RCP Mig29 V3M3e3 vs V4M3e3

Hi everyone -

Back out at the field again today doing some more evaluating of the Mig29 V4M3e3.  With today's 10 flights with the V4M3e3, I now have 33 flights on this plane in 3 days... :)

Fortunately today mother nature provided me with great conditions in which to further evaluate my new plane, it was calm when I arrived at the field and by the time I left the wind had picked up to about 15 mph (I had to take a 2 hr break from flying to cut the grass on the runway, one of my little jobs I like to do for my club), so great "laboratory" to test several more things.

Firstly, I wanted to try out how it balanced and flew with a lighter weight 2200 3S that I like to use in my FRC Foamies Su35 MK2.  This one from HK.  http://hobbyking.com/hobbyking/store/__21346__ZIPPY_Compact_2200mAh_3S_25C_Lipo_Pack.html

Based on weighing it on my own scale (HK weights are not always terribly accurate), it weighs 165 gr/5.8 oz compared to the weight of my higher discharge 2200 batteries that weight 197 gr/6.9 oz.  Fortunately, with this battery all the way up against the bulkhead, the plane still balanced even though it is just over an oz lighter.  It gave me great top end speed and a bit more agility, so I will continue to use it often.  On the subject of speed, of course I had to finally clock this plane with the lighter battery and the results are pretty amazing.  In four good speed runs, I got speeds of 88/85/79/77 mph with HK Datalogger... :)  My previous top end speed with the stock V4 was 82 mph at a slightly lighter weight with a 1600 battery... :/  WOW!

This is a very interesting result as the gain in speed on all the "speed"  (RCP Mig 29 V3 and V4 and FRC Foamies Su35 MK2) planes I have modified since Stephan and I formed the NAMC (I never really bothered comparing the F18 V3M3e3 as it will never be a speed demon) is in the neighborhood of 6-8 mph increase every time!  In each situation I am comparing stock planes at the same weight versus modified planes with the same power plants, etc.  That is a pretty significant increase in speed and I have to think it is down to reduced drag from smaller control surfaces and good symmetrical sanding of leading and trailing edges.  The exciting thing about this as I have mentioned in other posts is even if speed is not always important, the increase in efficiency in low to mid range throttle settings must also be increased if the drag and turbulence has been decreased... :)

I also tried a bit more high alpha with the V4M3e3 and I am very impressed with how high I can hold the nose.  With the lighter 2200 battery all the way up against the bulkhead, I was holding the angle of attack (AOA) about 5-10 degrees higher than I could with the stock Mig V4.  Part of this increase in stable high alpha with increased AOA may also be due to the shift in center of lift (COL) and centre of gravity (CofG) (as I mentioned, the CofG is 3/4" forward of stock now) Stephan explained in his comment to a previous post, but it is an impressive increase for sure.  So, better top end speed, better high alpha performance, two more amazing discoveries today on this great plane.  

Before I start with my comparisons between the V3M3e3 and the V4M3e3, let me discuss how the V4M3e3 handled the higher wind.  It handled it amazingly well, as I knew it would.  Again, the negative effects of the Elevon Polar Pitch Effect (EPPE) was very subtle when compared to the stock V4.  Overall handling was truly rock solid.  In some ways in the turns, the V4M3e3 reminds me of the RCP F22 V3.  The F22 V3 was not a stable plane at low speed or in wind, but when I was able to keep it on that tight edge where it liked to be, it absolutely carved up the turns.  Where the Mig29 V3 and F18 V3 tracked well, they were more at peace with the air, not carving it aggressively and with attitude like the F22 V3 did.  The Mig29 V4M3e3 does the same thing, but through a much broader speed regime than the F22 V3, it really just carves through the turns like it is on rails, better than almost any other plane I have ever flown.

So, on to the comparisons between the V3M3e3 and the V4M3e3.  I took a few photos at the field to show some of the differences in the tail section where some of the biggest differences are.  With these two planes (the V3M3e3 is the white blue and red plane), I am kind of comparing apples and oranges in performance and handling as the V3M3e3 is powered by the NTM Prop Drive 2700 motor with a 6x4 APC prop and is about 3.5 oz heavier than the V4M3e3.  

In the picture below you can see the differences in the elevons, much more moving surface on the V3M3e3 with considerably more surface area in the prop wash or thrust vectoring (TV) area.  You can also see that the motor is much further forward (I think about 1") on the V4M3e3 than it is on the V3M3e3, also making the back plate much bigger on the V4M3e3.

In the next picture, you can see that we have much bigger rudders on the V4M3e3, the rudder is a full inch longer and makes for a very effective control surface.  It also seems obvious in this picture that on the V4 the intakes/nacelles must be deeper than on the V3 as the wing plate sits about 1/4 to 3/8" inch higher.  I don't know if this contributes to any difference in handling or performance, perhaps it is just an aesthetic change or to help have less of the prop exposed on landing.

What is interesting to note when I modified the V3M3e3, I didn't have much of a shift in CofG like I did on the V4M3e3, maybe a 1/4" maximum, but nothing like 3/4" on the V4M3e3.  Perhaps motor position has something to do with this because we considerably reduced the elevon size and also I extended the trailing edge of the KF to have roughly 40% on the V3M3e3 as well, so I am surprised the CofG didn't shift forward more.  Anyway, I thought that was an interesting thing to note as I feel it affects the stability of the two planes.

The V3M3e3 is definitely the finely tuned sports car/speed demon of my hangar.  On 4S I got it to 109 mph and about the only time it is slow is when it is sitting still.  It is a beautiful plane to fly and I have over 50 flights on it to date.

So, what are my preferences between the two?

I prefer the smaller moving elevon surface and reduced TV area of the V4M3e3.  It just feels smoother and more scale when turning or looping and I think helps with a "quieter" back end in general when compared to the V3M3e3.  It allows the plane to just go up and arch it's back gracefully in a loop like an Olympic diver.  The V3M3e3 is also very responsive in the pitch, but the larger moving surface and TV area causes the elevon to bite a little harder, almost like the plane is digging in it's heels so I have to be careful not to be over aggressive in loops at times.

I definitely prefer the larger rudder surface we have on the V4M3e3, it is very crisp and precise, giving much more immediate response in the yaw when you really want the rudder to do it's job.

The V3M3e3 is definitely heavier and faster, but in all honesty even with the increase in weight, I find it a bit less stable than the V4M3e3.  Whatever "mojo" Stephan and I discovered with the mods we made to the V4M3e3, it is absolutely amazing.  It is more stable, more precise, aerobatic and agile, has better top end speed, better low end handling and better high alpha characteristics than the stock V4 and has more scale handling than the V3M3e3 in my humble opinion anyway.  

I suppose the real true test which I will be evaluating in coming months is to build a V4M3e3 with the NTM Prop Drive and do a true flyoff to see what is what.  But I suppose part of the question is already answered.  I think Stephan and I both agree that stock the V4 is better than the V3, so it makes sense that when we make improvements that the V4M3e3 is going to be better than the V3M3e3 and we have also evolved our philosophy and building in a very short period of time also to make our modifications have even greater impact on the positive aspects of the planes we build.  

With 33 flights in conditions from dead calm to 15 mph winds, the V4M3e3 just continues to blow away my expectations with each and every flight.  As the obvious improvements we were looking for became apparent, reducing the negative effects of EPPE and improving yaw control with better rudders, many other bonuses have come through in flying colors.  Overall increased stability, better scale handling, reduced drag and turbulence, (especially in the back end of the plane) better top end speed, better slow speed handling, better high alpha...not sure what more you could ask for...maybe that it could whip me up a quick espresso at the field once in awhile?!  I'm sure HK must have a lipo powered espresso maker somewhere... ;)

Anyway, the next calm day I will really get it dialed in for some sustained high alpha and hopefully shoot some video.  

The Mig29 V4M3e3 is without a doubt the best overall park jet I have ever flown and exceeds all my expectations...great job, Stephan!  NAMC rocks... :)

Cheers,

Scott