A couple of nice flights with the H9 Bluenose P51 on the weekend followed by one slightly heavy landing resulted in a broken wing spar. This is the second time and I have decided the last time in this configuration. The problem is these Arf's are poorly executed when it comes to construction. The wing has a surprising lack of plywood and soft balsa permeates the entire structure. After opening up my wing, I was shocked to see the soft Balsa spars, so rather than doing another poor repair that would ultimately fail, I instead decided to re-spar the wing. Here is how I tackled this problem. I opened up the bottom of the wing and located the breaks, I then proceeded to cut out the spar one rib bay at a time. Next I cleaned up the ribs to accept the new wood and then set the new spar into place. After the glue had set the wing was flipped upside down to do the top side. I have added additional shear webs and now I'm in the process of closing up the wing. Here are a couple of pictures to show the progress. I'll decide if the left wing requires the same treatment.
Glenn
Neat, you might have a weight imbalance if you don't do the left wing?
Maybe?
Jack.
Hey Jack,
I'm not sure the weight would be all that significant on this aircraft. But that being said, if it goes well I would do it just to know that the aircraft has both wings able to with stand a knock or two.
I'm just In the process of patching the openings now.
Cool! I would have never thought to do that, but it makes perfect sense. Great work!
Thanks Rob,
Sometimes all you can do is try and hope the results were worth the effort. Fortunately it seems to be working out.
Do you think the covering will iron back down O.K.?
It has worked before, but I may have to use another adhesive. Here is a picture of the top portion of the wing now ready for sanding. Most of the wing damage has been contained to the bottom wing.
Just a quick update, I flew the Blue nose twice yesterday. The wing is much more durable as is the landing gear. The first flight was great with the exception of too much down elevator when deploying flaps. The second flight saw a huge improvement in the slow landing speed due to both the neutral elevator and the wash out in the wing tips. Only down side was being unable to hit full power due to slight vibration. I believe the cause has been discovered and repaired. It turns out that the Firewall is also very weak and poorly built, but with good glue joints and additional plywood it should be as solid as the H9 Me109.
So now you know the weaknesses in the firewall Glenn, do you want to rebuild mine?!