|Flying Weight: 20.2oz as reviewed|
|Motor: 20mm Brushless Inrunner|
|Prop Size: 5x4|
|Battery: 2S 2100mAH Lipo|
|Available From: HobbyKing|
The Dynamo is a traditional built up glider that can be used on the slope, bungee launched or powered with an electric motor. It was designed by Felipe Vadillo and is a 3 channel model with a 1500mm polyhedral wing. It comes pre-built and covered in lightweight film and requires final assembly and electronics installation to get it flight ready. It has provisions for a pure glider setup and includes a tow hook, but I chose to power mine with an electric motor. Let's crack open the box and take a look inside and see what this plane is all about.
When you open the box you'll find all the airframe parts nicely covered and ready for assembly. The wing is in 3 pieces and you'll see the fuselage, tail sections, wing spars, pushrods, hardware and the instruction manual.
HobbyKing sent the electronics needed to complete the build. The 3S lipo in the photo was too small and too high a voltage for the motor so I used a 2S 2200mAh lipo to get the CG right and keep the amps down on the power system. Here's a list of the parts you could purchase to complete your kit.
Final assembly is pretty simple and quick. It takes less than an hour and you'll need some basics like a screwdriver, CA glue and a hobby knife. The manual walks you through the steps and does a good job explaining the process. I started by gluing in the control horns for the rudder and elevator. Make sure you install these on the correct sides of the surface per the manual. Next I glued in the stabilizer mount. You can choose to install it with screws if you like, but I just glued mine in. The tall side should be positioned toward the rear of the fuselage.
Next I installed the horizontal and vertical stabilizers. You'll need to use a hobby knife and carefully remove the covering material where the glue joints will be. I chose to use 5 minute epoxy to glue these on.
Next I installed the servos and control linkages. The pushrod tubes are already installed in the fuselage so you just need to run the wire through and down to the control surfaces. I used the provided hardware to connect the pushrod wires to the control surface horns.
Next I installed the power system. You could choose to install the balsa nose cone to make it a pure glider, but I wanted a powered glider. I needed to drill out the holes in the firewall for the motor attachment screws and then secured it with two screws. Then I installed the folding prop system. The spinner is a little small for the fuse, but it was the closest match I could find. The prop doesn't fold all the way, but should reduce drag some when the power is off.
Next I went to work on the wings. The fit is nice and the instructions let you know that you don't need to glue the outer wing panels in place. They can be taped on and removed for transport if needed. The wing is small enough for me so I decided to glue them on and make it a one piece wing. I used 30 minute epoxy to glue the spars in and to join the panels to the center section. Use some blocks of the same height to prop up the outer panels and ensure the dihedral remains equal while the glue cures.
The last thing to do was to install the receiver, ESC, battery then attach the wing and check for proper CG. I installed the receiver in the servo bay and then attached the wing with the provided screws and washers. The 2S 2200mAh was a perfect fit and the CG was right on the money at 45mm per the manual. I did a quick pre-flight check of all the controls and then waited for a nice day to go the field and fly.
There is no landing gear so the Dynamo is a hand launch model. The fuse is easy to hold and you can launch it with power on or off. It will glide a good distance just from a toss and makes launching super easy. There really is nothing to it.
The Dynamo has a polyhedral wing making it a very stable flyer. Hands off it will self right in the roll axis making it a gentle and enjoyable cruiser. Turns are well coordinated and require just a touch of up elevator to maintain altitude in a turn. With the power on it will pick up some speed and can climb vertically at full throttle with the power system I used. That allows you to climb to soaring altitude quickly and shut the motor off. Power off glide is superb and you can hunt down thermals and stay aloft for as long as there is lift. Flight times at half throttle are 10-15 minutes, but you can stretch that by soaring.
You can perform mild aerobatics, but you'll need to watch the energy and not stress the wings too much. There are some small balsa and fiberglass spars, but they will not hold up to power dives and high G pull outs. You can do loops and it will do a nice barrel roll with full rudder input which you can see in the video below. I even managed to get it to fly inverted and controllable which is rare for a polyhedral wing. There is plenty of power and you can pull into a loop from level flight without having to dive and gain energy.
Getting it on the ground is simple. Just get used to the glide path and bring it in with a slight flair at the end. Make sure the motor is off before touchdown and the plane will slide along the grass slightly on the fuse. The gentle handling and slow flight characteristics make landing the Dynamo easy.
While the Dynamo is a great flyer and easy to handle, I wouldn't recommend it as your first plane. Wooden built up planes are not durable enough to withstand the punishment that first time flyers put on airframes. A foamy with some gyro stabilization is a better choice, but if you have some flight experience the Dynamo is a great choice.
|HobbyKing Dynamo Electric Sailplane (5 min 21 sec)|
The Dynamo is a great looking and great flying sailplane. It's nice that you can build it as a pure glider, or powered and that they give you provisions for a tow hook for bungee launching. The kit quality is very nice and the covering job was fantastic. You can build it in less than an hour and have your choice of removing the wing panels for smaller spaces. The electric power system is great for flatland flying and will yield long flight times. It handles great and will soar and perform mild aerobatics. The only downside is you can't stress the wings too much, but that is typical with planes like this. The price is very affordable and being a wooden plane, it will last for years and years and hold up well to hangar rash.
Nice article & pics - thanks for posting.
I picked one up in the sale a couple of months back for a great price - although haven't done anything with it yet.
Interesting choice of motor & prop ! - actually a very powerful setup, shame there isn't enough clearance to get that prop to fold back - which makes me think an outrunner would be better, but it's a case of finding the right one...