Multiplex Shark 15e EPP (Rx-R) Review
Review by Gunnar Hovmark, Staff Contributor
Spektrum DX6 transmitter
Spektrum AR400 receiver
Tiger 900mAh battery, three cells, weight 79 grams
Deans connector and a little extra wire for the ESC
Multiplex float kit for the Shark
- Convenient size
- Quick and easy assembly
- Easy to fly (if you don’t do stupid things with the rudder during takeoff, see ”Flying”)
- Aileron kit and various landing gear kits available
Needs calm weather, waves should not be much bigger than I show in the picture here
This is my very first seaplane. To me it was an excellent introduction to seaplane flying, and it will be fun for a long time to come, especially when I add ailerons. I expect it to also work very well on snow.
I got the receiver ready version of the Shark. It comes with elevator and rudder servos , motor and ESC. I installed receiver and battery, and I’ll probably add aileron servos soon. The ESC comes with a Multiplex battery connector, and the battery wires on the ESC are too short if you ask me. All my batteries and chargers have Deans connectors, so I replaced the connector on the ESC and made the battery wires some 20 mm longer.
The wing comes in two parts that are joined with a spar in the middle. I added a few strips of adhesive tape to keep the halves really tight together. The wing is held to the fuselage with one screw. It’s tempting to tighten it very hard, but remember that it’s easy to damage the threads on a nylon screw. I learned the hard way to be a bit careful when I tighten it. To get a tight and snug fit between wing and fuselage I added strips of PVC tape over the upper gaps between wing and fuselage.
Another thing I learned the hard way is to not put any electronics on the fuselage floor. There are several openings where splashes of water can find their way into the fuselage, so it’s inevitable that things placed on the fuselage floor get wet. My ESC stopped working almost immediately, but after I dried it and instead fastened it on the fuselage wall it’s been working perfectly.
The propeller is an ordinary clockwise-turning type. Since it’s a pusher plane the motor has to run backwards. That means that a good splash of water into the propeller can make the propeller unscrew itself and fall off. So far I’ve secured the spinner nut with blue Loctite, but I’ll probably get a pusher propeller and make the motor run the right way.
The float has to be purchased separately and is very easy to fasten to the fuselage. It’s also very easy to remove if you want to use a skid or an ordinary landing gear instead. The CG position ends up a little forward of the recommended position with my battery.
Total weight with battery and float is 590 grams.
Taxi, takeoff and landing on water was entirely new to me, and it takes a little while to figure out. You definitely need a way to retrieve the plane when something goes wrong. Have a boat available, be ready to swim, or find a pond that’s so small that the plane will quickly drift to the shore.
If the Shark dips a wing in the water it’s usually enough to just throttle back and wait till it straightens up again. In some cases you have to try to turn it into the wind before you throttle back.
Takeoff should always be made straight into the wind so you can keep the rudder straight during the takeoff run. If you have a large amount of rudder applied when the plane leaves the water you will most likely ditch. I did once. Choose calm weather for your first flights. The Shark is a small plane and is not happy with big waves. I have also tried flying the Shark with float off grass, and that works surprisingly well. I expect it to be excellent on snow.
This is a very good introduction to seaplane flying, and I expect it to be even better when I’ve added ailerons and a pusher propeller. The video below is not mine, but it matched pretty closely what you might expect on your first few flights. There are plenty more videos if you search on youtube.
After a couple of months of nice flights off water and snow (and grass even), I decided to add ailerons. I didn't buy the kit from Multiplex, since I already had suitable servos, wires, pushrods and control horns in my scrap box. Cutting out the ailerons and installing everything was very easy, but the result was disappointing. Apparently the ailerons are too small and too far away from the wing tips. It's impossible to make aileron rolls, and I always have to use plenty of rudder to make a decent turn. The conclusion is that I don't recommmend this modification. An interesting experiment would be to make the ailerons go all the way out to the wing tips. Maybe I'll try that.