CL-415 group-build thread

electroflyer · May 06, 2019, 08:48:05 PM

Thanks guys,
Yesterday was great fun, we were able to get both CL's flying with normal teething pains, but they survived and looked pretty cool. Here is Michael coming in for a super smooth landing.

piker · May 07, 2019, 10:04:31 AM

Congrats, guys! I'm glad they fly as expected, and look so cool.

I just realized that whenever we see the water bombers on the news, there's always three or four in line cycling through the water pickup and drops. The 3 to 5 models flying together will recreate that awesome dance perfectly!

My 215 will represent the old school version of the full size as well as old school in model form

It'll be 22 years old this summer

Michael · May 11, 2019, 06:44:25 PM

I added a few ounces of weight in the nose, and it flew much better, but still climbed with power.

The elevator had a lot of down trim just so the plane could fly level, likely due to the very substantial positive wing incidence (forward wing tiled up too much).

After several discussions with Glenn, who is experiencing similar challenges, we came up with a simple solution (we hope).

I built a small structure to reduce the wing incidence, (a quarter-inch higher at the back where the wing sits on the fuselage, so the wing is not tilted up so much)) and will likely need less down trim, and the plane probably won't climb so much with power with the new wing-stabilizer set-up.

The photos should be self-explanatory.

electroflyer · May 14, 2019, 10:44:45 AM

As Michael mentioned above, the CL415 we built has an incidence that always appeared to be too extreme. The first flight all but proved this. My model was balanced on the c of g and immediately upon take off started to climb at an extreme rate. I added down trim and throttled back, this stabilized the aircraft, but whenever I throttled up the pitch angle would change radically. The landing occurred without incident, but the model required changes to be a fun flyer at faster speeds. I added nose weight to mine which I thought would solve the problem, but after watching Michael fly his successfully on several occasions, I thought he had licked the problem. Upon discussion though, he acknowledged that he felt that it was still not right. After checking his plane, the radical down trim proved that the CL was not quite right. I told Michael that I was going to trim my wing saddle down by a quarter of an inch at the leading edge which I felt would bring the main wing into better alignment. Michael chose to lift the trailing edge by a quarter inch (accomplishes the same thing). I actually trimmed the saddle down to 3/16" but have a little space left to continue should it be required. The aircraft actually looks much better sitting on the stand. I am now looking forward to the next flight!

Michael · May 18, 2019, 05:41:20 PM

What a difference!

The plane has just had its' 5th and 6th flights, and with the modification, it flew superbly!

octagon · May 27, 2019, 09:03:11 PM

Ouch!

sihinch · May 27, 2019, 09:10:14 PM

Oh no, Rob. I'm so sorry.

Do you know what happened?

Michael · May 27, 2019, 09:46:27 PM

Is it repairable?

battlestu · May 28, 2019, 08:18:37 AM

ouch very sorry to see that

Oscar · May 28, 2019, 08:26:44 AM

So sorry to see that. Did you find out what happen?

octagon · May 28, 2019, 08:59:51 AM

We flew the plane on Sunday and it veered to the left so bad it took all the rudder and aileron trim, and after takeoff I passed the transmitter to Glenn, all his skill just to get the thing back down in once piece. I took note of the deflection of the flying surfaces, centred the trims and then mechanically put them back to what they had been when it landed. This should have, in my mind, made it fly relatively strait. Yesterday, I took off and at first all was good, it climbed out well and had lots of power. Then, when I tried to turn east (took off going north) nothing happened. Full right aileron and it just flew strait on going north. In fact it started to turn west, even with full right aileron. I decided to circle west and try and come back over the field, hopefully going above the trees on the western barrier of the field. Glenn and BJ were yelling for me to pull up, and God help me I was holding full up but it would not climb. It missed the first clump of trees, but there is a big dead bunch and it shredded itself through them. The right wing from just past the nacelle was sheared off, and the wing bolts gave way so the fuselage continued on crashing nose first onto the field north of pilot stands, in the farmers area. The plane is beyond repair.
The question of why the plane was not controlable will haunt me for a long time. I found that the left aileron servo and the elevator servo were both stripped, but whether that happened on impact of it they contributed to the loss I will never know. I did notice that the vertical stab was not exactly strait, but I figured rudder trim would overcome this, and it did the day before. I know as pilots we have to take these things in stride. Crashing is part of the sport and is one of the aspects that makes it exciting, because we all know that there is a possibility on every flight, we might end up with little pieces of plane. But this one is harder than some. The kit was a bit of a bitch to build with sketchy plans, and took about 5 months to complete. I really came to like the look of the plane and I wish I could have saved it.

bweaver · May 28, 2019, 09:23:24 AM

Re: "I wish I could have saved it."

So do we.

sihinch · May 28, 2019, 09:36:04 AM

Hey Rob, I really do feel your disappointment and frustration. And I know that you know it is part of the hobby.

For my last few crashes I have tried to focus on the fun and enjoyment that I got from building or painting the plane, despite crashing it. So maybe in a few days, you can look back on the 5 months of enjoyment and challenge you got from building it, despite the crash.

I know it is still a bugger though!

I'm sorry.

piker · May 28, 2019, 02:02:24 PM

Oh man! That sucks. I'm sorry for the crash. Crap!

I know it looks like a total loss to you right now, but I can tell you from experience that there's a lot of good parts there and with a little bit of piecing back together it's start looking like new again. Think of the time it would take you to rebuild all those good parts compared to piecing the bits back together or even rebuilding part, like the right wing. It's DEFINITLY repairable and WELL worth the little bit of effort.

Robert

octagon · May 28, 2019, 03:49:05 PM

Thanks for the words of encouragement, but I don't think the picture I posted really does not show the extent of the damage Rob. What is left of the hull is spread open like a big pea pod. the sheared off wing is just a mess, plywood spars fractured, sheeting a mess. The tail and elevators are pretty much intact. Honestly, with the experience of building this one, I think it would be faster to just build a whole new one. I might do that next winter, but I will wait and see how Glenn and Michael make out. We feel the plan is fundamentally flawed in that as per the plans the plane has 4 degrees of positive incidence and the GC is way off too. We all had to change that by about 1/4 of an inch. But quite honestly, right now I have put everything in a box and am waiting for the plane to fix itself. I know this happens because Frank VB says so.