Way2High

Has anyone built an allegro here? I am relatively new to flying sailplanes but I have been building free flight models from balsa for quite some time now. I started with a Gentle Lady about 2 years ago and have rekitted the first one until it didn't seem reasonable to fix it so I bought another kit and have rekitted it a few times now as well. Maybe I should have found someone to help me get it up in the air but trial and error has worked. It is still in good shape but I am planning to build the allegro with foam core wings. The main reason I am asking about it is, I built a v tail pod and boom glider with a set of sky glider wings covered with glass with ailerons. It flew but not as well as I had hoped. I don't want to spend much time on the Allegro if it doesn't fly at least as well as my gentle lady.

Jack Hyde

My Feedback: (1)

There is tons of Allegro info on the Allegro forum. Do a Google search - Allegro lite - and you will find the URL. I hear that Allegos fly much better than Gentle Ladies.

soarer

My Feedback: (1)

If you want foam cores cut for the Allegro check out CNCFoam.com. I think that there is a yahoo group forming to discuss designing and building different sailplanes and they might consider looking into the Allegro.

Good luck
Chris

Way2High

I have a hot wire cutter and have gotten pretty good at cutting out the foam cores. It seems to be much quicker than building up with balsa. I tried cutting out some freehand templates and put these wings on a pod and boom v tail that I built, but it still doesn't fly as well as my gentle lady. I was thinking of building up one of mark's designs from the charles river site. I think he knows more about airfoils than my freehand method will ever be. I finished the templates for his airfoil last night and I will cut some cores tonight. I don't know if I am going to go though all the truble to winch proof the spars since all I have ever used is a high start and my arm and I will probably eat the wings up long before I find someone with a winch. I hope this bird will fly better than what I have tried on my own so far.

fprintf

Way2High:

When you say the pod and boom you have doesn't fly as well as the Gentle Lady, did I read that you "freehanded" the airfoils? Like as in eyeball a template and hope for the best? Or did you use some kind of airfoil coordinates - just weren't picky about the airfoil?

If you used a modern airfoil could it be how you are flying it?

I am new at this sailplane thing but I do know that depending on the airfoil, you may have to fly *much* faster than the Gentle Lady to get an adequate glide ratio. I am sure others can chime in with the technical reasons.

For instance, even on my Highlander sailplane, the guys teaching me saw me flying just above stall speed - which is good for a floater like the Gentle Lady. They had me trim it down so that it flew perhaps twice as fast -- and I did not come down nearly as quickly. It was much harder to put into a thermal circle at that speed, but stayed up quite a bit longer. I think the new generation of airfoils likes to be flown much faster than the old ones.

As for Winch proofing the wing, just make sure it is strong enough to take even a highstart launch. How are you planning to cover the foam? Balsa? Obeechi?? Poplar? etc.? Are you going to use a spar?

The reason I ask is that I am currently building a Terminator handlaunch (getting cores cut this weekend if my cutting technique comes together a bit better) and plan on just covering the foam with Balsa without any spar. That wing will take an upstart, certainly not my highstart.

Stuart

p.s. I am using a software called "profile" to generate my templates from .dat files found on the Internet and it works like a charm! Free too!

Way2High

The cores I used on the pod and boom I built were from the sky glider that you buy at Wal Mart. They were only 48" so I copied the outer airfoil and cut some extensions. It ended up being 72" and weighed 18 oz. I put in a basswood spar and put trailing edges on it out of balsa. I made the wing flat and put ailerons on it and covered it with 2 ounce glass. I tried a lot of different airspeeds with it and it flew good but its l/d ratio was pitiful. It liked to fly about 2.5 times faster than my GL.

I cut the cores for the allegro this weekend. I put on a balsa trailing edge and put in a dowel for the spar. I made the wing a little longer than what it is supposed to be. The wing will end up being 94" instead of 78". I know I should have made it the way they show but I always have to try something different. I made it a three piece wing because of it's size. I plan to cover it with glass. I sure hope this works.