Bugger!!

The carbon is way too short for the wing. I think 70-80% of the wingspan is the minimum.

Yup, I agree and Fergus obviously proved this first hand as well. I was actually surprised to see that the spar was this short. Hadn't thought about it before but when I see your cracked wing it's noticeable how short it is.

I've only flown homemade depron models which often are kind of delicate and brittle, although very lightweight and I've never used shorter lengths then 50% wingspan for the spars. Of course this all depends on what kind of wing you have. Since I've mostly made delta wings the wing loading is a lot less on the wingtips compared to a straight wing. For a straight wing I would go for at least 60-70% I think.

This is not a straight wing though and therein lies the problem. The two carbon spars end where the dihedral begins which given the rigid nature of eps results in this point being a huge area of stress.

I had seen this exact thing happen this plane on one of the Chinese forums. I thought the addition of the carbon strip I placed along the leading edge and the reinforcing with wbpu and stockings would be enough to counteract this but it was not enough.

The flexable nature of EPO might be enough to overcome this issue. I can't see how the carbon spars can be extended.

Regrards

Fergus.

Sorry to hear about your model Fergus. EPS really isn't a good material for RC planes. I had the Thunder Tiger Rare Bear miss my head by about 10 cm when I was trying to see how fast it would go on the second flight, when the polystyrene around the wing bolt cracked and the wing came off. A 250W motor swinging a 3 blade 9x6 prop at full throttle would not have been a pleasant experience to take full in the face.

The wing landed with no damage whatsoever, but the rest of the model exploded into about 100 pieces and I had to dig the motor out of the ground. That was the last EPS model that I will ever buy.

Originally Posted by Fergus

I can't see how the carbon spars can be extended.

This is a design fault and the manufacturer should fix it.

I'm sorry for your plane FERGUS, and thank you to share your experience with him.
the seller must do something for you!
may be that the aircraft E P O is better but I would not take the risk!

I found this one: http://abc-rc.pl/p/2/1168/model_tren...-samoloty.html

and talk about it here : https://www.rcgroups.com/forums/show....php?t=1226894

I think this plane is good, I ordered today

+ +

I am gutted for you Fergus.
All this effort... It does not look repairable

I am waiting for mine to come and it is the EPO version.
I wonder if there is an aero-dynamical reason for this violent pitch up. I wonder if it has something to do with the Location of the vertical stabiliser.
There might be some angles where the turbulence from the wing is blanking the stabiliser causing all sorts of misdemeanour's

I'll have to keep an eye on this. I will probably write my build in a new thread if that's OK with you.
I am a believer of "if it looks good it flies good " and this certainly looks good.

Originally Posted by Fergus

Sander,

Sorry man. That is almost identical to my flight. Did the plane pitch up prior to the wing snapping?

Whats your thoughts on the cause?

Regards

Fergus

Wingspar just came lose from the wing, taking with it chunks of foam. Despite the fact that I degreased (aceton) the foam prior to glueing and used CA on the Elapor (this was a Protech Voyager kit). Wasn't the first flight either, have done many flights like it, nor was it the first time I looped it'

Cheers,

Sander.

Fergus, this is bad news.

Please don't worry about airplane, I will send to you a new box EPO Skywalker as a gift.
You are our first Skywalker customer, I don't want to see you unhappy.

I hope your electronic equipments are as well.

I will send EMS Tracking number tomorrow.

Best regards.
FPVhobby team
Adnan.

Hi Zaguruinzasky.

I will send to you a new one EPO Skywalker airplane tomorrow also. This is best way for us. I will send EMS Tracking number tomorrow.

Best regards.
FPVhobby team
Adnan.

[QUOTE = FPVistanbul; 15018040] Fergus, ce sont de mauvaises nouvelles.

S'il vous plaît ne vous inquiétez pas pour l'avion, je vous enverrai une nouvelle boîte OEB Skywalker comme un cadeau
Vous êtes notre premier client Skywalker, je ne veux pas te voir malheureuse.

J'espère que vos équipements électroniques sont ainsi.

Je vais envoyer le numéro de suivi EMS de demain.

Meilleures salutations.
équipe FPVhobby
Adnan. [/ Quote]

Adnan,

the gesture is very good and professional and deserves to be said!
many vendors would not this thing!
thank you for fergus

Has any one got a epo version flying yet , or is the view that it is not a great design what ever the material ?

Originally Posted by FPVistanbul

Fergus, this is bad news.

Please don't worry about airplane, I will send to you a new box EPO Skywalker as a gift.
You are our first Skywalker customer, I don't want to see you unhappy.

I hope your electronic equipments are as well.

I will send EMS Tracking number tomorrow.

Best regards.
FPVhobby team
Adnan.

Well done Adnan!