Konrad
Posting Elsewhere
I’m posting this here after recently seeing the aftermath of a failed maiden. I feel that to have kept this known gross misinformation in the manual concerning aileron throws and balance for over 2 years shows utter contempt by Freewing and/or her agent (MotionRC) for their customer. Should someone get hurt as a result of the misinformation in the manual, it would constitute criminal misconduct.
I’ll start with my initial on line post.
This Delta needs some changes!
I purchased this Freewing Mirage 2000 over two years ago from MotionRC as an ARF kit. Motion RC did not have the Kit Plus option at the time. As with all modern military aircraft the camouflage makes tracking these models very difficult for these 50+ year old eyes! Low visibility gray works!!! On the ground I do like the two tone French camouflage. But as I have to see the model in the air to control it military paint schemes are not appropriate. Luckily there're Mirage 2000s that have been painted in many "Tiger Meet” paint schemes. I’ve chosen to paint mine in the 2004 Tiger meet scheme. The bright yellow, orange and green will make the model pop in the sky, well if one is looking at the top side of the model.
Much to my horror I’ve found the Freewing does not have, nor have they found a paint processes that allows their paint to adhere to the base material of the model very well. This is not only a problem for Freewing but is an issue for all manufactures of EPO foam models. I have yet to find a masking material that will not lift off the OEM applied paint! The best I’ve come up with is to use “Frog tape for delicate surfaces”. And then to lift off the mask (Frog tape for delicate surfaces) I have to warm the mask with a hair dryer, warm only don’t get it hot or the EPO beads will expand.
With all the masking and repainting issues I was having I was shocked to find that I had spent over 12 man hours just to get some color on the model. As this is a foamy I told myself there is no point trying to make a silk purse out of a sow’s ear. It will never look great up close, that isn’t the point of a foam model. So I assembled the model to fly even with some of the tiger strips missing.
As I mentioned earlier I’m using an ARF kit as my starting point, I'm using the Freewing inrunner fan housing with Neu1410/2Y/SE 1850Kv motor and Jet Fan rotor. I’m also using Freewing branded servos. Batteries are Revolectrix 435 series 4600 mAh at 620 grams. Flight testing has reveled some major control issues, predominately with the aileron roll rate. As spec’d and as set up in the instruction manual, the full span control surfaces offer far too much aileron deflection for any hope of controlled flight. Limiting the servo motion at the transmitter results in a large loss of servo resolution and power. This is NOT desirable under any condition. And is a greater concern with the recommended small 9 gram economy type servos than come with this model, as these are NOT of the highest quality nor are they digital (to be clear, they are adequate for a foamy).
With the servos set up to give the desired elevator response one needs to turn down the aileron command input by over half (48%) that of the elevator movement. This is a very bad condition if one hopes to maintain any kind of servo resolution for aileron control.
The manual failed to mention that with delta wings there needs to be much more down elevator movement than up elevator movement. This is because the elevator is reflexed (airfoil) for a positive pitch moment (stability). To fly level inverted the elevator needs to move a great deal more in the “downward” direction to effect the needed reflex in the inverted position. For a balanced feel between up and down on the elevator stick I had to add 150% more to the servo's downward end points in the transmitter menu. Otherwise I had to hold over 3/4 forward elevator stick just to maintain inverted flight.
In my case I moved the push rod one hole closer to the servo axis, for a servo arm length of approximately 7 mm. This still allowed a bit too much up elevator movement. I had to electrical limit the high rate elevator, not the best solution. I plan to slant the servo arms rearward to set up the much needed elevator differential (mechanically). Unfortunately this will result is reversed aileron differential. I will have to address this electronically within the transmitter programing. The proper solution would be to split the wing trailing edge into dedicated surfaces (elevator and aileron). I don’t know why Freewing didn’t go this way. The cost of 2 servos would only have added to the manufacturing cost by about $5 usd. (The 80mm Freewing F-5 has twice as many servos, so servo cost isn’t the issue)
Flight performance is exceptional for a thick winged foamy at 6,000 feet altitude. With the above mentioned power set up the model was drawing 92-90 amps. (My Freewing F-5 with the upgraded Freewing inrunner is drawing about 84 amps [73 amps inflight]). In straight line speed the Mirage 2000 is the fastest of the 80mm Freewing jets. But with the thick foam wing the speed is still in the sedate 100 plus MPH range. I did notice some instability in roll as the aircraft would rock about 2 degrees at a rate of about 4 to 5 oscillations a second. This would be a perfect place for a gyro but with the low resolution analog servos recommended and the poor mechanics of the linkage the true benefit of the gyro might not be realized.
I find that the best balance point is 3mm ahead of the rear most recommend. (This point is found when all three wheels lift off the ground at the same time, none of this upside down desensitize (dampening) stuff). Delta wings are more limited in range for proper CofG. The range given in the Freewing manual is far too wide! It needs to be cut in half! I have found that best CofG to be at 523mm froward from the aft end of the nozzle. With a delta wing it is best to be a bit on the tail heavy side. With a nose heavy delta winged ship, landing speeds are just too high!
Even balance towards the aft end of the Freewing's CofG range I have to cary 1mm of up trim (measured at the widest part of the control surface and against the aft fuselage fairing). From the same point my control surface movement is as follows:
16mm up Elevator
22mm down Elevator
9mm up Aileron
8mm down Aileron
Rudder all I can get. With the low rate set at 40% to control the take off roll and to dampen the high speed taxiing.
Along with the Delta wing mix I have resorted to using one more mix. There is a strong downward pitching motion with the gear extended. This is a result of both a forward CofG shift, but and more likely from increased drag added below the wing. I mix in 8% up elevator when the gear is extended.
As has been hinted to earlier, EPO makes a horrible material to make a scale model from. Particularly so with darker models often typical of military paint schemes. This is because EPO is very unstable when it come to any kind of heat. I don’t know what environment Freewing of MotionRC fly in but I fly in the comfortable dry high desert of Colorado with the temps around 25°C. I’m showing the cockpit of my Freewing Mirage 2000. This heat damage was as a result of the model being exposed to sun light for about 5 to 6 minutes. The was the time it took me to install the battery, taxi out to the flight line, fly for 2.75 minutes, land and taxi back. As you can see the EPO beads in the cockpit look more like pop corn than anything else! also the darker blue gray areas are starting to alligator (early stages of EPO instability, expansion). Its a bit late for my cockpit, but I’ve cut the floor away to try to give the cockpit some ventilation. I also use did this for clearance of my voltage telemetry sensor. I’m also showing the clearance pocket I made in the aft part of the cockpit/ battery hatch to clear the battery connectors.
Just to be clear EPO is fine (when engineered properly) for trainers and light colored models (white, yellow etc.). But for scale models the surface finish and stability issues, make EPO wholly inadequate. If purchasing an EPO scale model it would be best to think of it as a sport model, not a high fidelity scale model.
With the poor flight control issues (really this can be traced to a poor manual) and the fact that EPO foam is not a durable material for a scale model I’d have to give the Freewing Mirage 2000 a 2 star rating. With some corrections to the manual it would really be a strong 3 star model.
Friends don’t let friends fly foam, well not scale foam models,
Konrad
P.S.
BTW; The tiger paint schemes does show up well, even if only on the top side! While I do enjoy my Freewing Mirage 2000. The kit as sold by Freewing and marketed by MotionRC is not ready for the masses. The manual needs a lot of help. And Freewing needs to aim the control system for computerized radios, not entry level radios. This model is not suitable for beginners or even moderate fliers, as such it should not be crippled by a singe control surface wing.
I’ll start with my initial on line post.
This Delta needs some changes!
I purchased this Freewing Mirage 2000 over two years ago from MotionRC as an ARF kit. Motion RC did not have the Kit Plus option at the time. As with all modern military aircraft the camouflage makes tracking these models very difficult for these 50+ year old eyes! Low visibility gray works!!! On the ground I do like the two tone French camouflage. But as I have to see the model in the air to control it military paint schemes are not appropriate. Luckily there're Mirage 2000s that have been painted in many "Tiger Meet” paint schemes. I’ve chosen to paint mine in the 2004 Tiger meet scheme. The bright yellow, orange and green will make the model pop in the sky, well if one is looking at the top side of the model.
Much to my horror I’ve found the Freewing does not have, nor have they found a paint processes that allows their paint to adhere to the base material of the model very well. This is not only a problem for Freewing but is an issue for all manufactures of EPO foam models. I have yet to find a masking material that will not lift off the OEM applied paint! The best I’ve come up with is to use “Frog tape for delicate surfaces”. And then to lift off the mask (Frog tape for delicate surfaces) I have to warm the mask with a hair dryer, warm only don’t get it hot or the EPO beads will expand.
With all the masking and repainting issues I was having I was shocked to find that I had spent over 12 man hours just to get some color on the model. As this is a foamy I told myself there is no point trying to make a silk purse out of a sow’s ear. It will never look great up close, that isn’t the point of a foam model. So I assembled the model to fly even with some of the tiger strips missing.
As I mentioned earlier I’m using an ARF kit as my starting point, I'm using the Freewing inrunner fan housing with Neu1410/2Y/SE 1850Kv motor and Jet Fan rotor. I’m also using Freewing branded servos. Batteries are Revolectrix 435 series 4600 mAh at 620 grams. Flight testing has reveled some major control issues, predominately with the aileron roll rate. As spec’d and as set up in the instruction manual, the full span control surfaces offer far too much aileron deflection for any hope of controlled flight. Limiting the servo motion at the transmitter results in a large loss of servo resolution and power. This is NOT desirable under any condition. And is a greater concern with the recommended small 9 gram economy type servos than come with this model, as these are NOT of the highest quality nor are they digital (to be clear, they are adequate for a foamy).
With the servos set up to give the desired elevator response one needs to turn down the aileron command input by over half (48%) that of the elevator movement. This is a very bad condition if one hopes to maintain any kind of servo resolution for aileron control.
The manual failed to mention that with delta wings there needs to be much more down elevator movement than up elevator movement. This is because the elevator is reflexed (airfoil) for a positive pitch moment (stability). To fly level inverted the elevator needs to move a great deal more in the “downward” direction to effect the needed reflex in the inverted position. For a balanced feel between up and down on the elevator stick I had to add 150% more to the servo's downward end points in the transmitter menu. Otherwise I had to hold over 3/4 forward elevator stick just to maintain inverted flight.
In my case I moved the push rod one hole closer to the servo axis, for a servo arm length of approximately 7 mm. This still allowed a bit too much up elevator movement. I had to electrical limit the high rate elevator, not the best solution. I plan to slant the servo arms rearward to set up the much needed elevator differential (mechanically). Unfortunately this will result is reversed aileron differential. I will have to address this electronically within the transmitter programing. The proper solution would be to split the wing trailing edge into dedicated surfaces (elevator and aileron). I don’t know why Freewing didn’t go this way. The cost of 2 servos would only have added to the manufacturing cost by about $5 usd. (The 80mm Freewing F-5 has twice as many servos, so servo cost isn’t the issue)
Flight performance is exceptional for a thick winged foamy at 6,000 feet altitude. With the above mentioned power set up the model was drawing 92-90 amps. (My Freewing F-5 with the upgraded Freewing inrunner is drawing about 84 amps [73 amps inflight]). In straight line speed the Mirage 2000 is the fastest of the 80mm Freewing jets. But with the thick foam wing the speed is still in the sedate 100 plus MPH range. I did notice some instability in roll as the aircraft would rock about 2 degrees at a rate of about 4 to 5 oscillations a second. This would be a perfect place for a gyro but with the low resolution analog servos recommended and the poor mechanics of the linkage the true benefit of the gyro might not be realized.
I find that the best balance point is 3mm ahead of the rear most recommend. (This point is found when all three wheels lift off the ground at the same time, none of this upside down desensitize (dampening) stuff). Delta wings are more limited in range for proper CofG. The range given in the Freewing manual is far too wide! It needs to be cut in half! I have found that best CofG to be at 523mm froward from the aft end of the nozzle. With a delta wing it is best to be a bit on the tail heavy side. With a nose heavy delta winged ship, landing speeds are just too high!
Even balance towards the aft end of the Freewing's CofG range I have to cary 1mm of up trim (measured at the widest part of the control surface and against the aft fuselage fairing). From the same point my control surface movement is as follows:
16mm up Elevator
22mm down Elevator
9mm up Aileron
8mm down Aileron
Rudder all I can get. With the low rate set at 40% to control the take off roll and to dampen the high speed taxiing.
Along with the Delta wing mix I have resorted to using one more mix. There is a strong downward pitching motion with the gear extended. This is a result of both a forward CofG shift, but and more likely from increased drag added below the wing. I mix in 8% up elevator when the gear is extended.
As has been hinted to earlier, EPO makes a horrible material to make a scale model from. Particularly so with darker models often typical of military paint schemes. This is because EPO is very unstable when it come to any kind of heat. I don’t know what environment Freewing of MotionRC fly in but I fly in the comfortable dry high desert of Colorado with the temps around 25°C. I’m showing the cockpit of my Freewing Mirage 2000. This heat damage was as a result of the model being exposed to sun light for about 5 to 6 minutes. The was the time it took me to install the battery, taxi out to the flight line, fly for 2.75 minutes, land and taxi back. As you can see the EPO beads in the cockpit look more like pop corn than anything else! also the darker blue gray areas are starting to alligator (early stages of EPO instability, expansion). Its a bit late for my cockpit, but I’ve cut the floor away to try to give the cockpit some ventilation. I also use did this for clearance of my voltage telemetry sensor. I’m also showing the clearance pocket I made in the aft part of the cockpit/ battery hatch to clear the battery connectors.
Just to be clear EPO is fine (when engineered properly) for trainers and light colored models (white, yellow etc.). But for scale models the surface finish and stability issues, make EPO wholly inadequate. If purchasing an EPO scale model it would be best to think of it as a sport model, not a high fidelity scale model.
With the poor flight control issues (really this can be traced to a poor manual) and the fact that EPO foam is not a durable material for a scale model I’d have to give the Freewing Mirage 2000 a 2 star rating. With some corrections to the manual it would really be a strong 3 star model.
Friends don’t let friends fly foam, well not scale foam models,
Konrad
P.S.
BTW; The tiger paint schemes does show up well, even if only on the top side! While I do enjoy my Freewing Mirage 2000. The kit as sold by Freewing and marketed by MotionRC is not ready for the masses. The manual needs a lot of help. And Freewing needs to aim the control system for computerized radios, not entry level radios. This model is not suitable for beginners or even moderate fliers, as such it should not be crippled by a singe control surface wing.
Attachments
Last edited:
