Buds F-86 low pass crop

1/24/2015 - I’ve never owned an electric ducted fan (EDF) airplane. I like to watch turbine models fly because they are fast and the sound is awesome. If money were no object I’d probably own a couple of them. The smell of kerosene takes me back to my days in the Air Force. The problem with turbines is the cost and field requirements. There are some kits out there that are more than capable of grass field operation but you better be good to your retracts and able to manage a short approach over the trees on the north end of the field when the wind commands it.

EDF’s on the other hand are very affordable, but most sound like an electric leave blower. There are a lot of bad kits, poor designs, weak gear and low performance options out there. Taking off from the grass needs good performance and stout landing gear. Some of the better performers use fixed gear to save weight and provide landing gear that can take the bashing a grass take off and landing deals out. There are hand launch and bungie launch-able kits, but they are small and not as cool as something that has retracts and size. I’ve seen plenty of these at the field over the years. Some run up and down the field without achieving take off speed. Others offer very short flight time and require a launcher for the bungy or trade fixed gear for speed.

What I was looking for was a plane that could take off from our field, had retracts and sounded like a turbine. I wanted to get 5 minute flight times and be able to use my existing LiPo batteries to power it. It needed to have reasonable wing loading because I have been known to fly pretty low and tight.

The search was on! Right away it became clear that Freewing seemed to offer the best quality in EDF kits. I started to look for suppliers carrying that brand. After my bad experience with the HK C-47 I wanted somebody that stood by their products with fast support. has developed a good reputation over the years and is a Freewing dealer. Their prices are reasonable and shipping is free on orders over $99.

I started looking at the battery requirements. Since I fly 550 and 700 sized heli’s I have an abundance of 6s 5000mAh packs. My other packs are either 3S or sub 3000mAh 4s.  It quickly became clear that I was going to need to look at a plane with a EDF unit in the 80-90mm range. This narrowed the selection significantly. 

Now the search was focused on the landing gear. Big LiPo’s add mass and retracts on a grass field equal stress on the gear. All the pretty scale jets with tiny nose wheels were quickly dropped from my list. Those wheels were far more likely to dig into the ruts, bumps and clumps on our field. This was confirmed in the reviews I read. The sport jets available with bigger wheels looked good, but had short flight times of around 3.5 minutes caused by the 90mm fans pushing them around. Thats the price of EDF speed. The search moved to scale jets of the '40s '50s and ‘60s. These jets had less intricate landing gear designs and bigger wheels because of the technology of the day. In addition early jets had relatively low power so they usually had more wing area which would slow the plane, but would provide longer flight times.

I read all the reviews on the sellers site and then moved over to RC Groups for the planes I was interested in. It came down to the Freewing ME-262 70mm twin or the Freewing F-86 80mm. Both are popular kits and landing gear is known to be good quality and relatively tough. The ME-262 was more than happy to accept the 6S 5000mAh batteries I have. The F-86 was designed around 6S 3700mAh to 4500mAh batteries. Hummm looks Like I either buy batteries or the ME-262. As I read about the 262 I started seeing some issues with the forward fuselage strength and ESC failures. I looked at how close the engine pods are to the ground and started considering flight time of one 5000mAh battery powering two 70mm fans.

I dug further into the F-86 thread on RCG and discovered that while not designed for it quite a few people had opted to use 5000mAh batteries with very little modification. It really depends on the pack you use since their dimensions vary quite a bit. As I read further it was more and more common. With throttle management people were getting 5 minute flight times which was one of my criteria.  It became clear that both planes would be a pain to assemble the wings to the fuselage at the field because of the short and abundant servo, ESC and throttle leads.  The 262 has a 60” wing span while the F-86 is closer to 48. Clearly another criteria I needed to consider was size and transportability. I could get either in my car, but the ME-262 was going to be tight when you consider I usually take several aircraft to fly and my wife also packs along at least one heli and plane to fly.

I started to do some YouTube research next to see how the two planes appeared to fly and what kind of fields people were using them on. There are also a number of video reviews and unboxings to see what to expect in the way of packing and kit quality. Generally the planes looked great and both were flown off of grass fields. The 262 is pretty fast while the F-86 looked scale in flight.

This is where the scale started leaning heavily in the F-86 favor. The SOUND! While the ME-262 was a twin it still had the normal EDF leaf blower sound generated by its 6 blade fans. The F-86? Its hard to believe but with the combination of 12 blade fan, scale sized nose air intake coupled with a louvered cheater air inlet in the bottom of the fuselage it sounds VERY much like a turbine in flight. The more I heard it the more I was sure this was the plane I would buy. 

With the model decision made for the F-86 I read up on issues people were having with the kit. The biggest issues were main gear tearing out due to insufficient glue holding them and a CG issue. The bigger problem was the nose heavy CG when setup using the instructions 165mm recommendation. People were saying that it took a very long take off run even with flaps to get airborne (beating the poor landing gear to death no doubt) and all the elevator they could give it to rotate for lift off at the end of the long take off run. Some were convinced it was an issue with the incidence in the elevator as people were maxing out the elevator throws and requiring a ton of nose up trim. They had to make fast landings in order to retain enough elevator authority to flare. It turns out the issue was all about an incorrect CG recommendation in the instructions. The Freewing F-86 is happy with a CG point of 190 to 200mm as measured from the lead edge of the wing root. With this CG range the plane lifts off relatively quickly with flaps and has no need for elevator trim or excessive speed on landings.

I ordered the F-86 from for $299 shipped. You can get it as a kit or PNP. Mine was the PNP version. It needs only a receiver and battery pack to fly. I ordered on a Monday morning and the plane was at my door via UPS Thursday afternoon. No box damage was noted and it was double boxed. The packing was extremely good. The planes condition and paint were both excellent. The level of detail in the planes markings and decals is amazing for a foamy! All control surfaces were already connected to their servos.

The only assembly is to glue the aft section to the front section of the fuselage using the glue provided with the kit, screw on the elevator and rudder assemblies with 4 screws, put the two wing halves together with a carbon tube for support and attach the wing to the fuselage with 4 screws. The biggest deal in this is connecting all the servo leads at the tail and wing to fuselage. Take your time doing this as the slack is short in the leads and you don’t want to take it apart to re-accomplish this if you get a wire crossed. It is highly recommended that you check all the servos and gear for proper operation BEFORE starting assembly. This ensures that the servo wires are properly labeled so you don’t get something like a flap moving when you move an aileron. In my case everything was labeled correctly and worked fine. The finished plane looks VERY scale.

Because I was running bigger than normal batteries I had to do a couple of minor modifications to get them to fit under the canopy hatch.  The first thing was relocate the ESC and battery. In order to get the CG to the 190mm point I had to move the ESC from its stock location to the rearmost point under the hatch area. There is a clear plastic cover that can be opened up in this area to permit air going to the fan to help cool the ESC. I cut a hole in the clear plastic and then hot glued the ESC there. Next I had to relieve the cockpit floor in the hatch to the point that it was paper thin in the area under the pilot figure plus cut a hole in the area in front of the pilot figure to make room for the batteries wires to clear. Once I had removed enough foam I reinforced the section I had relieved with thinned 5 minute epoxy. Others have had to do nothing more than move the ESC to get the battery in the right position. It really depends on the battery you are using. I also decided to glue a scrap piece of foam in front of the battery to keep it from shifting in flight. I would normally use velcro for this, but because space over the battery was tight I had to go this route. The kits packing had some pieces that were perfect for the job.

Everything was setup with maximum throws and 30% expo. RCG discussion indicated the plane was not sensitive to a lot of elevator, rudder and aileron. Flaps are 45 deg and 80 deg of throw. Looks like a lot, but this plane likes a lot of throw. One thing I noticed when I powered up the plane on 6S the first time was the left aileron deflected up 1/8” and buzzed when initially powered on. Bumping the sticks caused the buzz to go away and the aileron centered fine afterward. BUT it did this every time the plane was powered up in 6S. Previous experience with the HK C-47 taught me to do a voltage check on the BEC before connecting up any other components. In this case the voltage was under 5.8v so I didn’t think that was going to be the cause of the issue. The aileron servo issue came back to haunt me later though.I am using an Orange 8 channel Futaba compatible receiver and did a good range check to make sure everything was good before take off. 

Since I wanted to get a good idea of flight time I set my timer for 4 minutes to be conservative and rather than taxi to take off position I carried the plane there to ensure I would have plenty of juice for what I expected to be a long take off run. I opted to take off without flaps the first time since I had the space needed to make a good run and wanted to feel the plane out at low speeds. Take off was longer than I am used to with scale propeller driven planes, but the plane got up to speed quickly. It did not attempt to lift off on its own and needed a good amount of elevator to rotate. I was conservative on the elevator as I figured rushing it with a large input risked a tip stall with the heavy sweep in the wings. I probably could have lifted off sooner if I had stabbed at the elevator.

Once in the air the only trim needed was some left aileron. No elevator trim was needed. It SOUNDS AWESOME! I cruised around at altitude feeling it out. its not nearly sensitive to drop a wing in low speed turns as I have experienced on pusher prop driven planes with high wing sweep. It does need a good amount of rudder in tight turns. I immediately felt comfortable making low passes. Flaps didnt need any elevator trim. I had dialed the speed back on them so they deployed slowly. Did I mention that it sounds AWESOME? Very very turbine like. Anyway at the 3:30 mark I decided to shoot a landing. No flaps were used and it glided much longer than I thought it would. I also carried some extra speed to make sure I didnt stall it. The 4 minute timer went off just as the landing rollout stopped.

The next flight I took off with flaps. WHAT A DIFFERENCE! The take off run was 2/3 as long as it was without flaps. Climb-out was good, but the drag from the flaps was evident. I pulled up the flaps and gear then proceeded to fly it around like any sport plane. Rolls with full aileron were scale like. Loops from level flight were good, but you needed to be at full throttle before entering them to have enough energy. Landing with flaps was much slower and very predictable. Landing rollout was of course much shorter.

On flight 3 I noted some odd wing wagging as if an aileron was being wiggled. I chocked it up to the wind effecting it since a cross wind had popped up since the first flights.

On flight 4 I didn't see any wing wag. When I landed and after taxing back in noticed that the right main gear was not fully extended. I cycled it several times and it worked fine afterward. Dont know if this will be a repeating issue or not, but it was not an issue on flight 5.

On flight 5 I had a very bad feeling as if I was having radio failure about 1/2 way through the flight. It seemed as though power was down and aileron control was slow. I thought I was going to lose it in the trees for a little while. I dropped the gear, went to half flap and landed. It didn’t seem to have the power to taxi back in. Once back on the bench I discovered that the left aileron servo had failed in flight. It was working prior to take off. I also still had plenty of battery left and the power from the EDF seemed fine. I guess the taxi issue could have been the nose gear stuck in a rut. Anyway the left aileron that I had noted previously as not centering on initial power up was dead. It was not stripped, but could be moved with resistance. 

I sent an email to MotionRC support Sunday afternoon. Monday afternoon they emailed me back saying they were shipping a new servo to me. The servo arrived Thursday of the same week via US mail. I am going to have to do a good check flight and have decided any new planes will get a two hour burn-in period on the bench before fight to catch any servos that are prone to an early death. I will also keep an eye on the EDF power to make sure all is well there.

In summary the Freewing F-86 is a great entry into EDF flying. The plane looks very scale and flies well. It tops out at 80-85mph in flight so as far as EDFs go its on the slower end, but it is much faster than a lot of prop driven sport planes. Anyone able to fly a scale 40” wingspan propeller driven foamy warplane with retracts and flaps successfully should be able to handle this jet. There has not been any other EDF I have heard that sounds as good as this one. It really does sound like a jet. after 4 minutes of flying including taxi out and back I found I was using just 3200 to 3700mAh out of the 5000mAh packs. With throttle management 5 minute flights are possible. The servo failure is a bummer, but I have seen a lot of servo failures on BNF and PNP planes so they do happen pretty much to all kits to some degree. In this case it gave me warning, but I elected to just keep an eye on it. MotionRC support was excellent and I feel confident that I will buy from them again.

[UPDATE 1-28-2015]

The 2nd weekend out with the F-86 I had two more servos fail on one flight. One was a flap and the other was the rudder. The failures were electronic not mechanical.  I decided not to contact MotionRC for replacement servos because I like the plane and will replace them as they fail with Hitec HS-55s. I feel the stock servos are a crap shoot at best. On landing I also noted that both main gear were not fully extended. Cycling the gear they went to full extension and appeared to be locked down. I previously reported that on flight 4 I had this same issue on only the right gear. The plane has not had any hard landings. Time will tell if the gear holds up. With only 6 flights on it so far its questionable.

You can watch the maiden flight below.

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