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04-22-2013 | 10:08 AM

#25

Shaun Evans

Joined: Jan 2002

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From: San Diego, CA

RE: Another Fine Day With FEJ

Quote:

ORIGINAL: Aussie Bart

Dubd

I know your pain and some of your frustration. I too had the FEJ F14 although 1:8.75 scale fitted with 2 x P80's. It flew like a treat but every time I flew it I expected the wings to clap due to all the bad press on this forum however its final demise was my fault!

One day I was on a high speed pass low pass and could see the Stb fin banging side to side about 4 inches from 200 mts away, backed off the noise and dropped the gear and swung onto downwind to set up for landing. We could all still see the fin banging side to side when all of a sudden it departed the fuse when opposite us. The plane just kept flying as though there were no problems so I went through the normal landing procedure onto base and then onto final but I had let it get too slow and the inside wing stalled and she rolled in, total fuse loss but I had time to kill the donks so no fire.

First thoughts were bad flutter issues similar to B1 Bob and straight away started getting dark about FEJ, however some of the boys at the club had gone off and collected the fin while me and a few others were collecting the remains and what I found when the fin came back was a sombre reminder not to cut corners.<o

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>When I built it I decided to change the rudder control by fitting JR DS 168 thin wing servo's into each fin to get a more direct drive onto the rudder which I still believe is a better idea but I got slack and used the plastic servo arm that it came with. Well you guessed it, the servo arm was broken but the servo gears were just fine so the most likely cause of the failure was the arm snapped and the rudder just became an uncontrollable swinging mass.

Next day I went for a drive and held the fin outside the window into the airstream to see if the rudder would oscillate, even at a low speed of 30 kph, it became so violent that I struggled to hold onto it.<o

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>The other things I found on post crash examination were that the wing structure and wing box assembly were actually very strong and were not likely to fail. The amount of force caused by the oscillations was so big that the carbon rods in the fin had actually snapped with the remainder still in the intact clamps in the fuse. The first time I left plastic horns in a jet cost me a bucket of cash.<o

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>I also have a gen 1 1:6.5 FEJ A10 which was one of the very first out of the factory and I had issues with the wings. I had a lot of trouble with the factory trying to get them to review the design and was not the only one but eventually we sorted out the problems.<o

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>As I said earlier, I have experienced a wide selection of the mainstream manufacturers and keep coming back to FEJ simply because I like the big scale military stuff. I have just ordered the 1:4.6 F16 and like I always do, will go over it and modify area’s I personally feel are not right!<o

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>History is littered with these same stories but with different brand names, even BVM and the big Germans had serious issues and unhappy customers in the day, the only difference was there were no forums back then. These guys don’t have problems these days but they also don’t bring out any new planes. <o

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>I am truly sorry for your loss

Bart,

I think the position that the issues some of these Chinese ARF manufacturers are going through are the same 'growing pains' that manufacturers like BVM experienced is really a perfect example of a 'red herring.' For one thing, I've seen some airplanes (and I'm not singling out FEJ because it wasn't just them) where it was crystal clear that the people that made it never endeavored to try to assemble one themselves. BVM has never, ever done that. This new phenomenon of airplanes being sold that haven't been vetted by someone who knows about the science of physics and flight is new. The new 'norm' of having the end-user be the engineer, designer and test-pilot is new, too. If BV had an Ultra Bandit blow up in flight, that doesn't then mean that we can say, "Hey look, they ALL have this problem." Even a tested, well-engineered ship can fail for any number of reasons. The difference is that it's far less likely to fail.

Many of these ARFs are 'designed' on the TLAR principle (That Looks About Right) but get away with it for a while because it mostly works. When the clock runs out and either shoddy manufacture, poor QC or clueless design/engineering catch up to it...what happens then? Is a directive issued? Is a recall initiated? Is there an addendum or even a notice? That's the difference.

Based on what I've personally worked on for customers, some of these ARF's are nothing more than ticking time-bombs. The 'well mine flies great' defense is just silly as we all know that a broken clock is right twice a day. Also, why does it seem like the 'well mine flies great' people turn out to have at least one other bird from the same manufacturer that didn't fly so great? Again, this isn't leveled at FEJ alone. Frankly, to me, there is little difference between all these factories and their product.

These guys should have to put a disclaimer on the product that reads: "WARNING: This object has not been designed by anyone with demonstrable training or education in aeronautical or structural engineering. FURTHER: Neither this object, nor the materials it is composed of, have been exhaustively tested to root out design flaws and nothing has likely been subjected to any real quality control recognizable by accepted standards. FINALLY: The manufacturer neither expresses nor implies that any part or component of this object should be expected to do anything in particular at all. Fly at your own risk."

Now, that may sound sarcastic but if you think about it, it's honest. I've worked on or assembled jets from 4 different makes who I think need to stencil that on their box. You simply cannot say that about BV, JMP, JHH or Y/A's product (from a quality standpoint or a customer service standpoint).

If your rudder fluttered violently at 30 kts, you have a reason (and a moral/ethical responsibility if you ask me) to be suspicious and concerned about every other 'design' question on your airplane from the wheels on up.

What I don't get is why FEJ won't just STEP UP! Clearly, there's no shortage of modelers with actual training and education on this stuff. Why aren't they hiring a few of these guys to vet their models and then test them? Why not pay a real modeler to go over there and consult? The price of a round-trip ticket is around $1k. Add some room/board and ground transportation and an honorarium or stipend? Maybe it would cost them a bit up front, but with as pretty as their planes are and with as many new models they come out with every half hour, wouldn't it be cost-effective in the end if the US market could trust their product?? I don't get it...

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