MPX Glider

Heron bottom - detailHeron top - detailand new looks for the season 2020Hero look - detail

The Multiplex Heron is a high-performance electric glider with its efficiently designed t-tail, four-flap wing and streamlined fuselage bring precision to a broad spectrum of flying. Whether you enjoy lofty thermal soaring, high-speed aerial adventure, or spirited aerobatics, the Heron delivers the flying experience you crave. Its four-flap wing is equipped with an innovative CFRP/Aluminum tubular spar technology for extreme rigidity and stabilization, setting an entirely new standard for the 2.4-meter wingspan class. The glider has ultra-efficient brushless motor, servos, servo extensions. Designed of resilient Elapor® foam with a folding propeller, detachable wings, and tail wing for easy transport and stylishly designed cockpit with a clear canopy.
7 Control Functions: 2 Aileron, 2 Flaps, 1 Motor, 1 Elevator, 1 Rudder

Modifications

Used Oracover ironing film on top of the foam to change the look of this model. Improved the smoothness of the wing edges and surfaces. Installed a Spektrum 9 Ch with AS3X gyro technology RX (3-gyro rate mode implemented) and voltage telemetry with voice alarm on the TX. Modified the canopy to contain the Spektrum Telemetry Vario and Altitude meter (voice and sound status in TX), Airspeed meter, Battery Voltage, Receiver Voltage, and Antenna performance (A, B, L, Lost frames, and Holds) for data logging in the TX.  Configured 5 flight modes and 3 extra switchable mixes (Due to the software limitations of the AS3X receiver I had to use the Flaperon setting in the Receiver and 10 extra mixes in de Transmitter). A Take Off Mode (elevator a bit up), a Landing Mode (split throttle >50% a motor curve with Elevator compensation, <50% a Crow -Butterfly- setup with Elevator compensation), a Cruise Mode (with main trim settings) a Thermal Mode (the 4 flap surfaces a bit down -camber- and a relative Elevation trim), a Speed Mode (the 4 wing Surfaces a bit up -Reflex- and relative Elevation trim) and extra mixes for Full Span Ailerons (Aileron to flap mix), an Aileron to Rudder mix for more turn Coordination (easy to overrule manually) and Snap Flaps (some Elevator to Flap mix in Thermal mode).

Aircraft Characteristics after Modifications

Wing Span: 2.4 m
Length: 1.1 m
Flight Weight: 1.4 kg
Wing Aera: 41 dm2
Wing Loading: 37 gr/dm2
Wing Cube Loading: WCL 5.3
Power: 3S 1350 mAh
Motor: 3516 KV850 Outrunner
Propeller: 1x 12x6 2-blade folding
Stall Speed: 9 km/u
Sound Pressure: <50 dB(A)/7m

Videos

See also the screenshots of the AS3X receiver setup and photos of the DX9 transmitter setup with 10 mixes at the bottom of this pages in Photos.

Performance

MPX Glider Polar - detailMPX Glider Thermal - detail

More information:

RC Soaring Digest
Understanding Thermal Soaring Sailplanes

Mod:

New season, new looks. Modified by ironing (at low temperature) with transparent fluo red Oracover film.

heron new details

Photos

Led Lights – Improve the In Air Visibility

 Concepts, Electronica, Plane, Visualisation Aerial Concepts Belgium, Patric DietvorstAS3X, Fun Cub, Mutiplex, Spektrum

Fun Cub Led Strips - detail

In daylight, you can improve the visibility of an aircraft by using different colors or patterns on top of the wing versus the bottom of the wing. But when sunlight is limited in the morning, in the evening, when it is heavy clouded or there is some fog all colors faint and become gray or black.

Because the battery for the Fun Cub is 3S you can use the balancer connector to get approximately 12 Volts. led strips are available in multiple colors.  I have used short strips with 6 Led green, red, and white to create navigation lights left, right, and in for of the wings. The cables are hidden in the wing with a small cut in the foam and can follow the main spar. Central you can use some simple connectors so you can keep the wings removable. You can cover the electrical wiring with a transparent white tape.

Finally, you have to protect electrical connections and the led strips against humidity. I have used a transparent shrinking tube and used a plastic coating spray from Kontakt Chemie to cover the PCB components.

Fun Cub – Modify the Location of a Flap Servo

 Concepts, Mechanical, Plane Aerial Concepts Belgium, Patric Dietvorst, AS3X, Fun Cub, Multiplex, Spektrum

Fun Cub Flap Servo - detail

Standard the flap servos are mounted identically at the left and right-wing. If you would like to use one flap channel and a split cable you can replace the servo with a reverse servo or and an electronic reverser in the cable, but there is a simpler solution. You can mechanically change the location of the servo, making room by cutting away some foam. The old location you can be filled with some Elapor spare foam.

COG – A good Centre of Gravity

 Concepts, Plane  Aerial Concepts Belgium,  Patric Dietvorst, AS3X, Fun Cub, Multiplex, Spektrum

Fun Cub CoG - detail

Like any other aircraft, the FunCub must be balanced at a particular point in order to achieve stable flying characteristics. The Centre of Gravity (CG) should be at the position 80 mm aft of the root leading edge, i.e. at the fuselage sides. This is correct, but in fig 30 in the manual, the order of the electronic components is not optimal to achieve this CG.

A better order of the electronic is as follows: From propeller/motor; first the ESC motor controller, than the receiver (RX), and most to the back the battery (3S 2200 mAh). With my battery and this plane, the battery had to be put completely to the back above the air ventilation opening on the bottom of the plane. I have put two horizontal carbon rods so the battery can not move vertically. A piece of Velcro keeps the battery horizontally fixed during flight.

I have glued two small pieces of sanding paper (20mm x 10mm) at the bottom of the plane at centers of gravity about 30cm apart. This makes it easy to put your finger at the Centre of Gravity with sufficient grip to balance the ready to fly this airplane (battery mounted)..

Oracover – Ironing Film on Foam

 Concepts, Plane, Visualisation Aerial Concepts Belgium, Patric Dietvorst, AS3X, Fun Cub, Multiplex, Spektrum

Fun Cub Look - detail

Changed the look of this plane with Oracover ironing film on top of the foam. Cut more than a hundred separate squares 30×30 mm of Oracover film. This film gets sticky without shrinking at a temperature of 70-100 °C. Do not overdo it because the foam can expand a little under the film if you heat too long.

Landing Gear – Modifications for hard Landings

 Concepts, Mechanical, Plane Aerial Concepts Belgium, Patric Dietvorst, AS3X, Fun Cub, Multiplex, Spektrum

Fun Cub Landing Gear - detail

Bent two same hooks in 2 mm copper wire for the wheel-side and two other hooks in 2 mm copper wire for the fuselage-side. Grind (with Dremel or sandpaper) the locations where the hooks should be connected to the 3mm tempered landing gear rod intensively. This is important to make good soldering between hook and landing-gear. If you like you can strengthen the connection by winding some thin copper wiring before soldering.

Use 2×2 elastic bands the reinforce the landing gear. Remove the bands if you are nog using the airplane, so the elastic bands last longer.

MPX Fun Cub

Fun Cub front - detail
Fun Cub back - detail

Started flying again with RC planes (after some 20 years) with the Multiplex Fun Cub. One of the first great things about this plane is it’s 55 inch size (1.4m). The wings come off and on in about 2 or 3 minutes.  Simply plug in your servo leads, and screw in the two nylon screws and you’re ready to go.  The plane is very versatile and perfect for just about any field. It takes off in a few feet. Landings are easy with or without using the flaps.

Mods

Changed the look of this plane with Oracover ironing film on top of the foam. Cut more than a hundred separate squares of Oracover film. Add extra suspension on the Landing gear. Relocated a Flap Servo to save an RC channel. Lights to fly in the evenings or with some fog. Installed Spektrum airspeed, voltage, and flight power telemetry. Installed Spektrum 9ch with AS3X technology RX.

Test aircraft

This aircraft is in service since 2016 and flew the most flying hours of all my airplanes. I use this plane now to test new setups, flying modes, and electronics. In 2020 I have tested the new spectrum receiver AR6610T together with the HobbyEagle A3 Pro and the A3super 3, and specific flying-modes to takeoff, cruise, and landing.

Aircraft Characteristics after Modifications

Wing Span: 1.4 m
Length: 1.1 m
Flight Weight: 1.3 kg
Wing Aera: 30 dm2
Wing Loading: 43 gr/dm2
Wing Cube Loading: WCL 6,0
Power: 3S 2200 mAh
Motor: 3516 KV840 Outrunner
Propeller: 1x 13×4 2-blade
Stall Speed: 27 km/u
Sound Pressure: <50 dB(A)/7m

Links

Fun Cub – A good Center of Gravity
Fun Cub – Improve the In Air Visibility
Fun Cub – Ironing Film for a Better Look
Fun Cub – Reinforce the Landing Gear

Videos

Photos