MIg-35v2 NAMC
RTMS (Roll Tide Mig Shop) division of NAMC has been quiet on the blog but hard at work in the shop. After the NTM Prop Drive 2700 destroyed my Mig-35 it was time to build another. All I have left is the Mig-29v4 with stock elevons and NAMC vertical rudders and inboard ailerons.
Approaching this build, I had several ideas and goals. I continue to seek the Hloly Grail straight line knife edge. I’ve accomplished the knife edge turn, but going straight continues to elude my pilot skills. To help attain this goal, I felt like I needed more rudder authority. As previously mentioned in a post, when in high alpha only the inboard rudder is truly generating yaw. Additionally, I’ve wanted more yaw in rudder stall turns. So for this build, I went supersize on the rudders. Other goals include more scale like appearance and less frontal area to further decrease drag.
The larger vertical stabilizers that Scott designed gave me plenty of room to increase the size of the rudders. I was initially concerned that the vertical stabilizer at the top front corner of the rudder would be a weak point. However, with glassing the vertical stabilizer is very solid and I have no concern for structural weakness. I gained a lot of authority on this set of rudders. On my Mig-29v2 it has straight rudders the length of the vertical stabilizer, Scott has these on most current. This style rudder is perfect for all desired yaw maneuvers except for knife edge. So if you have no desire yet to knife edge, go with the simple straight full length rudders. Here is the rudder drawing:
On his latest build, Scott went with a longer tapered aileron. When I did my initial flight testing of ailerons on Mig-29v3KNEx, they were straight. With Scott’s extensive flight testing (a gazillion test flights :o!) and positive review of a tapered aileron, I went with that design on this plane. I maintained the same surface area as my inboard ailerons on my last build, I just halved the width and doubled the length maintaining the same taper as stock. I still believe these planes they fly better with less disturbance at the wing tip. Every time I fly high alpha I turn my ailerons off and wing rock is comes on much later. This is the easiest experiment you can do if you are non believer. Program a mix with your dual rate to turn off your ailerons. Try it, you’ll be amazed at how much more stable slow flight and high alpha is as well as high speed mowing the grass fly byes. Here is the aileron drawing:
My last goal was to decrease the frontal area and drag along with a more scale like appearance. The first thing I did was to take a 1/4 inch off of each end of the canopy. I then tucked the sides under the end pieces. Personally, I’m extremely happy with the improved look. I pasted in the scale Mig blueprint plans as well as the SebArt Mig-29. Look up the SebArt, it is an amazing thrust vectoring ducted fan plane. I would own one but it falls into the “balsa” class of planes for me. I’d never enjoy flying the plane for the fear of crashing it (something I’m quite proficient at). No tears in my beer over another plane. Been there done that, ain’t goin’ back. And yes, I have a drawer full of t-shirts. Anyway, back to the topic. I studied the wing and fuselages of the the v4, scale and SebArt. The v4 is too long and I have not figured out a good way to shorten it—that is a winter project. The LERX and the leading edge of the v4 wing are larger than both the scale and SebArt. The wing trailing edge distance to leading edge of the horizontal stabilizer is good. So I scaled back the LERX and the wing leading edge. This will decrease the lift, push back the center of lift as well, and increase the wing load. Hopefully, this will result in faster and “sharper’ flying plane that flies more scale like as well. I hope that high alpha will not be adversely affected. The look though is winner. Check out how the outer nacelle curves in. Here are the drawings and the plane:
For the paint job, I had to copy Scott. I tried to mimic the Azerbaijan Air Force camo scheme. This is by far my favorite paint job. For the stickers, I print them on regular paper and covered them with packing tape. I cut them out and glued them on with Alene’s. Why is the Canadian flag on the wing tip? Of course it is to pay homage to my Canuck partner and
One last comment, I recycle all of the electronics and tested them all but the motor. One of my servos from my last crash was bad. I didn’t test the FP 2700, but I had to change it out. It beeps then just stutters and moans. Until Scott finds a new source, I’ll try the Turnigy and Grayson 2200s.
After I sort her out, I’ll put together a build video with some flight highlights at the end.
Build Highlights
Tapered cockpit
Narrowed LERX and wing leading edge
4mm carbon wing main and 3mm leading edge
True 40% KF4 with dollar store foam
Narrowed nacelle
Downsized tapered ailerons
NAMC Elevons
NAMC Vertical Stabilizer
NAMC Outboard servo placement
NAMC RTMS Inboard vertical rudders
16oz without battery
Blue skies to you,
Stephan
Nice job i love the way that cockpit looks not so square. Excellent paint job look forward to a video in near future. Hope you get that knife edge down i love doing them just haven't been able to do in on any jets yet except the new rcp v4 F118 i was able to get it for a little but it might have been the wind helping me haven't had it up much since then due to my back injury around same time i finished plane.
ReplyDeleteThanks for the post i enjoy them.
Blue skies
Rob
Rob,
DeleteThanks for the compliments. I have to admit, I was very pleased with this paint job. Waiting on the wind to die down so I can maiden her.
Stephan
Hi Stephan -
ReplyDeleteExceptional build and write up as always, Stephan, I love the ingenious little tweaks you made to improving the look and the sleekness. It is obvious right away when you see the two of them side by side the difference in the LERX and leading edge of the wing. I'm excited to see how it handles and flies.
The new ailerons and rudders look awesome also, with that much rudder you should have tons of authority, that is about the same surface area I have on my NAMCV2, just shaped differently, but I think you will notice the extra authority pretty quickly. I'm fascinated by the new aileron too, I have been finding the narrower in chord and longer in span aileron on the NAMCV2 to feel a bit crisper than the deeper and shorter aileron on the NAMCV1. I'm interested to hear what you think. I will definitely use the canopy mod on my F18 V4... :)
A beautiful finish and paint scheme, thanks for the Canadian flag tribute... :)
Sorry to hear about the FP motor, I actually had one cut out on me in the air the other day, I managed to land OK, it was doing the old "stutter step" every time I applied power, wouldn't run properly, so I disconnected power, disconnected the three leads that run to the motor, then reconnected everything and it seemed to "reboot" the motor and ESC. It might be worth checking the timing on the ESC to see if maybe that is off, just spitballin' ideas here.
I hope that the Deal Extreme motor is the same as the Focal Price motor, should have it in the next few weeks I hope and if it is, I'll order a bunch of them to have my own supply stock in the event they run out of stock also.
Another revolutionary and awesome looking Mig from the RTMS, I can't wait to hear how it flies, great job my friend!
Cheers,
Scott
Scott,
DeleteIn my daily job I have to MSU it (make shit up) because no two people break the same way. So when I am building these planes, I always look at doing some MSU.
I agree with you, this plane with canopy, LERX and leading changes looks very sleek and fast. I hope the changes translate into improved flight characteristics as well.
As to the FP, I'm thinking it is the one that got a bath on F18 I flew at the lake. I'm going to squirt some WD40 in it and see what happens. I tried every combination of wires to no avail.
I look forward to hearing about the Deal Extreme motor. I sure have enjoyed the FP 2700.
If the wind slows down tonight and the pager stays quiet. I hope to maiden if I didn't just jinx myself.
Take care,
Stephan
Hi Stephan -
ReplyDeleteWas doing some thinking about shortening up the total length, I will have to measure to see how much we have shortened the plane overall with the smaller elevons. I'm with you on this idea for sure... :)
I looked at the wiki sites for both the Mig29 http://en.wikipedia.org/wiki/Mikoyan_MiG-29 and the Mig35 http://en.wikipedia.org/wiki/Mikoyan_MiG-35
Interestingly, the Mig35 has a 39' 4" wingspan which is about 2 ft more than the Mig29 at 37'3". When I look at pictures of the Mig35, it does look a little "squatter" than the Mig29. Surprisingly, wiki says they have the same wing area of 409 sq ft.
So I took a few length to wingspan ratios -
Mig29 - 57' long by 37' 3" = 1.53:1
Mig35 - 56' 9" long by 39' 4" = 1.44:1
So if the Mig29 V4 is 41" by 27" the ratio is 1.51:1.
I agree with you, I like the shorter, squatter profile of the Mig35. To match the Mig35 ratio, the Mig29 V4 would have to be 39" long. 2" might be a lot to trim off, but when I look at pictures, I think the length of the nose from the canopy forward could be shortened a good amount if we stay with the Mig35 theme. I know the Mig35 is a 2 seater, but the canopy is big enough I think to stretch the imagination that it is a Mig35.
Then trim a little off the back end, we reduce the size of the back plate a bit more as well (say a 1/2"?). To keep the ratios and scale the same since we are moving the horizontal stabs and elevons forward a bit (not sure how much, but not too much, we might have to trim a bit off the trailing edge of the V4 wing (say 1/4"?) to keep the distance between the horizontal stab and wing looking about the same. We could also trim back the horizontal stab back a little too to keep that look.
Even if we lost an inch total or slightly more, we are moving closer to that Mig35 ratio and look. If we lose a little bit of wing area, so be it, it would bring the wing closer to the V3 wing size. I am still searching for a good 3D planform view of the Mig35, wiki doesn't seem to have one.
I couldn't wait any longer, I just finished measuring my stock Mig29 V4 and my NAMCV2. The stock Mig is actually 40 and 3/8" long. I probably did shorten it up a little after some nose repairs... :/ The NAMCV2 is 40 and 1/8" long.
If we take 1/4" off the back along the hinge line of the elevons we are using on the NAMC planes, we reduce the surface area of the back plate by 3.25" sq inches just by doing that, again helping to reduce EPPE. I don't think we need to mess around with the trailing edge of the wing if we do that. Then maybe shorten the nose up by 1/2 to 3/4"?
This would definitely make it snappier in the pitch and overall aerobatically I am thinking as well, maybe even trim just the tiniest bit more off the elevons also? Say about an 1/8" all the way around to keep things scale?
Anyway, just ramblin' and spitballin' ideas a bit here, I think it is very doable without messing up the plane too much and in fact I suspect make it a bit more nimble. The FRC Su35 is actually shorter than scale compared to it's wing and it is pretty insane in the pitch. So I'm not saying making it that much shorter, but close to two inches shorter if planned out right would really make this pretty insanely aerobatic and it would probably look a lot more like the latest version of the Mig, the Mig35.
Cheers,
Scott
Scott,
DeleteI've been looking hard at these plans trying to "shrink" the length. Forward of the bulkhead is where it has to happen unless we move the motor back to maintain CG. Batteries are already pretty far up in the fuselage.
I will do some more playing around with my drawing software when I get some time and try to figure this out. As you can see, I prefer to translate my drawings to measurable changes on the plans--allows for repeatable modifications by those who choose to do so.
Keeps that brain churning on where we are headed next with the NAMC Mig. Once you nail the Su, I might have to build one. Though the thoughts of adding to FRC coffers is less than appealing.
Take care my Canuck friend,
Stephan
Hi Stephan -
DeleteYes, I was thinking that too. I wonder if we just moved the bulkhead forward a bit, just cut some off the back of that centre nose piece behind where it goes up through the top to attach the canopy. If you look on page 3 of the tiled plans, hopefully you know which piece I am talking about. Then just adjust the slots forward on the fuselage to accommodate trimming some off the back of that nose brace piece. I just measured it on the plans, there is 1 and 3/4" behind that "neck" piece that sticks up and goes up into the canopy. I think we could trim about 3/4" off that back part without messing up the angles too badly.
Then for the forward part, if we make the nose section a little shorter, we could trim and taper some off that front nose brace ahead of the "neck" part to ensure the shorter nose still holds a sleek shape without tapering in too fast and looking too blunt.
I'm sure the nose brace piece could be trimmed down to help the shorter nose and to give us more room forward for the battery without screwing it up too bad. Again, just spitballin' at this point.
Our weather forecast looks bad for flying the next five days, either rain or wind or both, so I hope to have the Su done this week. As you will see from the build video, it is a bit more fussy build than the RCP planes, especially with the lessons I have learned from several builds and the tweaks I have made to make the build go together more easily. I am also covering my mods on the video for you and others that might want to try out the mods on the FRC Su. Big grin to your last sentence of paragraph 3... :) I'll leave you with that dilemma... :)
Hope the RC planets align for you to get to maiden your awesome new Mig today... :)
Cheers,
Scott
I love how the prop slot is cut out in reverse of how most people cut theirs out. If you think about it, it makes sense to have the cut of the rear of the slot pointing towards the necel (or however you spell it) of the motor, and the rest of the slot pointing away from it. Most of the wind turbulence is going to be away from the necel, since there is no actual propeller there. You need the most space away from the prop where there is the most wind turbulence being created. Genius.
DeleteMark,
DeleteWelcome to the NAMC forum and thanks for posting. Scott and I spend a lot time validating ideas. You are absolutely right about the prop slot. RCP uses the same shape on most of their planes. While it may be aesthetically more pleasing, it does increase turbulence and hence decreases thrust. There are some great posts, including a scientific one, on the RCP forum about prop slot changes. The most efficient is two ellipses end to end. For me, it just doesn't look right. I'm not going to take credit for genius compliment, but thanks anyway!
As you know, life and aerodynamics are about compromise. In choosing the shape of the leading edge of the tail plate (back of the prop slot), I had two goals. First of course was to improve air flow. Secondly, was to decrease the surface area of the tail plate. Scott and I noticed a long time age an undesirable flight characteristic in these park jets. When they get up on their side in a turn, they were very prone to adverse yaw when wind hit the big tail. We call this Elevon Polar Pitch Effect (EPPE) aka tail washout and weather vaning. To decrease EPPE, Scott and have experimented with reducing the elevons and the tail plates. The combination of these two have given us the best results.
One final note about the prop slot. I also fly dollar store foam Bombats. As you can imagine, we crash a lot. So I have tried different slots. The tighter the slot, the louder the plane. So if you want a screamer, make the slot as narrow as possible.
Probably more rambling than you wanted.
Still too windy to maiden the Mig-35v2. I getting antsy to get this one up in the air.
Blue skies to you.
Nice work Stephan and Scott. I personally like my prop slots cut slightly more back than stock. I feel that if it's too far back, the plane looks a lot less scale and (there's a gaping hole in the middle of the plane). It also doesn't look aesthetically pleasing to have such a giant hole. I agree with you completely that it's too noisy to have the slot cut just outside the propeller, tool. It's all about personal preference I guess.
Delete-Mark
Hey thanks, Mark. Yes on these planes it can often be about tradeoffs, performance versus aesthetics or modify one thing to help one part of the flight envelope and sometimes it affects another part of the flight envelope. It is all part of the risk/reward of playing around with modifying these planes. So far with the Mig we have been pretty lucky, I don't think any of our mods have really screwed anything up too bad, but then again I'm a bit biased... :)
DeleteThe Mig29 V4 has been a bit trickier to make the back end smaller and prevent EPPE or tail washout in crosswind turns as RCP made it a bit wider than on the V3 and with the motor mount now being further ahead on the V4 than the V3, that increased that large surface area back there as well.
I think as Stephan mentioned we have it pretty much dialed in now between smaller elevons and slowly reducing the size of the back deck plate through modifying the prop slot. Sometimes it is also a matter of where the prop disc ends up depending on the motor being used. The FP 2700 motor unless you cut some of the shaft off puts the prop disc further back than say the Turnigy D2826/6 and then of course the NTM 2700 is just a big motor with a big "can" and large prop adapter than needs the extra room to "breathe".
I have also found that by symmetrically shaping the trailing edge of the prop slot that the airflow is smoother and the prop is quieter. I used to just use the old chisel shape like I did on the leading edge of my wings and elevons, but since I started symmetrically shaping and sanding everything on Stephan's recommendation, everything is so much smoother in every aspect of how the plane flies and handles.
Thanks again for your kind words... :)
Cheers,
Scott
MSU love it lol ;)
ReplyDeleteRob
Hi Stephan -
ReplyDeleteMore thoughts churning around in my head for shortening or modifying the Mig some more, I was looking at some pictures of the most up to date Migs through the MigFlug Facebook page https://www.facebook.com/MiG29FulcrumOfficial and I noticed that on the Indian Air Force Mig29UPG that the LERX go quite far forward, almost up past the front of the canopy. In fact I think on the real Mig that is the case on most of the models.
So as we were talking about shortening the Mig29 V4, it would still look scale if the LERX were extended forward or the nose section pulled back somewhat or a combination of both to shorten up the length of the fuselage. I understand it still requires modifying the bulkhead and nose former part so that we maintain or increase the area forward for the battery.
I watched this excellent video on You Tube which has some great footage of the Mig29 OVT with full thrust vectoring and the Mig35. Both look to be a bit "stubbier" forward of the intakes than the V4, but maybe just my eyes playing tricks on me. There is some great footage in the Mig29 OVT that is split screen showing the plane doing a cobra and what the elevons are doing through the maneuver, very cool. https://www.youtube.com/watch?v=fOzp7iL-QHI
Brain is always churning on how we can shorten up the Mig29 V4 and bring it in line with the more modern versions of this great platform... :)
Cheers,
Scott
Scott,
ReplyDeleteThat video was awesome! Just amazing how the Russian pilots push the human envelope of the flight spectrum. I'll figure out how the shorten the fuselage--my next project.
Having a great time in Cancun.
Stephan
Hi Stephan -
DeleteYes that Mig29 OVT with the thrust vectoring is very impressive, I have watched a lot of video on it performing at different airshows, always amazed at the moves it can perform. I have been attempting those sort of slow "tumble loops" and they can be done, takes a bit of power just as the nose goes through vertical to get it to come over the top quickly, then I have managed to do a couple consecutively before my lack of skills puts me into "auto flail", another very impressive maneuver... :/ But fortunately the Mig recovers quite easily.
A decent cobra still escapes my abilities, I continue to try one, I think like high alpha or slow flying it almost needs dead calm air to keep the plane from getting blown around or I don't let go of up elevator in time and end up flipping over, oh well, another challenge to take on this winter including working on some more inverted flying.
I think having a shorter Mig like the Mig35 (in relation to it's wingspan) and putting more weight concentrated around the CG will allow for some even better aerobatic performance, especially in the pitch and yaw since there will be less airframe resisting the control inputs in those two axes.
Glad you are enjoying your vacation, you deserve it, my friend!
Cheers,
Scott