Bob Cat Copy Falcon 120 Jet
07-20-2008, 02:15 PM
#1376
RE: Bob Cat Copy Falcon 120 Jet
yea, sorry for your loss.[:@]
Just strange, but if you look at the videos on youtube, the falcon is flown pretty hard.......but who knows wwhat they have done to strengthen it.
Just strange, but if you look at the videos on youtube, the falcon is flown pretty hard.......but who knows wwhat they have done to strengthen it.
07-20-2008, 02:43 PM
#1378
RE: Bob Cat Copy Falcon 120 Jet
ORIGINAL: TUMBLER
WHAT A PIECE OF JUNK!!
Wow, is all I can say. What a wastes of time and money this thing was. I started when I was 12 and have 19 years of flying and have never been so disappointed in a plane.
Here is what happened. I took off on her 4th flight and cruised around at half throttle the entire time. I had been scared to open her up, so just flew her gently at half throttle doing slow rolls, a loop, and some inverted flight. After 5 minutes the timer went off, so I put in the first notch of throttle. No problems yet. Then I went to full flaps to test out the crow mix I wanted to try on this flight. It didn't feel dialed in right so I went back to half flap. THAT"S WHEN ALL HE BROKE LOOSE! As soon as I went from full flap to half, it pitched up into a wall, the wing tube folded, and blew up the left wing. Remember.....this is all at just above IDLE!! I shut off the motor and it fell like a paper airplane striaght down and luckily did not damange anyof the importat parts.
Lesson learned.....do not put $3-4,000 worth of electronics and trurbine into a cheap knock off airframe!
Tumbler
WHAT A PIECE OF JUNK!!
Wow, is all I can say. What a wastes of time and money this thing was. I started when I was 12 and have 19 years of flying and have never been so disappointed in a plane.
Here is what happened. I took off on her 4th flight and cruised around at half throttle the entire time. I had been scared to open her up, so just flew her gently at half throttle doing slow rolls, a loop, and some inverted flight. After 5 minutes the timer went off, so I put in the first notch of throttle. No problems yet. Then I went to full flaps to test out the crow mix I wanted to try on this flight. It didn't feel dialed in right so I went back to half flap. THAT"S WHEN ALL HE BROKE LOOSE! As soon as I went from full flap to half, it pitched up into a wall, the wing tube folded, and blew up the left wing. Remember.....this is all at just above IDLE!! I shut off the motor and it fell like a paper airplane striaght down and luckily did not damange anyof the importat parts.
Lesson learned.....do not put $3-4,000 worth of electronics and trurbine into a cheap knock off airframe!
Tumbler
Dave
07-20-2008, 02:53 PM
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RE: Bob Cat Copy Falcon 120 Jet
Yes, I repaired the wing and strengthened the other one just in case. I have a Ram 750 with 18lbs, just like many other guys flying with Wren Supersports on 18lbs. I have never even gottem above half throttle on mine though. Reagardless it failed at idle getting ready to land.
07-20-2008, 03:04 PM
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RE: Bob Cat Copy Falcon 120 Jet
Tumbler, I haven't flown mine yet, it's still under slow construction, but it appears to be an acceptable design that is being enjoyed by many. I gotta believe that airframe was abused by either the craftsman, or the pilot, or both. Sorry, but with all due respect, I don't think that you helped your skills reputation any by making a statement like that.
... zak
... zak
07-20-2008, 03:25 PM
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RE: Bob Cat Copy Falcon 120 Jet
Trust me I am not worried about that at all. I have done the demo videos for a lot manufactures and definetly know how to fly an airplane within its limits. Go over to rcgroups.com and see some of the videos I have done as well as the NUMEROUS build threads. I know how to fly and know how to build! This plane simply failed. I was trying to worn those who are thinking of buying them, as well as those who have bought them. If it were me I would want to know, so I could take precautions and possibly prevent this from happening to me.
You must be some kind of moron coming on here and trying to accuse me of abusing the airframe and ruining my reputation. Hopefully yours will work out great for you, but others may want to see that the airframes can fail. My gear ripped out on what no one thought was a rough landing and now the wing tube bent while at idle. What would you think???
You must be some kind of moron coming on here and trying to accuse me of abusing the airframe and ruining my reputation. Hopefully yours will work out great for you, but others may want to see that the airframes can fail. My gear ripped out on what no one thought was a rough landing and now the wing tube bent while at idle. What would you think???
07-20-2008, 03:47 PM
#1382
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RE: Bob Cat Copy Falcon 120 Jet
sorry for you loss. Wonder if there was "hidden" damage done when the gear got ripped out. I have ripped the gear out once, but I put new wings on from another kit. I have dove this jet full bore going straight down, pulled out and have never noticed anything.
As for the quality control, you are right...there is none. That is why these kits need to be hacked on to get them turbine ready.
However, don't forget that these are not the only ones without problems. Some of the major mfg. (not going to say which ones as it will prob. get the thread closed) have had issues and failures as well.
Tumbler again sorry for you loss. That stinks. Wish we knew exactly what failed first or what happend. Maybe there is a hidden flaw inside the wing just waiting to bite us.
As for the quality control, you are right...there is none. That is why these kits need to be hacked on to get them turbine ready.
However, don't forget that these are not the only ones without problems. Some of the major mfg. (not going to say which ones as it will prob. get the thread closed) have had issues and failures as well.
Tumbler again sorry for you loss. That stinks. Wish we knew exactly what failed first or what happend. Maybe there is a hidden flaw inside the wing just waiting to bite us.
07-20-2008, 03:55 PM
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RE: Bob Cat Copy Falcon 120 Jet
Thanks Noah. I did consider that, however when the gear came out, it was not a very traumatic event. In fact, we just thought the gear collapsed and were shocked to find that it had ripped out. It was just about stalled coming in for a perfect landing, but was a little sideways because of the crooswind, which is what did it. It did not tumble or do anything crazy. The wing itself seemed strong enough to handle 18lbs of thrust but would never dive it down at full throttle or do full throttle turns. Nevertheless, the wing held up. It was the wing tube that failed.
ORIGINAL: noahb
sorry for you loss. Wonder if there was "hidden" damage done when the gear got ripped out. I have ripped the gear out once, but I put new wings on from another kit. I have dove this jet full bore going straight down, pulled out and have never noticed anything.
As for the quality control, you are right...there is none. That is why these kits need to be hacked on to get them turbine ready.
However, don't forget that these are not the only ones without problems. Some of the major mfg. (not going to say which ones as it will prob. get the thread closed) have had issues and failures as well.
Tumbler again sorry for you loss. That stinks. Wish we knew exactly what failed first or what happend. Maybe there is a hidden flaw inside the wing just waiting to bite us.
sorry for you loss. Wonder if there was "hidden" damage done when the gear got ripped out. I have ripped the gear out once, but I put new wings on from another kit. I have dove this jet full bore going straight down, pulled out and have never noticed anything.
As for the quality control, you are right...there is none. That is why these kits need to be hacked on to get them turbine ready.
However, don't forget that these are not the only ones without problems. Some of the major mfg. (not going to say which ones as it will prob. get the thread closed) have had issues and failures as well.
Tumbler again sorry for you loss. That stinks. Wish we knew exactly what failed first or what happend. Maybe there is a hidden flaw inside the wing just waiting to bite us.
07-20-2008, 04:05 PM
#1384
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RE: Bob Cat Copy Falcon 120 Jet
Think I may have to go into mine now and check it out. I do have a carbon wing tube that came out of another airplane that is the same size. It came from a Fliton Inspire (sp?).
I know that when I put these wings together, that I dripped a lot of gorrila type glue down into the wings, spars, webbing, blocks, just about anywhere I could get the glue to.
I am going to remove the bottom off my old set of wings and take some pictures. Maybe there is something there.
as for the alum tube, that has always worried me. Plus, the whole wings is held on by four screws secured to just the outer root. If the outer root pulled away just a little bit, this would allow the wing to flex a lot.
I will post some pictures in a day or two of my old wings. Let people see how they built them. Maybe if we get a lot of people looking, might come up with a good strong fix.
I know that when I put these wings together, that I dripped a lot of gorrila type glue down into the wings, spars, webbing, blocks, just about anywhere I could get the glue to.
I am going to remove the bottom off my old set of wings and take some pictures. Maybe there is something there.
as for the alum tube, that has always worried me. Plus, the whole wings is held on by four screws secured to just the outer root. If the outer root pulled away just a little bit, this would allow the wing to flex a lot.
I will post some pictures in a day or two of my old wings. Let people see how they built them. Maybe if we get a lot of people looking, might come up with a good strong fix.
07-20-2008, 04:27 PM
#1386
RE: Bob Cat Copy Falcon 120 Jet
Wow,, I didnt even start the build and I'm freaked out now,,, I think I'm going to open up the bottom of the wings and hysol everything,, also after seeing what happend to Tumbler,, I think I'm going to see if I can find a carbon fibre wing tube.
07-20-2008, 05:35 PM
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RE: Bob Cat Copy Falcon 120 Jet
I dont think that simply the flap retraction could have caused a pitch that violent. At less than 50mph, it would have to be really abrupt to bend that wing tube unless your plane is 20+lbs. I do spins, and snaps at those speeds and 50 flights later, I dont have any problems.
You must have had some sort major flight control malfunction. Sorry about the loss and glad the expensive parts survived.
Maybe you were just unfortunate enough to get one with some problems. I think there are too many out there being enjoyed to labeled as "junk", maybe yours was for whatever reason. I couldnt be happier with mine and for those who are starting to build one now, I have 2 new ones in the box and I wouldnt part with either of them.
cody
You must have had some sort major flight control malfunction. Sorry about the loss and glad the expensive parts survived.
Maybe you were just unfortunate enough to get one with some problems. I think there are too many out there being enjoyed to labeled as "junk", maybe yours was for whatever reason. I couldnt be happier with mine and for those who are starting to build one now, I have 2 new ones in the box and I wouldnt part with either of them.
cody
07-20-2008, 05:38 PM
#1388
RE: Bob Cat Copy Falcon 120 Jet
Grodus,, what Turbine are you flying yours with? I picked up a P60 SE for mine,,,also do you think it would be worth putting a carbon tube instead of the Alum.
07-20-2008, 05:53 PM
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RE: Bob Cat Copy Falcon 120 Jet
I don't think the flap retraction caused it eaither. I think it was coincidental. The root rips are still attached to the fuse with the 4 bolts sheered off, so the wing did not come loose. Usually when a wing tube bends it tears up the fuse, but mine is 100% in tact. It just makes me think the wing tube was low grade. Mine has mishapen wingtips which are down 1/8" on one side and up 1/8" on the other side, very low grade ply in the retract area, and a weak wing tube. To me, the one I got was junk. Looked good after a lot of work, but still not as strong as they should be for turbines imo.
ORIGINAL: Grodus
I dont think that simply the flap retraction could have caused a pitch that violent. At less than 50mph, it would have to be really abrupt to bend that wing tube unless your plane is 20+lbs. I do spins, and snaps at those speeds and 50 flights later, I dont have any problems.
You must have had some sort major flight control malfunction. Sorry about the loss and glad the expensive parts survived.
Maybe you were just unfortunate enough to get one with some problems. I think there are too many out there being enjoyed to labeled as "junk", maybe yours was for whatever reason. I couldnt be happier with mine and for those who are starting to build one now, I have 2 new ones in the box and I wouldnt part with either of them.
cody
I dont think that simply the flap retraction could have caused a pitch that violent. At less than 50mph, it would have to be really abrupt to bend that wing tube unless your plane is 20+lbs. I do spins, and snaps at those speeds and 50 flights later, I dont have any problems.
You must have had some sort major flight control malfunction. Sorry about the loss and glad the expensive parts survived.
Maybe you were just unfortunate enough to get one with some problems. I think there are too many out there being enjoyed to labeled as "junk", maybe yours was for whatever reason. I couldnt be happier with mine and for those who are starting to build one now, I have 2 new ones in the box and I wouldnt part with either of them.
cody
07-20-2008, 05:55 PM
#1390
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RE: Bob Cat Copy Falcon 120 Jet
If you can find a carbon tube, I would go with it. If not, I would not worry about it to much. I would drip a polyurethane or other good glue into the wings. I put it on ribs, blocks, spars, leading edge, webbing, etc... Keep in mind they use crappy glue and this may have been what happend to Tumblers wing. I wonder if his wing started to fail and then this caused the tube to bend.
If you guys that are still building and are worried about it, then open up the bottom of the wing in a few spots and apply some epoxy to the spar, webbings, stuff like that.
I have a carbon tube that fits, it came from a crashed Fliton Inspire. Not sure where you can get one, but hope it helps. It actually is longer then the alum tube.
If you guys that are still building and are worried about it, then open up the bottom of the wing in a few spots and apply some epoxy to the spar, webbings, stuff like that.
I have a carbon tube that fits, it came from a crashed Fliton Inspire. Not sure where you can get one, but hope it helps. It actually is longer then the alum tube.
07-20-2008, 06:03 PM
#1391
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RE: Bob Cat Copy Falcon 120 Jet
Even high end planes like BVM can sometimes fail, usually when they are overpowered and put through too many G's. Considering mine failed at just over idle for some fluky reason though, I would think it better safe than sorry on the Falcon and strengthen the tube. Just trying to prevent it from happening to someone else.
Tumbler
Tumbler
07-20-2008, 06:10 PM
#1392
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RE: Bob Cat Copy Falcon 120 Jet
Tumbler, I agree with you.
I even applied some thin g-10 material to the inside of the booms. This g-10 came down into the wing and went down past the wing tube. I marked where the wing tube was to go thru it, cut that out and now if the little blocks fail on the booms, the wing tube is still capturing the g-10 material which is epoxied to the booms.
Just glad your stuff is ok and nobody got hurt.
I even applied some thin g-10 material to the inside of the booms. This g-10 came down into the wing and went down past the wing tube. I marked where the wing tube was to go thru it, cut that out and now if the little blocks fail on the booms, the wing tube is still capturing the g-10 material which is epoxied to the booms.
Just glad your stuff is ok and nobody got hurt.
07-20-2008, 06:13 PM
#1393
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RE: Bob Cat Copy Falcon 120 Jet
Sounds like you did a lot to strengthen it. Thanks, I'll just have to find an airframe now.
ORIGINAL: noahb
Tumbler, I agree with you.
I even applied some thin g-10 material to the inside of the booms. This g-10 came down into the wing and went down past the wing tube. I marked where the wing tube was to go thru it, cut that out and now if the little blocks fail on the booms, the wing tube is still capturing the g-10 material which is epoxied to the booms.
Just glad your stuff is ok and nobody got hurt.
Tumbler, I agree with you.
I even applied some thin g-10 material to the inside of the booms. This g-10 came down into the wing and went down past the wing tube. I marked where the wing tube was to go thru it, cut that out and now if the little blocks fail on the booms, the wing tube is still capturing the g-10 material which is epoxied to the booms.
Just glad your stuff is ok and nobody got hurt.
07-20-2008, 06:23 PM
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RE: Bob Cat Copy Falcon 120 Jet
Hi tumbler, sorry about the loss of your model, do you think that the cause of the crash was the ally wing tubes failing, or failure of the wing structure itself.? Did the bending up of both sides of the tubes, occur in flight or as a result of the plane hitting the ground, as the remaining wing appears mostly in tact. Have you any video of the incident? There are a lot of planes flying out there and all this info helps in providing a safer plane for us all. I have a carbon main spar and ally front spar, purly to reduce weight, as I am heavier than a comercial bought engine installation. My wings only have 1 bolt retaining fixure in the root of the wing, I think you have 2. I have read somewhere that the later versions have a few differences, like 2 bolts in the wings, is the the rest of wing the same as the old version.
My beast has had 59 flights, all but 3 take offs have been on rough grass and the structure has performed well. (Note my previous post ref cracking around the engine mount area)
Anyone who has posted video on youtube, can you include some info on any strengthening measures you took, or any change to the spars you may have made and if the models are still airworthy. Some of the videos show the plane in high G manouvers. I would agree that any quality stamp you may find on the structure of the kit may not represent inspection levels that you or I would consider to be adaquete. I have made no strengthening measures on my wings.
I have read an alert somewhere, reference another model, having problems with the wood sheeting that makes up the main spar, having its grain running in the wrong direction which could cause structural failure in flight, (not this model, but you never know). It might be worth a look at yours so see if there are any anomolies in this area.
I would say that I, like many others, are really pleased with the model and I have not experieneced this type of failing of the structure, despite a few heavy and occasionally really heavy landings, bearing in mind i have carbon main spar.
Glad your main expensive items survived, hope you get airbourne again and would like to say that it was such a shame to see a really well finished model let you down, all best Tim
My beast has had 59 flights, all but 3 take offs have been on rough grass and the structure has performed well. (Note my previous post ref cracking around the engine mount area)
Anyone who has posted video on youtube, can you include some info on any strengthening measures you took, or any change to the spars you may have made and if the models are still airworthy. Some of the videos show the plane in high G manouvers. I would agree that any quality stamp you may find on the structure of the kit may not represent inspection levels that you or I would consider to be adaquete. I have made no strengthening measures on my wings.
I have read an alert somewhere, reference another model, having problems with the wood sheeting that makes up the main spar, having its grain running in the wrong direction which could cause structural failure in flight, (not this model, but you never know). It might be worth a look at yours so see if there are any anomolies in this area.
I would say that I, like many others, are really pleased with the model and I have not experieneced this type of failing of the structure, despite a few heavy and occasionally really heavy landings, bearing in mind i have carbon main spar.
Glad your main expensive items survived, hope you get airbourne again and would like to say that it was such a shame to see a really well finished model let you down, all best Tim
07-20-2008, 06:47 PM
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RE: Bob Cat Copy Falcon 120 Jet
ORIGINAL: airspeed917
Grodus,, what Turbine are you flying yours with? I picked up a P60 SE for mine,,,also do you think it would be worth putting a carbon tube instead of the Alum.
Grodus,, what Turbine are you flying yours with? I picked up a P60 SE for mine,,,also do you think it would be worth putting a carbon tube instead of the Alum.
Airspeed,
I used the stock aluminum tube. The only thing I did was fill the channels on the underside of the booms with 1/2" balsa and then hysoled the booms to the wings and used 1/4 nylon bolts.
This kit was purchased a year ago. The tubes on the new kits are different. They are chrome plated but I think they are still aluminum.
I have a 14lb Superbee on mine. 14.5 lbs with a full Uat.
Cody
07-20-2008, 06:48 PM
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RE: Bob Cat Copy Falcon 120 Jet
Well, it's time for me to go shopping for servo extensions. Did anyone keep a record of the lengths that they used in the booms, and the wings ?
Lengths and numbers would be greatly appreciated.
Thank you.
... zak
Lengths and numbers would be greatly appreciated.
Thank you.
... zak
07-20-2008, 09:54 PM
#1398
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RE: Bob Cat Copy Falcon 120 Jet
OK Zak,
Here are the extensions I used. You can use this as a guide but I must caution you, yours may not come out exactly the same. Look over your application carefully and take some measurements. The extensions you need will depend on: how many channels you use, what mixes you use, how you route the extensions, the location of your receiver, and how long the leads are on your servos.
In Booms/ In Wings/ In Fuse
Rudders/ (2) 12"/ (2) 18"/ (1) 12" Y
Elevator/ (2) 24"/ (2) 18"/ (1) 12" Y one elevator servo is reversed
Ailerons/ -/ (2) 12"/ (2) 18"
Flaps/ -/ (2) 6"/ (2) 18"
Steering/ -/ -/ (1) 12"
This allows me to have connections at each interface (boom/wing and wing/fuse).
Joe
Here are the extensions I used. You can use this as a guide but I must caution you, yours may not come out exactly the same. Look over your application carefully and take some measurements. The extensions you need will depend on: how many channels you use, what mixes you use, how you route the extensions, the location of your receiver, and how long the leads are on your servos.
In Booms/ In Wings/ In Fuse
Rudders/ (2) 12"/ (2) 18"/ (1) 12" Y
Elevator/ (2) 24"/ (2) 18"/ (1) 12" Y one elevator servo is reversed
Ailerons/ -/ (2) 12"/ (2) 18"
Flaps/ -/ (2) 6"/ (2) 18"
Steering/ -/ -/ (1) 12"
This allows me to have connections at each interface (boom/wing and wing/fuse).
Joe
07-20-2008, 10:02 PM
#1400
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RE: Bob Cat Copy Falcon 120 Jet
Something to note about Tumbler's mishap.
The plane was designed to be a pusher. If he was truly at idle or even half throttle then a pusher glow would have been even more stress on the airframe (not to mention the vibration). So it had to be a design flaw or the tube was weakend from previous flight(s) and he didn't notice.
We all know the risk at $209 for a turbine trainer jet that isn't built for turbines and is a low end Chinese model. I'll beef mine up the best I can and fly the piss out of it.
Sorry for your loss Tumbler.
The plane was designed to be a pusher. If he was truly at idle or even half throttle then a pusher glow would have been even more stress on the airframe (not to mention the vibration). So it had to be a design flaw or the tube was weakend from previous flight(s) and he didn't notice.
We all know the risk at $209 for a turbine trainer jet that isn't built for turbines and is a low end Chinese model. I'll beef mine up the best I can and fly the piss out of it.
Sorry for your loss Tumbler.