ASW-22 - 7.2 meter

[Gudmund]

Gentlemen,

I finally finished and flew my last real build project - a Yellow Aircraft F-16 powered by a 100mm EDF on 11 cells. The project took two years to complete, during which I "assembled" a 3.2-meter Pulsar and a 2.5-meter Cumulus (both specifically designed for Altitude Limited Electric Soaring use). It is time to do something different.

My biggest scale sailplane is a 6-meter Ventus 2cx that I love to fly - two weekends ago, my friends demanded that I land after a 1-hour flight so we could all go for some french fries.

I have always thought I needed something even bigger and an opportunity to acquire the foam cores and Rosenthall fuselage for 7.2-meter ASW-22 could not be resisted. I even discovered that I have (acquired at a club auction many years ago - but never opened) a box with five sheets of 30cm x 3.4m obechi. Are the stars aligning or what?



Unfortunately, the "kit" did not come with the "blueprint" that Rosenthall offers and when I tried to purchase it from the website (http://www.rosenthal-flugmodelle.com...720cm-plan.php), I find that they do not seem to want to sell to North America.

Does anyone know of another way to acquire the plans?

[AureleAlain]

Gudmund,

In fairness, Wes' Fries are pretty good so no apologies for your shortened flight. I might have some obechi that you can have if you need it.

Aurele

[Gudmund]

So I am thinking about the construction of the wing for this beast, and I am looking for a majic program that will tell me how much carbon fibre / fibre glass / end-grain balsa / obechi / etc. to use to build a light but strong wing.

I have been following the Eta Biter build thread carefully and Mike's building technique is interesting, but I am reluctant to use same cf rod material for the spars.

I do have a large - broken - wing that is available for autopsy that will give me insights into the thickness of materials that were used on a commercially produced cf/fg/foam/obechi wing that flew very well.

I also have the design advice that is provided by Joe Wurts and Oliver Wilson through the Charles River site on the subject of how to calculate material requirements for wing construction. I used these sources in the past to design a reasonably successful TD model (though as I remember, with stronger winches and higher launches the wings eventually folded).

Does anyone have any suggestions as to where I should look for an alternate, perhaps big-scale-sailplane specific, calculation program that I can play with?

[Len]

Hi Gudmund,

Congratulations of the project. It should be a real beauty when done. I don't have the experience or knowledge to accurately help you with those questions, but maybe you could send out a quick e-mail to one of the manufactures. Maybe Radim Horky at H-models or one of the guys at LET or KV models. I'm sure they would be happy to help get you going.

If I can help get you in touch, let me know.

LEN

[stihac]

Gudmund,

Looking forward folowing your build! It going to be a very cool project

Petr

[Rossco]

Gudmund everything you need to know spar calculation wise is here in this article I found some years ago

http://www.cb-roter-baron.de/framemodelle.html

Enjoy

[Rossco]

Gudmund everything you need to know spar calculation wise is here in this article I found some years ago on the ash 25.

http://www.cb-roter-baron.de/framemodelle.html

Enjoy

[yyz]

Very nice. Are you going to build it with a flapped wing?

Mike

[Gudmund]

Gudmund everything you need to know spar calculation wise is here in this article I found some years ago

Thanks Rossco. I will look into it.

[Gudmund]

Very nice. Are you going to build it with a flapped wing?

Mike

Mike - I hadn't even considered any other way. Until now!!

Update - OK, I have thought about it - a little - and I think I will go with the flaps.

I like being able to lower the flaps during the landing phase to establish a quicker than normal descent rate, that I augment with the spoilers. I also have a bunch of channels on my radio that I like to use!!