Scratch Designed/Built Sailplane Fuselage
 

This is a continuation of a couple of build threads I've been working on...
<ul>[*]Scratch Designed/Built Sailplane[*]Sailplane Wing Design Round II[/list]My original design flew beautifully but suffered from a design flaw in the wing (consequently it folded in half mid-flight). Since that fun learning experience I've redesigned &amp; rebuilt a better wing. In fact the new wing turned out so nice that I'm reluctant to fly her with the original fuselage. So I'm going to redesign/build that also. This thread will document that process. Subscribe if you're interested.

RE: Scratch Designed/Built Sailplane Fuselage
 

A new look
While I liked the profile of my old pod-n-boom design, seeing as I'm rebuilding this from scratch I have the opportunity to change the design if I wish. Here's a few "out there" ideas for the new pod. I'd love to hear your thoughts on which if any you like...

http://www.scipie.com/rc/vee-gull/3D...ng_010_700.jpg

Let me know which you like &amp; why.

RE: Scratch Designed/Built Sailplane Fuselage
 

I'll be watching. Really enjoyed the first two, especially the rebuild of the wing.

Personally, I liked the original fuselage profile the best. It looked the sleekest and the neatest. But, since you asked, out of the new ones, I like B because it is the slimest, and sleeker of the bunch, and I like E because it looks like a bird.

RE: Scratch Designed/Built Sailplane Fuselage
 

A looks like the rear of the pod is a little abrupt to me.

B or F, leaning to F because it looks like a motor with 3° or 4° of down-thrust would blend in well.

C,D,G, H, and I might disturb the air over the center-section causing more drag. The C might not need down-thrust due to the high thrust line.

I don't get E.

RE: Scratch Designed/Built Sailplane Fuselage
 

Making it really tough to pick just one. I would have to go with F. The lines blend in better as soarrich put it.
A and B look like something you find on some of the scale ships today.
I reminds me of some of the designs back in the 50's and 60's. All good.
Something of an elongated tear drop would be cool.

RE: Scratch Designed/Built Sailplane Fuselage
 

Of the lot F and B are the sleekest to my eyes. And truth be noted there's precious little difference between them. It also sets the fuselage at an angle that will be decently close to the airflow coming up to the leading edge of the wing. Second in looks and streamlining, but not by much, is A.

The rest are either angled to promote too much "belly onto the wind" or simply look odd for no purpose. For example D is simply an act of desparation calling out for an intervention.... :D Funny yeah, but it's ugly on so many levels at the same time. Same with the "bird's head" on E. And the lump on the belly of I looks like a tumor.....

RE: Scratch Designed/Built Sailplane Fuselage
 

I prefer I as it increases the wing tip clearance on landing and has the thrust line on the wing centre, it also give a skid type underside for landing on.

Mike

RE: Scratch Designed/Built Sailplane Fuselage
 

Great feedback, thank you all.

I've pooled the opinions from this &amp; my mirror threads on other forums &amp; as expected, the more modern sailplane profiles (A, B, F) were the most popular. I could certainly go with one of those &amp; end up with a very nice sailplane. However after thinking about it some, I've realized I'm not necessarily looking for the most efficient, most sleek design. I'm now leaning towards doing something a little out of the ordinary. Something that'll stand out in the crowd. The gull wing achieves that goal to a point but I'd like a "quasi-vintage" fuselage to go with it.

So here's another batch of doodles...

http://www.scipie.com/rc/vee-gull/3D...ng_011_700.jpg

A2
Modern sailplane profile, while sleek, lacks uniqueness.

B2, C2
Has a subtle avian feel (looks a little like a bird's head). I think these tie in wonderfully with the gull wing. Flying a giant bird might be fun.

D2, E2
An under-slung pod design. Inspired from some vintage sailplane designs I've seen. Again these work with the gull wing &amp; would be a little different.

Once again I welcome comments &amp; thoughts.

RE: Scratch Designed/Built Sailplane Fuselage
 

E2 with the boom moved down to the back of the pod would be kind of Supra-ish.

RE: Scratch Designed/Built Sailplane Fuselage
 

A2 with the E2 pylon. Sort of what soarrich had in mind. Think you are on the right track for something unique.

RE: Scratch Designed/Built Sailplane Fuselage
 

That's an interesting idea soarrich. Here's how that might look...

http://www.scipie.com/rc/vee-gull/3D...ng_013_700.jpg

Under-slung pod
I'm leaning more towards an under-slung pod design, pretty sure that's where this is sailplane is headed. Its fun, different &amp; I can't see any major reasons why it shouldn't workout. So here's a new set of doodles...

http://www.scipie.com/rc/vee-gull/3D...g_012a_700.jpg
http://www.scipie.com/rc/vee-gull/3D...g_012b_700.jpg

RE: Scratch Designed/Built Sailplane Fuselage
 

Nodd,<div>L3 would make my day! Although you'd need much more tail fin for it to fly nice.</div>

RE: Scratch Designed/Built Sailplane Fuselage
 

Nodd, your creativity is outstanding. Like the under slung pod design. Partial to E3 also.
Would be more dependent on keeping a smaller frontal area so as not to induce any more drag then needed.
Then again, any of them would draw attention at the field.

RE: Scratch Designed/Built Sailplane Fuselage
 

I may have to make a chicken plane some day but not this day *grin*

Enough doodling
I could go on for weeks playing around with exotic pod shapes but I'd like to move on. Taking into account everyone's input (thank you) I've settled on this design that's a mixture of E3 &amp; F3...

http://www.scipie.com/rc/vee-gull/3D...ng_015_700.jpg

Artistic babble
While I like some of my more excentric designs, I think this one with its modern canopy merged with a retro pod works well. It has a few curves to keep things interesting without coming across as over-the-top.

Well I'm off to the LHS to pick up some wood. Time to start the build.

RE: Scratch Designed/Built Sailplane Fuselage
 

Now that is unique, a LHS with wood. Mine says "I could order it for you", I guess he thinks I don't have internet.:(

RE: Scratch Designed/Built Sailplane Fuselage
 

Yeah I know what you mean... "Balsawood? Do we look like a lumber yard? We do have over priced lumps of foam shaped kinda like airplanes though".

Well I'm back from the hobby store &amp; bah (big surprise) they don't have the sizes I need. I'll have to hit the other store tomorrow, either that or order some online. Thankfully I do have internet *grin*

RE: Scratch Designed/Built Sailplane Fuselage
 

Fleshed out
I did a little more work in CAD, here's how the pod looks fleshed out in 3D...

http://www.scipie.com/rc/vee-gull/3D...ng_016_700.jpg

RE: Scratch Designed/Built Sailplane Fuselage
 

Bounce Bounce Bounce
A guy over at RC Groups pointed out that my pod fuselage may cause ground handling issues. Specifically he felt the design would be prone to skipping during landing. Once the pod contacts the ground the tail will hit next raising the nose alarmingly &amp; back up she goes, hop hop hop. So to fix the issue I'm thinking a small tail-skid should keep the AOAfrom getting out of hand during landing. It looks kinda cool too...

http://www.scipie.com/rc/vee-gull/3D...ng_017_700.jpg

RE: Scratch Designed/Built Sailplane Fuselage
 

Construction begins!
Enough design work, time to start building this thing. I printed a set of templates from my CAD software...

http://www.scipie.com/rc/vee-gull/20120911_0001.jpg

Used the templates to cutout the various parts then started putting things together...

http://www.scipie.com/rc/vee-gull/20120911_0003.jpg

She's starting to look like something...

http://www.scipie.com/rc/vee-gull/20120911_0010.jpg

Filled in the rear of the pod with scrap balsa...

http://www.scipie.com/rc/vee-gull/20120911_0014.jpg

A little pre-shaping of the hardwood nose blocks. Once installed I'll finish carving these until the motor fits...

http://www.scipie.com/rc/vee-gull/20120911_0016.jpg

I'm using 1/4" plywood for the pod support (the piece that connects the pod to the wing)...

http://www.scipie.com/rc/vee-gull/20120911_0020.jpg

Test fitting the support. I won't glue this in until the pod has been shaped &amp; sanded as it'll just get in the way...

http://www.scipie.com/rc/vee-gull/20120911_0024.jpg

That'll do for today. I'm headed to the NEAT Fair so will get back to this when I return next week. Cya there.

RE: Scratch Designed/Built Sailplane Fuselage
 

If you have the wheel behind the CG it wouldn't bounce, as long as the wheel touches first.

RE: Scratch Designed/Built Sailplane Fuselage
 

That is exactly the problem. If the wheel is behind the CG on this fuse shape it can't touch first.

RE: Scratch Designed/Built Sailplane Fuselage
 

There's no doubt the first part of my fuselage to touch the ground is way out near the nose. Here's how she looks compared with a random collection of other sailplane fuselages...

http://www.scipie.com/rc/vee-gull/3D...ng_018_700.jpg

It'll be interesting to see what happens when I land her.

RE: Scratch Designed/Built Sailplane Fuselage
 

Not a lot to show today, started sheeting the top &amp; bottom of the pod...

http://www.scipie.com/rc/vee-gull/20120920_0005.jpg

Will have more soon.

RE: Scratch Designed/Built Sailplane Fuselage
 

Your's is better looking than the others. Keep going.

RE: Scratch Designed/Built Sailplane Fuselage
 

A-15 looks nice too, especially at its time (50 years ago). Great craftsmanship! Can't wait to see some flight videos..