I just assembled my 4th Acuity. My first one was a 62″ that I bought when I started flying pattern. I soon bought a 2m Acuity and flew it and eventually sold my 62″ version. A few years later, after lightly crashing the original due to a faulty cheapo servo cable, I bought another 2m Acuity. They really are hard to beat, either version, for the money. I’ve had much more expensive planes, but the Acuity stands its ground when compared.
After deciding last year not to travel for pattern contests any longer, I scaled things down so I don’t have to have to accommodate 2m planes. So I sold my 2m planes and bought another 62″ Acuity.
This Acuity is far and away the best quality I’ve seen on one yet. The others were all fine, but this one was perfect. I haven’t purchased many ARF airframes that didn’t need at least something to make the setup measurements perfect. No need for blades, shims or sanding on this one.
The canopy attachment did require work to use without the supplied thumb screws. I added a small piece of light ply, some fiberglass cloth and some Epoxy and was able to create a nest for the spring loaded canopy latch attached to the fuse. I basically filled n the area between the rear screw for the Tcan and the rear edge of the canopy with glass cloth and epoxy, let it set then drilled it out and coated it with thick CA and accelerator. I sanded inside the hole and now it’s a hard area for the canopy latch to hold on to. In the past, I have just used the thumbscrews to hold on the canopy. I am determined on this one to use only the top latch. We’ll see…
I already had the AJ motor used for 5s on this plane. I bought it for a project that I have yet to complete, so I reappropriated it 😉 It is the AJ4025-14P 485kv. It appears to match perfectly with a Hacker A50 12s when compared on eCalc. The Hacker is rated at 480kv is the only difference. So this plane will run on 5s power. It will help with weight for sure.
My first 62″ Acuity was powered by 6s with a Hacker A50 16s, which is the 6s version. It had boatloads of power and was always a little nose heavy, even when I moved the rudder servo to the aft position. You might think that running the same plane on the same prop and getting more thrust on 5s than on 6s isn’t possible. Look at the two images below. They are eCalc profiles of this plane with the 5s motor and the 6s motor. You give up a little flight time, and maybe tax the motor just a little more on 5s, but overall, the 5s setup is more efficient. It generates about 10% more static thrust on 5s.
My 6s Acuity was 3600g all up. This 5s version is 3060.
EDIT:
Before even flying this plane, I was looking for a motor for another plane and came across a Scorpion SII 4025 440Kv motor. This motor weighs less than the AJ motor I planned to use and gives this Acuity all the power it would ever need. So I installed the Scorpion motor. It bolted right up to the pre-drilled holes on the plane. It added 1.8mm to the gap between my spinner backplate and cowl, but I had it fit very closely before, so I’m not going to re-drill my mounting holes on the cowl. I’m good with a 2mm or less gap. I have included an eCalc profile below for the plane with this motor. It has tone of power and hardly taxes the motor at all. I might have just found a new favorite motor.
SECOND EDIT:
The Scorpion motor mentioned above is a total bad ass of a motor, but it is just too much for this plane. I would never use the top half of the throttle range, so I took it off and will use it on the new upcoming project, a Super Chipmunk in the Art Scholl scheme. I went back to the AJ 4025-14P on 5s for the Acuity. It gives me all the power I need and we lose almost 5 ounces going from 6s to 5s.
After a few flights, this 62″ Acuity flies beautifully. These planes really do offer great value.
I used MKS HV69 servos for all surfaces on this plane. These are great servos for a plane this size. They center very well and perform very well when running on straight 2s lipo power. I use a 1000mAh 2s Lipo for the radio and can fly all day without needing a charge on the system battery.
The HV69 requires a little bit of changes in the servo bays. I add a small piece of 1/8″ ply to extend the area where the servo is screwed down. I make lite ply covers and fit the HV69 in them. It requires just a little work, but gives you lightweight, powerful, fast servos that don’t require a voltage regulator. The servos are very stable because the lite ply cover holds them in place when screwed down.
I haven’t flown this plane yet. I plan to in about a week.