Hawk crash
09-20-2013, 06:55 AM
#28
The spar length is an issue yes, although, had that spar, even that short been built into a proper plywood box it likely would have been fine. However, even if the stab spars had been plywood, the way they mounted the aluminum spar with bolts through the stab spar it eventually would have failed. Why they seem to have such a difficult time understanding that a spar like that should be 100% encased in a box that is glued to spars and the skins is completely beyond me. But then why they feel using honeycomb for a spar is a good idea makes no sense either.
I remember building jets years ago that used aluminum blade spars, they extended into the wings only maybe 4 inches (more than this I know but a wing is also a hell of a lot bigger) but they were glued into plywood boxes that fully supported that spar. In some cases those spars only went into the fuse 2 1/2 or 3" but again, they were completely enclosed in their receptacle. It's all about properly transfering the load.
I'm curious who you bought the airplane from?
I remember building jets years ago that used aluminum blade spars, they extended into the wings only maybe 4 inches (more than this I know but a wing is also a hell of a lot bigger) but they were glued into plywood boxes that fully supported that spar. In some cases those spars only went into the fuse 2 1/2 or 3" but again, they were completely enclosed in their receptacle. It's all about properly transfering the load.
I'm curious who you bought the airplane from?
Y/A jets have aluminum blade spars just like the ones you described. In the F-18, the spars are only glued into a foam core! The thing is, someone understood the load distribution concepts you're talking about when they designed the wing. When built per instructions, you need to crash that wing to get it to fail.... not the other way around. This stuff isn't voodoo. You can learn these concepts if you have a mind to.
09-20-2013, 07:02 AM
#30
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Oh man. Sorry to hear this. One modeler to another, glad you are okay.
...misuse of material.
Instead of pretty pictures of FEJ planes they better start posting x-rays.
...misuse of material.
Instead of pretty pictures of FEJ planes they better start posting x-rays.
09-20-2013, 07:22 AM
#31
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I'm glad you're OK to fly another day! I'm really glad that you posted this so that other people can be warned of what they are doing and buying. Support real manufacturers like BVM!
Gene
Gene
09-20-2013, 07:29 AM
#32
Who in their right mind would put bolts thru a honeycomb spar? Oh yeah, better put a bunch then! Or end the CF reinforcement right at the critical stress point? Really hard to fathom the logic there. I think they just used whatever material they had lying around, and they have a lot of honeycomb F/G lying around.
Is that the Hawk you have dubd? Or do you have the Skymaster?
Is that the Hawk you have dubd? Or do you have the Skymaster?
Last edited by husafreak; 09-20-2013 at 07:31 AM.
09-20-2013, 07:38 AM
#34
Why anyone continues to buy anything from FEJ, after all that has been demonstrated not only with the sub-par (I'm being kind) engineering, but with their complete disavowment of responsibility for their crappy product, is beyond me. Honestly, I am so glad that you were not hurt. That easily could have been a terrible tragedy.
09-20-2013, 07:40 AM
#36
Who in their right mind would put bolts thru a honeycomb spar? Oh yeah, better put a bunch then! Or end the CF reinforcement right at the critical stress point? Really hard to fathom the logic there. I think they just used whatever material they had lying around, and they have a lot of honeycomb F/G lying around.
Is that the Hawk you have dubd? Or do you have the Skymaster?
Is that the Hawk you have dubd? Or do you have the Skymaster?
09-20-2013, 07:59 AM
#37
Looks like the exact same failure Ali had with an FEJ hawk in Kentucky this year. Yet This happened back in February I'm sure they still claimed it was not their fault but the builders ...whatever. Knowing they have a problem they go to an event where the whole world is watching and as usual they didnt fail to disappoint.
Its their ARROGANCE throughout this whole ordeal that started with dubds f14 that has been the most upsetting part.
Its their ARROGANCE throughout this whole ordeal that started with dubds f14 that has been the most upsetting part.
09-20-2013, 08:13 AM
#39
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Little clowns at FEJ have no clue of composite materials.. the Honeycomb is used in all areas of the wings .NICE,.. But most of it in WRONG direction (ONLY THE SURFACE AERA OF THE WING IS OK) but for spars, ribs, etc etc.. is completely wrong direction.. no strength and or stability.. they though build everything of honeycomb and that should do the job. What a joke! Pay high dollars for them to play with some sandwich material.
09-20-2013, 08:28 AM
#40
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Most of these scale jets although they seam fast, are slow compared to JMP and some of the BVM high performance sport aircraft. I'm glad they know what they are doing. Just saying...
09-20-2013, 08:38 AM
#41
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Hey Peter, absolute total bummer, these guys really need to get out of business or fix their problems and take care of the customer that sacrifice Jets for their research and development.
It just a damn shame
FEJ beauty is only skin deep, the rest of it is ugly to the bone
Angus
It just a damn shame
FEJ beauty is only skin deep, the rest of it is ugly to the bone
Angus
09-20-2013, 08:49 AM
#43
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Looks like the exact same failure Ali had with an FEJ hawk in Kentucky this year. Yet This happened back in February I'm sure they still claimed it was not their fault but the builders ...whatever. Knowing they have a problem they go to an event where the whole world is watching and as usual they didnt fail to disappoint.
Its their ARROGANCE throughout this whole ordeal that started with dubds f14 that has been the most upsetting part.
Its their ARROGANCE throughout this whole ordeal that started with dubds f14 that has been the most upsetting part.
09-20-2013, 09:32 AM
#44
What's wrong with you people!!! Always bashing FEJ!!! They care about what they sell you!!! They are soooooo thoughtful and are so wonderful to bring so many new models out there so we can have the jet of our dreams!!
Get out of here you FEJ haters with all your crashes and pictures of your airplanes blowing up!! What are new modelers going to think??!!! Jeez, I'm so embarrassed to be a jet pilot with so many FEJ haters around me!!!
Get out of here you FEJ haters with all your crashes and pictures of your airplanes blowing up!! What are new modelers going to think??!!! Jeez, I'm so embarrassed to be a jet pilot with so many FEJ haters around me!!!
09-20-2013, 10:06 AM
#46
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(FACE PALM) In this day and age all you have to do is spend about an hour on the internet to research the fact that whoever built that stab probably had some sort of excessive drooling problem. You dont have to be an aero engineer to make something that is safe, you just have to care enough to know how to do it right and to figure it out. Unbelievably sad.
09-20-2013, 10:20 AM
#47
Its not the same failure, the stab that failed in Kentucky fractured in the center. The material joining the two stab together was sub standard. Hard on the outside soft on the inside, like a sugar wafer cookie. I put a dremel tool with a drill bit through it like it was butter. That being said you have to wonder what came first, the flutter or the failure. I never got to see the remains of the Kentucky stab only the center piece that connects the two side together. This Hawk crash you can see where it failed in the pictures. I said before that they know they have problems, but the real problem is what there doing about it! Very sad to see another one go to the FEJ jet cemetery
09-20-2013, 10:32 AM
#50
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It's funny , I was the first victim of FEJ Hawk stabs breaking up in flight 4 years ago and I was promised a replacement jet 4 years ago to date nothing.
4 years later, the Hawk stabs are still breaking off in flight and you would think they did something to improve their design no?
I was told the stabs broke because of 3 things: 1- Elevator servo wires, 2-battery 3- linkage and yet the pictures and analysis of the broken structure showed that both broke in the same location at the same time. All this was provided to FEJ as proof. Besides many video and picture proofs have been submitted to FEJ. When will they wake-up? Do they need someone killed to fix the stab problem?
Enough is enough.
4 years later, the Hawk stabs are still breaking off in flight and you would think they did something to improve their design no?
I was told the stabs broke because of 3 things: 1- Elevator servo wires, 2-battery 3- linkage and yet the pictures and analysis of the broken structure showed that both broke in the same location at the same time. All this was provided to FEJ as proof. Besides many video and picture proofs have been submitted to FEJ. When will they wake-up? Do they need someone killed to fix the stab problem?
Enough is enough.