BrianB

My Feedback: (2)

Hey everyone, I am currently morning the loss of my brand new 3W 31% g-202. It was completed this last week after 6 months of building and finishing. It only lasted 30 sec of first flight before right side wing snaped in half and the plane went in. The plane took off as pretty as could be and i climbed to safe altitude and was cruising at half throtal starting to trim her out, did a slow bank to the left and half way through the turn it happend. The outer half of right wing pannel left the plane and was 300 feet from crash site. Opon post crash inspection the wing had broke right where the servo bay was installed { outer edge of servo bay box } the foam in these wings is not very dense { the foam balls that the foam consist of is approx. 1/4 inch in dia. } most foam in cored wings I see is of much denser consistancy. Also the sheeting on the wing in the area of the break was sanded to a thickness of less than a 32nd of an inch and prob. more like a 64th of an inch. So in this area of the wing there was nothing but foam and a very thin layer of sheeting, no spar just foam and paper thin sheeting with large opening for servo bay cut in. The left wing has a small crack in the sheeting in the exact same area and would have failed as well. needless to say I am very dissapointed at this point and am wondering if anyone else has had this problem. This was not a cheep kit and I would have exspected better results. I have not been able to contact Aircraft Int. yet but they have always given great service to me with all the engines I have purchased and do not expect anything but the same with this. Any input from this forum would be great.
The plane details are as follows:
31% G-202 with 83 inch span
kit is an arc, all sheeting is complete, just needed covering and assem.
3w 50i engine
Jr Digitals on all surfaces
rocket city horns
darrel cady cf control rods
air wild arms
klett hinges and all surfaces sealed
18lbs dry


Ok this is what 3W had to say, 3w claims that because the sheeting on the wings was wood peckerd before covering the wing sheeting failed. After reading many articles on this subject I realize that this may not be the smartest way of acheiving good covering on sheeted wings but I starting using this method after reading a coloum in rcm or model aviation where a well known pilot/building descriped this method. The method is as follows. Mix elmars white glue and water 50/50 and apply with brush then wipe with paper towel to avoid getting sheeting soaked, a thin coat is all that is needed. Let dry and wood pecker entire surface. Next sand with 600 just until wood pecker holes fill and disapere { this is not much } blow clean with compressed air and prep for covering.
I have used this method on twelve sets of wings and have never had a problem. My side of this is that the sheeting that was this wing was very thin { 1/32 at best } as stated above in the original post, It had no spar and poor quality foam { in my opinion } It did have a layer of fg cloth that extended out about half the length of the wing in a triangle shape and ended just before the point where it failed. I will no longer use this method BUT I think this wing was not fit for a 18lb 3D type plane. Any input would be greatly appreciated as I am very dissapointed and 3w is going to not do anything for me. I do not want a free ride if in fact this is my fault but I lack in the knowledge to say one way or another. I have done ALOT of reading on sheeting and making foam core wings since this happened and have have to the conclusion that this wing needs a spar to be up to the task that this type of plane will demand.

Thanks in advance Brian B

Davis

Brian:

I sure understand how you feel. I have had expensive airplanes destroyed on first flights also. It is not only the time, which can never be replaced, and the money.
Please let us know the outcome of this.

Davis

BrianB

My Feedback: (2)

Spoke with Aircraft Int. and they want to see the wings. I boxed them up this morning and will ship them today. Aircraft Int. has been very helpful so far and I don't expect any problems but I will get everyone informed. Thanks for the only reply Davis.

Barts

I just purchased a level 3 31% giles from Gerhard at aircraft international. I am planning on putting a zdz 60 on it. Please inform me on what you hear. They are very expensive planes.

Thanks

BrianB

My Feedback: (2)

I have posted my reply from 3w in original post above.

BP5589

My Feedback: (4)

Brian, sorry for your loss. I find it odd that a plane of that size would not have a spar, foam and light cloth just doesn't seem to provide enough integral strength. I could be wrong but I have seen other foam wings with spars built into them on much smaller planes.
Good Luck,
Bill

BrianB

My Feedback: (2)

Thanks for your support Bill, Bill the FG cloth does not even span the whole wing, from the inboard side of the servo bay to the tip is nothing but foam and thin sheeting. The cells that the foam is comprised of are very large { 1/4'' dia. } and is very different from the smaller cells most foam I see is made of.

I need to hear more opinions from pro builders that are on this site. Good or bad I want to hear. I need all opinions to decide where I go from here.

Thanks Brian