I'm sad to report the loss of my Jet Legend Mig 29. The model was well into it's 49th flight when the fuselage folded as I entered a loop. This resulted in the total disintegration of the back end of the model. The Mig was 160 powered and had been a love hate relationship with me. I had originally placed an order for the Sukhoi SU27, I was led to believe this would be for a single engine but when it arrived it was a twin. the order was then changed to a Mig 29 which subsequently arrived, albeit some 6 months after the original order. After only a handful of flights the undercarriage became very problematic and I had to change to a hydraulic system, to ensure reliability. (JL have since modified the original undercarriage to sort this problem). The model always flew very well and the only comment I got from Jet Legend, as to my loss, was that it flew well because of the lightness of construction. I have previously owned a JL F22 and still own a L39. These models have a totally different thickness to the fuselage skin. The Mig fuselage is extremely thin, and with the model sitting on its belly it would distort to the point that it chipped the paint. The failure occurred just behind the F8 former. This is the former that holds the back of the engine mounting and the rear wing mounting point. Behind this there is no support until where the exhaust exits the fuselage, to compound the weakness there is a very large hatch above some of this area, thus the strength is derived from the floor and sides only. Other makes of models, that I own, have carbon strengthening to this area and an intermediate former to produce rigidity, and I believe the Mig should be reinforced here. It is interesting to note, as well, that all the formers pulled away from the skin cleanly, making me doubt how well bonded the formers were to the fuselage skin. Of equal concern though is the internal structure of the stabs. Will these people never learn. After the problems with the F20 I had hoped for an improvement to this area but the balsa used is the softest know to man, the anti rotation pins are short and there is NO glue!! (However that is an improvement on my F22 that had no anti rotation pins fitted to one of the stabs!).









John

Sorry to see that John []

John, very sorry to hear about this, did you have this one out at CJ earlier this year?
Gary.

Thanks Guys for the words of sympathy. This happened in November, I immediately informed Jet Legend and I have been sitting on my hands to allow JL to respond. Jeff Sewell was sympathetic but I have not heard from the factory since their short reply informing me that the model fly's well because it is built light. I don't like getting involved in internet flamming but I feel I have a moral duty as there are guy's out there buying and flying this model. I have learnt much about the Mig, because it was one of the first to be produced, and I believe it could be a great model with a little more thought by the factory. Whilst they adopt their head in the sand attitude it concerns me that they are producing even bigger models, like the Yak130 without learning any lessons.




John

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John

Very sorry for your loss of what looked like a very nice model.

This does indeed raise concerns because as these models get bigger and bigger they need to build them in a different way to their smaller models. Strength and size are not proportional but exponential and what will do for a 120 and belowturbine size model will not do for a 170 and above.

Looseing a model is a great sadness but should one of these potentially flawed models hit a building or worse people as it fails in the air this would be tragic and of course also worrying for the hobby.

Bod

Wow! This is kinda worrying, my mig should get delivered next week[X(]

Hi John,
Sorry to hear this sad news. However, thanks for the heads up. You are right about the flexibility of the fuselage. Mine must now be grounded until I can strengthen the fuselage. I will be demanding new properly built stabilisers from JL. I think longerons are called for.
I hope JL do the right thing by you now.

Sorry to hear about this! My mig arrives next week too!! Looks like we might need to do some strengthening Carl !! I had heard from a club member that there was a bit of flex in thier fuselage ! Shame you found out about it in that way!

This has definitely taken the shine of getting my new model[:@], I'm also not happy to fly it with those stabs, the fuse I can strengthen before I start the install

I assume that the stabs are still the same on the latest mig's to leave the factory

Hi John, I saw your Mig early last year at Shawbury and followed you trials and tribulations with the undercarriage on another thread. Its devastating when something like this happens and you have my sympathies. It was a superb flying model and a costly loss.
I finally took the bold step of buying my first (and last) artf jet early last year, a JL F22. I was so disgusted with so many issues with the design that I just stored it away without even flying it. Perhaps my expectations were too high. You have raised an issue with the F22 tailplanes. How did you discover the lack of an anti rotation pin? Ron.

The strengthening could be achieved quite easily with carbon and the addition of another former. As for the stabs, I would have opened them up at the bottom and put some hard wood in there with some carbon and glue. That is what I had to do on my F22. It should be alright then, I only wish I had know about it. The only positive is that it happened at Wroughton, where there is alot of space. If it had crashed at my other flying site the results could have been much different as the flying area is a great deal more restricted.




John

HI Ron,
After a harder than usual landing, with my JL F22, I noticed that one of the stabs was trailing on the ground as I taxied in. I thought a servo had been stripped but upon examination the stab was free to rotate around the stab shaft. I cut open the bottom of the stab to investigate and was horrified to find no anti rotation pins fitted. I cut open the other stab and this did have two fitted. I rebuilt the stabs using carbon cloth around hard wood and long anti rotations pins, and had many flights with the model then after.



John

Hi John,
If I were to do the work on the stabs I would not interfere with the integrity of the skins. I would Dremel out the root of the tailplane and then rebuild using plywood blocks. I did this on my FB Hawk as my previous SM one had a tailplane failure.
Sad as I was quite enjoying this model and considering another JL model, the SU27. I am sure you were enjoying your model too.

Like most Chinese jet manufacturers, I think they design their jets with weak-points so that a crash/breakup is inevitable. That way, the company has more sales. Little do they know, it actually scares new buyers away, and their former customers turn to another jet manufacturer.

Thanks for the heads-up on this. When was this jet delivered to you from JL?

Sorry to hear of your loss. I also lost both my JL Mig 29 (about fifth flight) & Large F15 (third flight) with similar problems. It is not just the loss of the airframes, it is all the other parts. When my Large version F15 crashed due to elevator breakup, it crashed & burst into flames. Nothing was salvaged.
I had one other Jet Legend jet, the L39. I quickly got rid of that. It's bad enough losing jets due to pilot error, but worse with structural failure. No more Jet legend for me.

My fleet is now;- Two BVM Kingcats, one aviation design Phoenix, one Comp ARF Flash & I have bought back my faithfull old Avonds F15.

Keep to the smaller jets and I honestly dont believe these sort of problems happen

John,

Sorry about your loss. My Mig 29 has had no problems since I converted the landing gear to hydraulic. I've probably got 25/30 flights so far on a JetCentral Rhino. Your dissecting of the stab has me worried as that is exactly where my F-20 failed due to soft wood in the elevator. Now, what to do. Cut into the elevators and perform surgery before I have a problem or hope that mine has the proper pinnage? The fuse, as you mentioned, is very thin. Perhaps the thing to do is fly this airplane very conservatively and don't put it through the paces as we normally would.
Again, sorry for your loss.

Rob Puetz
F15driver

so how many Jet Legend products have you had that have had problems that have led to failures.....??

What's the point in owning a fighter jet that you would have to fly conservatively. The chinese manufactures are not listening or learning. The so called improvements they make in one area only magnify the next weak link in line. It's to bad because the chinese manufactures have airplanes that none of the other manufactures have, but it's just not worth the risk IMO. I'm sorry to see the loss of the Mig, there sure have been a number of JL failure threads lately

My typical flights were pretty smooth I think. It wasn't a particularly fast model and I always tried to fly it smooth and scale like.
http://www.youtube.com/watch?v=Z48ac...VnYZlo3AIFnhaz



John

Let's hope it's a one off! and that jl maybe replace the balsa in the stabs for harder wood if they haven't done so already ! although to be fair I beleve the stabs have not caused a Mig crash yet!!

This is a never ending dilema. The Chinese models look great, but if you fly them as is, you are probably in store for a suprise sooner or later. You MUST, look them over, install reinforcement as needed, where you see the need. If you don't know what to look for, find someone who does. That includes looking inside the wings, stab connection points, pivot points, wing attachment, former glue joints , landing gear function and durability, ect. If it requires opening up a structure, buy a scope / monitor, and peek inside. The other option is, wait a couple years for reports of failure, and hope the Chinese fixed it.
I'm sorry for your loss, it's very dishearting to spend good money for display quality jets, that are lacking in good old fashion American Engineering, that is still available, but people, ( me included ) really don't want to pay for. You can buy a beautiful looking molded scale jet, for $1500, the insides are balsa and hot glue. Maybe it stuck, maybe not. They are selling wings with balsa spars. As a builder, I'm amazed they last through one fighter style flight. A while back I contacted one supplier about " D " tube spar building, which is top and bottom hardwood spars , with balsa shear webs, ( vertical grain ) face glued in between. No response. It's not going to change, as we keep buying them. I've been doing this for 32 years, for what it's worth.
Thanks,
Dale

i had a unfortunate crash with a runway light with my jl l39 and both wing panels had to be rebuilt, while this was being done the club mate who was rebuilding them for me told me that there was nearly no glue on most of the gear mounts and most of the skins were not attached to anything, thankfully this was put right before anything nasty happened.
you would think that after the years that jl has been around they would do somthing about their quality control, it cannot be that hard to check were the glue goes and the strength of the finished product, maybe if every one stopped buying them untill they resolved the short falls in their workmanship they would try harder to get a better name for top quality jets and make the same profits that way.
but we all know that that will not happen.