Fox. 2300mm. The MDM-1 Fox is a 14-meter aerobatic glider that made its PNP FMS. Excellent value... great performing glider.

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RC FLY RC Review BY ANDREW GRIFFITH andyg@flyrc.com Excellent value.

happened to win the World Championship in its first outing in 1993.

The FMS 2300mm Fox PNP is an EPO-molded foam kit that arrives with most of the assembly completed for you and needs only a fourchannel radio system, a 1300mAh battery and an hour or so of assembly

Looking over the Fox, the scale-looking flame graphics and tail number are already applied and the entire cockpit is a snap-lock hatch to access the receiver and battery compartment.

The wings seat firmly into pockets in the side of the fuselage and the wing rod appears sturdy enough to take the aerobatics that the manufacturer claims the model is capable of.

1 RC FLY RC Review BY ANDREW GRIFFITH Excellent value... great performing glider FMS 2300mm Fox PNP The MDM-1 Fox is a 14-meter aerobatic glider that made its debut at the World Aerobatic Glider Championships in Venlo, Netherlands and oh yeah, it just happened to win the World Championship in its first outing in The Fox is a two seat composite airframe with fixed landing gear that is manufactured in Poland by Marganski & Myslowski Aviation Works. The Fox is fully aerobatic and rated for speeds up to 175 mph. The FMS 2300mm Fox PNP is an EPO-molded foam kit that arrives with most of the assembly completed for you and needs only a fourchannel radio system, a 1300mAh battery and an hour or so of assembly time to get in the air. Looking over the Fox, the scale-looking flame graphics and tail number are already applied and the entire cockpit is a snap-lock hatch to access the receiver and battery compartment. Speaking of the cockpit, not many models in this price range feature a cockpit with a nicely painted pilot figure and detailed instrument panel. The wings seat firmly into pockets in the side of the fuselage and the wing rod appears sturdy enough to take the aerobatics that the manufacturer claims the model is capable of. The wing has a slightly under-cambered airfoil and if the Fox comes out at the advertised weight it should be capable of thermal or light to moderate wind slope flying. 68 Fly RC MAGAZINE ASSEMBLY TIPS The PNP version arrives with the electric motor, speed controller and four servos already installed. You have to provide your own receiver and battery. The speed controller comes equipped with a standard T-style Deans plug and a BEC lead to power the receiver and servos. There are two manuals included; one covers the assembly of the glider and the other covers the programming and operation of the installed speed 35 amp speed controller. The manual spends several pages on battery safety and other warnings but only one page of diagrams showing the assembly steps. The first step is to assemble the elevator and horizontal stabilizer. The carbon reinforcements go on the bottom side of the stab. When the elevator control horn is installed and connected to the pushrod, it rubs in the channel that is cut in the rear of the fuselage and binds. I had to remove the assembly and using a Dremel tool with a ball shaped cutting bit, cut a deeper and wider channel so that the elevator pushrod and control horn had adequate clearance. Once that was complete, the rudder was hitting the top of the horizontal stabilizer. A few passes with medium grit sand paper on the bottom of the rudder had everything moving freely. It takes just a few minutes to install the remaining control horns and pushrods. I powered up and bound the AR7010 receiver with a spare four-cell receiver pack so I could center the servos. The 7010 was what I had handy, the Fox includes an aileron Y-harness PHOTOS BY ANDREW GRIFFITH

PARK PNP FLYER ELECTRIC WARBIRD GLIDER ARF Author s Opinion The instructions leave something to be desired and there are a few extra things that need to be done during the build process.

Flying the Fox was fun and while not a rocket, the included power system is quite capable. The light weight and under-camber airfoil gives the Fox good glide performance, especially in light air.

NEED TO KNOW MANUFACTURER: FMS DISTRIBUTOR: Diamond Hobby TYPE: PNP electric powered glider FOR: Sport pilots PRICE: $189.

2 PARK PNP FLYER ELECTRIC WARBIRD GLIDER ARF Author s Opinion The instructions leave something to be desired and there are a few extra things that need to be done during the build process. Those small issues aside, assembly is quick and the finished product is a good looking representation of the full-scale Fox glider. Flying the Fox was fun and while not a rocket, the included power system is quite capable. The light weight and under-camber airfoil gives the Fox good glide performance, especially in light air. Tip the nose down and the Fox will perform any of the aerobatics the full-scale glider is capable of. NEED TO KNOW MANUFACTURER: FMS DISTRIBUTOR: Diamond Hobby TYPE: PNP electric powered glider FOR: Sport pilots PRICE: $ MINIMUM FLYING AREA: RC club field or large park NEEDED TO COMPLETE: Requires a four channel radio system and 3S 1300mAh LiPo battery The canopy allows easy battery access, here the Thunder Power 1350mAh battery allowed the model to balance perfectly without adding any weight and can easily be flown with a simple four-channel radio system. With the extra channels handy, I ran individual aileron channels so I could tinker with aileron differential if the Fox appeared to need it. Once the tail is done, it was just a matter of mounting a receiver, running the servo wires to it and plugging in the wings. I noted while building the wing that the long and thin ailerons seemed quite stiff. With the servos hooked up, the ailerons moved well near the servo but twisted quite a bit so that the outboard portion of the aileron was barely moving. I removed the linkages and flexed the hinge line as well as I could but I never did get the ailerons moving completely freely. If flight testing shows that I need more control authority, I ll cut the ailerons free and hinge them with Blenderm tape. When installing the wings there are four phillips head screws embedded in the wing that need to be loosened before inserting the wing joiner tube. The joiner rod slides into a plastic tube and the screws tighten clamps that hold everything together. I decided that for ease of field assembly, I would leave the joiner rod installed in one wing and only loosen the two clamps on the opposite wing to remove the wings for transportation. I installed a Thunder Power 3S 1350mAh battery and ran some power tests with my Power Log 6S ` Key Features > The fuselage and wings are nicely molded out of damage resistant EPO foam. > Factory installed motor with 12 inch folding prop is pre-wired to a 35 amp speed controller. > The removable cockpit features an instrument panel and painted pilot figure. > The easily removable wings seat snugly into pockets molded in to the fuselage and feature a sturdy wing tube and embedded carbon rod reinforcements. > The markings have a two color airbrush-feathered look and are nicely applied at the factory. Pros > Power system and folding prop are installed and the components appear well matched > Attractive looking model which includes a cockpit and a nicely painted pilot figure > Large removable snap-lock-style hatch gives easy access to battery and receiver compartment Cons > Though there isn t a lot left to do, the instructions are not very detailed > The model required some modification to get the elevator installed and operating correctly Fly RC JANUARY

FMS 2300MM FOX PNP IN THE AIR With the nose pointed into the wind I advanced the power and gave the Fox a nice brisk level toss.

Full power climb-out is about 45 degrees and while not a rocket the Fox climbs with authority.

The ailerons, as I suspected, were a little sluggish, as was the rudder. The elevator was perfect.

The Fox glides for a very long time and long flat landing approaches are needed.

3 FMS 2300MM FOX PNP IN THE AIR With the nose pointed into the wind I advanced the power and gave the Fox a nice brisk level toss. The nose pitches up and requires down elevator pressure at anything over half power to maintain a stable climb rate. Full power climb-out is about 45 degrees and while not a rocket the Fox climbs with authority. Not wanting to get too far out on a test flight I chopped the power as the model reached about 200 feet and tested out the controls. The ailerons, as I suspected, were a little sluggish, as was the rudder. The elevator was perfect. After a few photo passes, I brought the Fox around for its first landing approach, then it s second and finally on the third, very long approach, I managed to get it on the runway. The Fox glides for a very long time and long flat landing approaches are needed. While on the ground, I raised the end points on the ailerons and the rudder until I had as much throw as I could get without binding. I put in a mix to add down elevator as throttle was added starting at 10 percent down elevator at full throttle. I also created a switchable mix to coordinate the rudder with ailerons. With these programming tweaks in place I headed out for another flight. This time the launch required just a hair down elevator to maintain a safe climb angle and the final mix to maintain a perfect launch, without touching the elevator, was 13 percent. The aileron and rudder response was improved as well. The Fox has a wide performance envelope. With the nose pointed down it picks up speed quickly and loops well even with the power off. Rolls are a slave to the marginal ailerons so while they are possible, they are neither crisp nor particularly fast. Inverted flight requires a fair bit of down elevator. I m sure this is due to the airfoil, but the Fox will fly inverted, it just takes a little work. The rudder is effective and wing-overs and stall turns look pretty good. Wing flex with 92-inch foam wings could be a problem but the Fox appears to be adequately reinforced and while some wing flex is visible in high-g maneuvers, I saw nothing that made me think that wing failure was imminent. I also noticed no flutter in the control surfaces during high speed dives or high-g pull-outs. Usually a glider will thermal or do aerobatics well but not often will it do both, especially without flaps for camber control. Launching with a 30 to 45 second motor run will take the Fox to a few hundred feet. Chop the throttle and the Fox, due in part to its under-cambered wing and light weight, will circle upwards in the lightest lift. It will also circle tightly without losing altitude so it will work lift down low before the developing thermal spreads out. A word of warning though, lacking both flaps and spoilers, the Fox has a hard time breaking free from lift and once required me to fly it down several hundred feet inverted or risk it disappearing. Even adorned with bright orange markings, the white fuselage and wings can make seeing the Fox at higher altitudes a challenge. This is especially true on cloudy days with a white or gray background. Consider adding some colored panels to the bottom of the wings. Landings present the same challenge as breaking lift. Displaying an excellent L/D ratio and no spoilers, the Fox will glide a long way before coming to rest on its two wheels. I found the best way to make our main runway consistently was to cross control the Fox into a side slip once clear of the fence. This allows you to dump altitude quickly without building up airspeed. Some glider purists may not like electric gliders, but one of the nicest things about flying a powered glider is the ability to power up and go around. SPECS WINGSPAN: 91.5 in. WING AREA: 559 sq. in. FLYING WEIGHT: 2 lb., 4 oz. WING LOADING: 9.2 oz./sq. ft. CUBE LOADING: 4.7 LENGTH: 52 in. RADIO: Flown with a Spektrum DX18QQ transmitter and Spektrum AR7010 receiver MOTOR: Brushless Kv (included) BATTERY: Thunder Power 1300mAh 25C 3S LiPo PROPELLER/SPINNER: 12x6 folding prop and spinner (included) MAX RPM: 7,000 POWER CONSUMPTION: 23 Amps 255w DURATION: Eight minutes motor run time We Used RADIO Spektrum DX18QQ, SPM18800 RECEIVER Spektrum AR7010 DSMX, SPMAR7010 BATTERY Thunder Power 1350mAh 3S 25C, TP1350-3SPP25 watt meter from Progressive RC. At full throttle with a fully charged battery, the power system draws 23 amps and a bit over 250 watts, putting the power loading at a shade over 100 watts per pound. No 3D but it should have plenty of performance for powered gliding. I set the balance point at 40mm from the leading edge as indicated in the manual. I also calibrated the throttle end points and made sure the ESC was set to engage the prop brake. The only radio programming that I did beyond setting up the servos was to setup a throttle kill on a toggle switch. If your radio is capable of it, a throttle kill is a very nice safety feature to have. THE LAST WORD The Fox is a lot of fun to fly. It would be a good transition model for someone looking for more spirited performance than a floater-style plane like the Radian, while retaining the ability to thermal or slope soar. The kit has a few minor issues, but considering that it can be completed in an hour or less, even fixing the minor issues, and that it doesn t need a fancy radio, the Fox is an excellent value for the price. We always review models as they arrive unless there s a serious issue that requires modification so I never re-hinged the ailerons, but I believe that doing so will make a good flying model perform even better. 70 Fly RC MAGAZINE CONTACTS DIAMOND HOBBY diamondhobby.com, (850) PROGRESSIVE RC progressiverc.com, (443) SPEKTRUM RC spektrumrc.com, (217) THUNDER POWER RC thunderpowerrc.com, (702) For more information, please see our source guide on page 105.

4 PARK FLYER WARBIRD ARF Fly RC FEBRUARY

5 E-FLITE APPRENTICE S

Please read all instructions carefully before assembly and flight!

Please read all instructions carefully before assembly and flight! Thank you for purchasing the Mig-15. This model is designed for the intermediate to advanced flyer. The model is receiver ready and includes