Official Freewing MiG-29 Fulcrum Twin 80mm Thread

[GliderGuy]

I think you are doing exactly the right thing and if i didnt already have one, i would be doing the same!

A fundamental question remains: Were the MiGs that crashed using the ferrite RF choke noise filters?

I lost an F-4 and an A-10 twice (1st was repairable) with this EXACT same “loss of elevator” happening. Since installing the RF chokes on my HIGH CURRENT ESC planes, none have experienced problems.

Search this and the F-4 forums on the word “ferrite” to see the prior posts.

The answer may possibly be this simple....or not. Hard to ignore approximately 2,000 total flights without problems with the F-4, AL37 and MiG after installing the RF chokes.

Logical? I am not betting otherwise ever again.

-GG

[Skosh25]

@GG- after reading your RF choke gospel MANY times , I purchased some and installed in my MiG-29. Piece of cake for piece of mind (as James would say). I can't find any reason not to do it. They are super cheap and weigh basically nothing. Whether it helps or not is probably TBD. But in my mind it couldn't hurt. I've also bypassed the BB (elevator only), added a capacitor, beefed up the elevator linkages, put in some crow to ailerons and flaps, and I have D85s on order.

[GliderGuy]

I know I am being a repetitive post hog in this regard. I appreciate everyone’s indulgence.

I just hate to see folks crash, if it is avoidable. Worse yet, the easy/cheap/light-weight potential “solution” gets buried in past post archives w/o being read or considered by those recently receiving their planes.

-GG

[Airguardian]

https://youtu.be/cLwenDNqdQ0

Another crash. Kinda appears to stall in the turn, but it could just be the angle the video was shot.

That's anything but a stall.

[Waconut]

I know I am being a repetitive post hog in this regard. I appreciate everyone’s indulgence.

I just hate to see folks crash, if it is avoidable. Worse yet, the easy/cheap/light-weight potential “solution” gets buried in past post archives w/o being read or considered by those recently receiving their planes.

-GG

Where is a good source to order the Ferrite rings?

[Skosh25]

These are the ones I purchased:

https://www.amazon.com/dp/B07CWCSNW9/ref=cm_sw_em_r_mt_dp_cdAJFbQ9CRMR6

[GliderGuy]

These are the ones I purchased:

https://www.amazon.com/dp/B07CWCSNW9..._cdAJFbQ9CRMR6

Yes....correct.

Note these are clip-on barrel type / not ring type.

Multiple wires can route through one. Thus, you can use 3. One for each ESC sitting back by the rear battery on either side, and I used a small one to add to the wire going from the UBEC to the receiver....adding it to the wire that already has the green ferrite ring.

Best to get the 2 bigger ones (multiple wires through 1) as close to the ESCs as possible....back by the rear wall by the rear of the back battery.

-GG

[Waconut]

I placed the order, I will add them to my current fleet of 6 FW EDF’s.

[GliderGuy]

I placed the order, I will add them to my current fleet of 6 FW EDF’s.

Place them on all the ESC wires....see below. As close to the ESC as possible.

I added a small one right by the green ring choke that is already there....probably overkill.

-GG

[janmb]

https://youtu.be/cLwenDNqdQ0
Another crash. Kinda appears to stall in the turn, but it could just be the angle the video was shot.

I don't see it turning at all. This was during straight flight, and as far from a stall scenario as you can pretty much get.

Looks a *lot* like the tons of similar crashes we've seen. Pity we still don't have the common root cause for all of these. While they obviously don't all have to have exactly the same cause, so many independent, similar mode crashes strongly suggest so

[janmb]

Hi guys!
This is it my maiden went perfect 🥰 4 flights just perfect! I wrote everything about batteries and throws in the description of my YouTube video here :
https://youtu.be/FFD4Xx8A7lA

Great job, congrats!

[lusek_pl]

Hello everyone, all these failures are worrying. I am waiting impatiently for the available model in Europe, although stupidly to lose 600 € in a few seconds ... because there are still no 100% causes of failure. Isn't the elevator lever at a great angle to the servo? And there is a lot of mechanical stress that is blocking the servo? If it was about ESC disturbances, the failures would not only apply to the elevator ...

If it were parallel to the control surface?

[janmb]

Freewing/Motion help us get these birds in the air, without it feeling like Russian Roulette as to whether they will come back!

Yeah it would certainly be great if alpha & co made an effort to debug any potential aerodynamic explanations for this (by trying to recreate the modus of these crashes

Easier said than done, but should be attempted anyway

[GliderGuy]

Careful....no confirmation that “only” the elevator control was lost. That’s just the most critical to keep one from diving into the ground.

That elevator only loss assumption is not supported, I don’t believe.

When I lost the F-4 and A-10 (twice), none of the controls worked (high up...tried everything). I replaced the receiver in the A-10 after the first crash.

-GG

[ArthurJ]

Great job, congrats!

Thanks buddy 🥰🥰

[kallend]

This may not have been very scientific,

Exactly. Doing it properly shows that there is a very noticeable temperature effect on LiPos, which is why serious competition fliers warm theirs prior to competing.

If you have an IR meter you can see for yourself.

[xviper]

With more and more new videos showing up on this plane, what can we deduce from all the successful examples and all the crashes? The latest one was not really flying very fast at the time of ELE loss. If it was the rods bending from load, we would have seen some response, just not as much. There was NO response at all! I've had planes where the elevator rod bent like semi-boiled spaghetti and yet the plane still had some response so the plane could still pull up slowly with full stick.

Taking only the crashes into account ................................................
Original servos for elevators - crash.
New upgraded servos for ELE - crash.
BB left in play - crash.
BB taken out of the equation - crash.
Book CG - crash.
CG back 10mm to 15mm - crash.

We still have no evidence of crashes when RF chokes are used so can't conclude anything there ................ yet!
When ELE was lost, seemed like throttle still responded. What can be said from this?
Still no data on crashes and successful flights when referencing receiver/antenna placement.
Still no examples of crashes when the elevator rods have been beefed up.
Loss of ELE was momentary (~2 seconds), then came back after altering throttle. What could this mean?

OK, let the guessing and armchair diagnostics begin all over again.

[Waconut]

I am afraid there is still an unknown piece to this puzzle.

[xviper]

Exactly. Doing it properly shows that there is a very noticeable temperature effect on LiPos, which is why serious competition fliers warm theirs prior to competing.

If you have an IR meter you can see for yourself.

But I'm not a "serious" competitive flyer and from my perspective, it didn't matter. Most RC flyers are not competitive flyers either. Same punch when taking off under my flying field conditions. Same flight characteristics. Same flight times. Knowing all this, seeing the IR readings don't mean anything to me and won't change how I do things on this topic. I just care about what I get out of my batteries at the field. There was no "noticeable temp effect" for us. I compare this to "pros" using a micrometer. We used a yard stick. I'm not telling anyone to do this or that, just relating my experience. If you want to buy battery heating bags, please do. I don't even think 50F is "cold", but that's just the way different people see things.
It's like professional race cars. Nitrogen in the tires means a lot to them and can win or lose a race. For the average everyday domestic driver? Really, nobody cares. (Except that the owners can brag, "I've got nitrogen in my tires!") But hey, if it matters that much to some people, by all means, go to the garage to get that tire top up whenever the pressure drops - and they do drop even if you have nitrogen in them. I'll just keep topping up with regular 80% nitrogen type air in my garage.

To the original poster who brought this subject up. Please come back and tell us what happened AFTER you cleaned all the stuck on grass build up in your fan area. Fly it with the same batteries at the same temp exactly the way you did the last time when it couldn't get off the ground.

PS. PieterO This is what he asked ...........................

What do you think? Would it help?

My response was to him. It was based on my own experience. It was not designed to target anyone else. It was not meant to be a collision course with anyone else who might need to "correct" me or to "show me the light" or to show their immense intellectual prowess. It wasn't meant to be scientific and I said so (I was in medical science for 21 years, so I know about scientific process and what it can and cannot prove). It was purely to respond to him because he asked. If PieterO doesn't like that response, well, that's up to him and HE can take it up with me. If anyone else doesn't like my response, well, it wasn't meant for you. Fine, state your facts but I really don't need to "see for myself". If you're not PieterO, keep me out of it.

[Parpoppet]

Hi everyone my first posting to this great site.
I have just received my Mig29 here in uk and will shortly start the assembly. I have been taking note of the blogs regarding the possibility of the elevator causing planes to crash or lack of response. I shall be upgrading both the servos to D85mgs and elevator push rods to the suggested F14 swing wing rods. Also will bypass bb and use two channels for elevators. I do wonder if a possible cause or certainly may add to the problem is the very light weight servo extension leads used for the elevators considering the length of the run. Surely when the servos are under heavy load they will demand more power the lightweight leads will create a resistance to the demand required by the servos under stress and heavy load. I shall be upgrading these servo leads to a heavier higher quality leads I would have thought that this has got to help and certainly can’t do any harm.
any thoughts?