Although Intermezzo 100 looks very similar to my UAV Flying Wing it's a complete redesign. Smaller, more efficient, more agile and faster with a fuselage big enough so that it can carry some of my gadgets. All the electronics including the battery are velcroed to the 50x40x340 mm platform.

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Specifications
- Kline-Fogleman KFm Airfoil
- Wing span 100 cm (39.37 in)
- Wing area 17 dm˛ (1.83 sq.ft.)
- Aspect ratio 5.9
- Weight 500 g (15.17 oz.) (including 1350 mAh battery)
- Wing load 29.4 g/dm˛ (9.34 oz./sq. ft.)

Materials
- 4 mm Depron
- 4x4 mm spruce spars
- 2 mm plywood for the fuselage frame
- 50/25 mm reinforced tape
- double sided tape for the servos
- foam contact adhesive (UHU Por)
- epoxy glue (Araldite Rapid)
- 2 1 mm steal push rods
- 2 control horns
- 400 mm Velcro to mount the electronics
- 8 neodymium magnets for the canopy lock

Electronics
- TURNIGY 28-36 1200 Kv brushless motor
- Graupner CAM 8x4.5 folding propeller
- TURNIGY Plush 25A ESC
- Rhino 3S1P 30C 1350mAh LiPo
- 2 x HXT900 1.6kg/cm servo

Design tools I used
- ProgeCAD 2009 Smart (free AutoCAD clone)
- WinLaengs4 (CG calculation)
- Drive Calculator (power system calculation)

Building Intermezzo
Most of the parts are assembled to layers and the layers are stacked to build the fuselage and the wing. This drawing in combination with this one shows you which layer contains which Depron parts. The first letter of a part's designation tells you where it belongs to (fuselage, wing, canopy, nose) followed by the part number which identifies its layer (from top layer 1 to bottom layer 5).
The layers 2 to 5 are reinforced with spars and this drawing shows you how they are integrated.
These pictures should help you to understand how the layers are put together whereas these pictures show different angles of the assembled plane.

Use a flat surface to assemble the layers. A contact adhesive like UHU Por simplifies the build.
You best start with layer 5 by gluing the two spars and the Depron parts together. Then reinforce the joints between the fuselage and the wing parts (F5 and W5) by using reinforced tape (like shown here).
Now build the layers 4 and 3 in the same way on top of layer 5 and don't forget to reinforce the joints between the fuselage and the wing parts with tape. For layer 4 bevel the leading edge of the ailerons and tape them to the layer like shown here before you glue it on top of layer 5.
Install the Servos and the servo lead extensions like shown here.
Bevel the leading edges of layer 5 and layer 2 like shown in this drawing (method 1). Tape those two layers together like shown here and then bend layer 2 on top of layer 3 and glue it in place (the result should look like this). After that glue the spars of layer 2 in place.
Assemble the winglets like shown here and glue them on to the wing.
Now assemble the plywood fuselage frame (partially shown here) and layer 1 (part F11) and then glue it on top of layer 2.
The upper nose cone is built with parts N11 (outer) and N12 (inner) whereas the lower nose cone is built with parts N13.
Glue the side walls (C12) to the canopy top (C11) and reinforce the joints with C13. The finished canopy should look like this.
It is recommended to protect the fuselage bottom with tape like shown here.

Settings
- neutral (level flight): elevator 3mm up
- elevator up max.: 16 mm
- aileron up max.: 18 mm

Modifications
- revision B: added rulers and two missing parts to the CAD files


The "Making Of" video

Intermezzo 100 - Depron Flying Wing (2 min 50 sec)

Very professional looking as usual! Nice work Jaron, hope it treats you as well as your past wing.

Curt

Excellent work Jaron - you are fortunate to have access to a laser cutter.
But as you said, it can all be done with a sharp knife/scalpel.

I found (and ordered) an interesting folding pusher prop - made for the Easystar but might be useful anyway
http://ahm-rc.de/index.php?cPath=6_13

Nigel.

Thanks guys! It's always nice to have your work commented.

Nigel, I've done some experimenting with the cheap Hobbyking folding props and found them to be not as efficient as the fixed ones. But I'll give it another try and buy a better one from my local hobby shop. I believe he's got the Graupners.

It was such a nice day today and so I decided to do some flying.

Wow really nice work jaron! I really like the use of the laser cutter in construction. Great video too.

I can't wait to see it in action.

Thanks zik, I hope winter is coming to an end soon!

As it was cold and windy here lately I only flew Intermezzo 100 four times and it's difficult to make a final conclusion about it's performance - especially without any data.
Overall I'm quite impressed. Despite its higher wing load it seems to have a lower rate of descent than UAV Flying Wing. It also glides better but has a higher tendency to tip stall than my other designs.
Because I changed most of the design parameters, compared to UAV Flying Wing, it's hard to say what the reasons are that make it fly different/better. It could be the wing geometry or the KFm airfoil with more but lower steps.
I'll try to cure the tip stall tendency and in a next revision of the design I will probably have a deeper wing chord or a more aerodynamic fuselage - for all-round or speed.

I made two test flights today and logged some data. It's not representative but gives an idea of Intermezzo's flight performance.
For the logging I used an ArduPilot (Arduino), an EM-406 GPS receiver, an OpenLog data logger that writes on a microSD card and an Eagle Tree data logger.

Setup
- AUW: 536 g (18.9 oz.)
- Motor: TURNIGY 28-30B 1050Kv
- Propeller: 9x5 folding
- Battery: 1350 mAh 3S1P

Powered flight
- Maximum speed at level flight: 55 km/h (34 mph)
- Maximum climb rate: 6 m/s (20 fps)
- Motor Amps average: 9 A
- Motor Watts average: 99 W

Gliding
- Maximum speed in a dive: 98 km/h (61 mph)
- Average speed during glide test: 42 km/h (26 mph)
- Average rate of descent while gliding: 0.53 m/s (1.7 fps)
- Glide ratio: 1:6.26

I flew jaron's Intermezzo 100 today. It's a great plane!

This plane has very precise control - it really does fly like it's on rails. I found it very confidence inspiring and stable in the air while still being maneuverable and great fun to fly. Unlike many flying wing designs it has very little tendency to tip stall. It performs well through a wide variety of airspeeds and has good glide capability for a plane of its size.

I was impressed enough that I'm thinking of making a similar plane for myself. The only tricky part of flying it is the launch - as with any powered flying wing it requires a little skill. I'd recommend this plane to any intermediate or better flyer. Its precise flight characteristics are a joy and with the power system jaron's using it can really move too!

Originally Posted by zik

I flew jaron's Intermezzo 100 today. It's a great plane!

This plane has very precise control - it really does fly like it's on rails. I found it very confidence inspiring and stable in the air while still being maneuverable and great fun to fly. Unlike many flying wing designs it has very little tendency to tip stall. It performs well through a wide variety of airspeeds and has good glide capability for a plane of its size.

I was impressed enough that I'm thinking of making a similar plane for myself. The only tricky part of flying it is the launch - as with any powered flying wing it requires a little skill. I'd recommend this plane to any intermediate or better flyer. Its precise flight characteristics are a joy and with the power system jaron's using it can really move too!

Zik... this is wonderful news. I am so happy to hear that Jaron's Intermezzo flies so beautifully. Your report has made me a very happy man indeed. I was very curious about how his KFm7 airfoil would perform. Now I know thanks to your posting. It really put a smile on my face.

Dick Kline

Intermezzo's twin brother is born - I had some parts left over from the laser cutting session and thought they'd look better assembled.
It needs a power system and a receiver and maybe I'll just store it in case Intermezzo #1 crashes.

Do you see longer flight times with this one over the original design?

mecevans, Intermezzo 100 has a motor with 70 W more power and I'm pushing it harder than UAV Flying Wing. The flight times are about the same with 12 minutes for the 1350 mAh battery (no camera or additional electronics).
It's a small plane with a limited payload but sometimes I'm flying it with a 2200 mAh battery. I haven't done much flying lately because of the bad weather but as soon as it clears up I'll do some endurance testing.

Suggestion: Include something in the CAD file to scale the drawing from. For some reason when I downloaded it, it was not to scale, and since i have no known dimension, it is hard to guess.

Question: What is the payload capacity if you had to guess? My problem is my FPV gear is pretty heavy, and worse, I only have 2200mah 3s batteries, so I am getting up there in payload. Wondering if i need to scale up...

Derek, what's the weight of your FPV gear? I can't tell you what exactly the payload capacity is but I have flown the plane with a 2200 mAh battery and about 50 grams of additional payload.
The higher the wing loading, the faster a plane flies and the more critical are its stall characteristics. Therefore I would choose a plane with a lager wing span and maybe made from EPP which is more durable than Depron.

Thanks for your suggestion about the scale in the CAD file. I added an updated ZIP file in post #1 (revision B).

Hey man, great design! I was searching around for some stuff and found your last blog with the seaplane wing and was really impressed. Glad to see you're still at it!