know what my ultimate solution will be though.
The canopy is secured by 3 big magnets. They are very strong, which is awesome coming from a Bixler, but there is nothing that locates them. This means the whole canopy can slide to one side or another without much force.
The wings also have nothing that holds them in place. It’s a friction fit. This works for now when the plane is new but past experience tells me it will not last. I will probably end up adding a set of washers in each wing and a through-bolt to hold them in place.
Despite these issues I’m optimistic. This is a pretty nice plane at a great price. It looks like it will fit the bill.