Build log - 150% "advanced" soarer

stay-fun

Helicopter addict
Hi guys,

I have a project I want to work on. It is going to be a glider, based on the FT Simple Soarer designs. However, I'm going to remove the dihedral and polyhedral, and add ailerons and flaps. Hence: "advanced" soarer. Also, it's going to be bigger, so it can handle more payload (FPV gear, laaaaarge battery, and pixhawk autopilot).

The reason to take the 150% value is that the wing will consist of 3 foam sheet lengths. That results in a wing span of 2.2 meters, or 7.3 foot. The plan is to have a middle section, which may be glued to the fuselage, and 2 removable outer sections. I plan to use Josh B's method of wing joining as he and David show in the monster plane build video.

Here is a picture of printed plans with my own dimensions (in centimeters):

IMG_20140627_213912 (1280x960).jpg

Annnd while designing this on paper, I run into the first thing I'm wondering. I intend to use the entire trailing edge of the wing for control surface, but how much of that should I use for aileron, and how much for flap? I want to be able to use the 'crow' mode (flaps down, ailerons up) for braking when I come in for a landing. The easiest would be 70% aileron, and 30% flap, because that's where the foam board joins... But is that useful or should I shoot for something different? It's possible to make the ailerons smaller and the flaps bigger, which will result in a larger middle wing section.

I'm going to use this thread as a build log, and questions about what I want to do will come along as I build, and I'll keep you guys updated, with pictures and a maiden video (at some point... :p). I'll also keep this first post updated.

Update 1
Sorry for the wait guys, kinda busy and stuff. The wing is nearly completed, and consists of 3 pieces which will be detachable for transport. I've made the servos removable, so in case of a crash it's possible to replace them. Flaps and ailerons are all 42 cm long, there are undercambered wing tips. The spar is made of basswood. I reinforced the spar area with fiberglass also.

IMG_20140629_165555 (1280x349).jpg

IMG_20140707_190954 (1280x960).jpg

IMG_20140707_191002 (1280x960).jpg

IMG_20140713_141727 (1280x960).jpg

As you can see here, I had to move the servos closer to the spar, otherwise I couldn't make the flat bottom fit...

IMG_20140720_170722 (1280x960).jpg

IMG_20140720_213532 (1280x960).jpg

IMG_20140720_214029 (1280x960).jpg

The spars are interlaced, and there is a screw holding the outer part of the wing on. Initially I also wanted to screw the 2 spars of the middle section to the outer part, but I think it's way overkill (and a lot of work).
 
Last edited:

stay-fun

Helicopter addict
Thanks man!

I started to draw the plans onto foam board, using 1 foam length for ailerons, and the middle foam board for the flaps. Turns out, the ailerons are going to be more than twice the size of the flaps! Is that useful...? Or do you guys think it's a good idea to shorten the ailerons and make the flaps longer? That's possible but will be difficult with alignment, since the flaps will then contain a seam where the two foam boards are joined.

The other option is to go for a 200% soarer, but... That's rediculously huge...

What do you guys think?

IMG_20140628_172116 (1280x960).jpg
 

stay-fun

Helicopter addict
I have decided to split the wing into 4 pieces of foam. The inner 2 sections (with the flaps) will be 48 cm long, the outer 2 sections 61 cm (with the ailerons). Flaps and ailerons will both be 42 cm (42... the answer to everything :) ).

I'm keeping undercambered wing tips (without control surface) for gentle stall characteristics.

The inner 2 sections will be glued, the outer 2 sections will be removable (so it will be a 3-piece wing in the end). I'm going to use a basswood spar, and I'm going to reinforce the spar area with fibreglass. This will allow for screws to bolt in, for (dis)assembly.

IMG_20140628_223632 (1280x960).jpg
 

stay-fun

Helicopter addict
Alright, yesterday I've put the fiberglass on the spar area, and here is a picture of the wing:

IMG_20140629_165555 (1280x349).jpg

The two middle sections will be permanently joined, the 2 outer sections will be removable. The longest basswood spars are 123 cm long, the cutout for the middle spar in the middle wing part is 76 cm, the spars in the outer parts are 46 cm. They extend 10 cm into the middle wing. Tonight I'll epoxy them in (my epoxy is slow cure, West System 105+206). I'm adding a little 403 microfiber to make it more viscous. The reason for expoxy vs hot glue is the slow cure, there is no way of doing this that fast...
 

stay-fun

Helicopter addict
Hi guys, I updated the first post! It's been a while, I was busy with other builds and (non-RC related) social stuff. But I've gotten back! The wing is almost done. Then for the fuselage...
 

Flat4

Senior Member
Alright, yesterday I've put the fiberglass on the spar area, and here is a picture of the wing:

View attachment 26088

The two middle sections will be permanently joined, the 2 outer sections will be removable. The longest basswood spars are 123 cm long, the cutout for the middle spar in the middle wing part is 76 cm, the spars in the outer parts are 46 cm. They extend 10 cm into the middle wing. Tonight I'll epoxy them in (my epoxy is slow cure, West System 105+206). I'm adding a little 403 microfiber to make it more viscous. The reason for expoxy vs hot glue is the slow cure, there is no way of doing this that fast...

Come on, you got with the hot glue. I folded over a 100" wing with hot glue, just had to do one half at a time. Seriously though, I wish I would have used epoxy, I got it done but that was crazy stressful. Wing looks good so far, is that spar strong enough to prevent flex from the trailing edge of the wing? I had to ad a tongue depressor on the trailing edge of one wing half for the other to slot into to stop any slop back there. Then again I suppose if you mounted the wing with rubber bands they should do that for you.

Nice looking wing so far, looking forward to seeing more.
 

stay-fun

Helicopter addict
Thanks man! Yeah I dunno about hot gluing that, according to the monster build log, hot glue cools pretty fast on wood. And I'm not convinced about adhesion properties of hot glue on fiberglass, although I didn't test it. Anyway the epoxy worked just fine :).

Hm I didn't consider wing flex to the trailing edge... I guess I can always glass the wing later, but I hope I don't have to...
 

stay-fun

Helicopter addict
Still working on it... I've been quite busy with my other big hobby (dancing) which took quite some time. I intend to finish it, but these other things have been taking up my time so it's going pretty slow at this point. The wing is completed (geez it's large!), it has removable servo hatches and (I think) reliable wing join method.