Staufenbiel Competition Epsilon V2 3,5m Review

Review by Gunnar Hovmark, Staff Contributor

Equipment Used:

Motor: HIMAX 3528 (pre-installed)

Receiver: Spektrum AR6210 6 Channel

Transmitter: Spektrum DX6i

Aileron servos: Hitec HS-125MG

Flap servos: EMax ES09A

Rudder and elevator servos: EMax ES 9258

ESC: HobbyWing Flyfun 60 A

Extra servo leads:

2*200 mm for flaps inside fuselage

1*200 mm ”Y” connector for ailerons inside fuselage

2* 300 mm for flaps in wing

2* 900 mm for ailerons in wing

Balancing weights: Zinc, self-adhesive, a total of 165 grams in the nose.

Battery: Gravity 3s, 4000 mAh, weight 340 grams.


Some technical data:

Wing span: 3500 mm

Length: 1510 mm

Weight, fully assembled, with battery: 3.6 kilograms


Very high L/D.

Low sink rate.

Excellent finish.

Robust construction. (I’ve already made one REALLY bad landing, I had to replace the propeller and glue a few things back in place, but there’s no trace of that mishap that can be seen now.)

Easy to assemble.

Very nice to fly, once you get the hang of making coordinated turns with rudder and ailerons.


The canopy may lose its shape after a while, which means that the folded propeller may get stuck under the edge of the canopy. It’s easy to bend the canopy back into shape by heating it with a hair dryer though.


The control horns are strong, but not elastic. If you try to force the control rods into them they may crack.


The assembly instructions are in German only, and with only a few pictures. If you don’t read German yourself it might be wise to find somebody who does, even though most of the assembly work comes quite natural if you’ve assembled ARF planes before.


The servo covers for the wing servos are not cut to fit, and it’s very easy to make mistakes when you cut them yourself. Take measurements carefully before you start


The 3.5 m Epsilon is sold as an ”F5J trainer”, i.e. it’s a plane for newcomers to the F5J competition class and others that want a high performance motor glider at a considerably lower cost than the top-of-the-line F5J ships.

The fuselage is made mainly of carbon fiber, but with fiberglass ”windows” for a receiver and satellite receiver. The wing has a foam core, covered with balsa and Oracover. The horizontal tail is all moving.


The plane comes almost completely assembled. What’s left to do is to install the control horns, join the six wing pieces together (each half is consists of three pieces), install the ESC and the mounting plate for the battery and servos in the fuselage, install all radio equipment, glue the stabilator and the rudder hinges in place, and make sure the C.G. position is right. Also, the trickiest part of the assembly is to drill the holes in the wing root for the fasteners that are used to keep the wing halves together. My guess is that the factory simply forgot to do that on my plane. I used slow curing epoxy for all the required gluing. The instruction for fastening the battery is a bit vague. I used velcro and also added a bit of spruce in front of the battery to keep it in place, and a bit of plywood on the battery to avoid dents if it should hit the edge of the ”cock-pit”.   The Epsilon is also sold in a ”plug-and-play” version, with servos already installed, and with very clever servo connectors between the wing and fuselage.


The wing halves are held together with a steel spring, using a special tool that comes with the plane. It takes a bit of practice to operate it quickly. The first times you can expect to be fiddling with it for a while.

My own experience with gliders is somewhat limited, having flown only 2 meter planes without ailerons before. Moving directly to the Epsilon was a bit of a challenge for me, but quite feasible. I still need a lot of space for my landings though, this plane just floats and floats. I may have to get a more advanced radio and learn more about mixing if I want to make real precision landings. This looks like a useful link:


With the DX6i, the mixing possibilities seem limited to having four different flap positions, and no mixing of the ailerons.

To sum this up, I’m quite pleased with this plane, and I can strongly recommend it for those that want a high performance glider for sport flying, and I believe it's also a good choice for those that want to try F5J without spending all their life’s savings.


Dealer in Sweden:

Designer and main dealer: