Foam Board Wing

Fly_electric

Well-known member
Too long a story to get into, but while work remains busy, I have been trying since March (the CrazE) to get in some real world flying. Need a more expendable model, as flying has to be from within the perimeter chain link fence at work in the summer. Finally zeroed in on a foam board wing and a cheaper motor, in the event the fence is hit. Still learning the details on building a wing like this, so while others may build it in an afternoon, free time and learning has resulted in a build time embarrassingly longer...

Anyway, the flying wing calculator site says this thing should fly, and the CG is set to the most forward %MAC. To help prepare, I've also been using a RF version. The physics have been set as close as possible to the RW model, so when maiden flight time comes, am hopeful the results will be close to what I've been seeing in RF. The RW plane is pretty much done, and am now setting up the control throws, and soon will set the throttle limits to keep the Park 480 happy on 4 cells.

The RF version is still a bit rough, but it is coming along as well, so figured it was time to share some progress shots. The RF version will get posted, but as its main purpose is to be a guide to being as close as possible to the flight characteristics of the RW plane, the maiden and some more test flights will happen first-- hopefully there will be more than one flight... :).
Note: the three polygons represent the CG range as shown by the on line calculator: green is the most stable and red= the "danger zone". I find such markers useful in setting up the physics, as I now tend to model planes from plans and start with the recommended CG location. The polygons will be removed before posting as shown in the Max renders.

Note: I use to see the picture displayed in posts, now just the file name is shown. Has there been a web site change??
 

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nice to see you have those projects progressing none the less FE , i'll be waiting to hear your comparisons between the RW and RF , nice work clean looking build and gear setup
 
Update:
The RW FBW has been successfully maidened this past weekend.
Amazingly (to me anyway) for a completely scratch built design it flies very well with no adjustments needed. With those 4 completed flights as a bench mark, I went back to the RF version for a comparison. Was not quite the same, being sensitive in pitch at full throttle and not penetrating too well in landing.
Thank you to CloudyIFR for finding the error.
On a conventional plane, the aileron area is included in the calculation for W.L. For a flying wing that is not the case. RF (or at least ver 7.5) does not make that distinction. Adjusting the physics to reflect the wing loading of the real world FBW, and the RF version is now very accurate.

RF version:
Added some more details:

Motor wires
Duct tape (used to keep the motor wires in place at 50-->70 mph)
Mounting HW
Mapping completed on all the new parts

Also, while the CG markers are useful in working with the physics, they don't look too great. So, to make them available or hidden as needed, they are now an "Engine To Show" object.

Unless I've missed something, it should be all CS work now to reach the finish line..
 

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If you're gonna use an Eflite battery we won't get that many out of it before it puffs and becomes unflyable .. hehehehe. Maybe put in a Pulse or Gensace.
 
Nice renders and a cool project it will be fun to fly when your finished. I can't wait I want it now :)
 
Wow, really nice. Makes me want to build the Toro 900 that I used to own.

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If you're gonna use an Eflite battery we won't get that many out of it before it puffs and becomes unflyable .. hehehehe. Maybe put in a Pulse or Gensace.

Guess everyone's experience differs.
Since getting into RW flying (guess guiding the 350QX for photography is sort of like flying), have used only EFlite packs. The 350QX was designed with an EFlite 3S pack, and all (oldest will be 4 years old next Spring) work well. DID have a new pack puff last year, but that was my fault-- did not have a charger to handle a 4S, and it sat on the shelf for about 10 months with whatever charge (and however long ago) it left the factory with. Don't fly much with 3S packs as they are too inefficient for my taste, but am considering using two of those older packs on a new FBW (maybe 1.5X to 2X larger) and fly as 6S.

Another difference perhaps is I always follow the Balance Charge/Fly/Storage Charge sequence and record the capacities (helps me determine how well I am following the "use 80% of charge" guideline). As I only get one flight (or two with two packs) at a break time every few weeks as work and weather permit, I never BC/Fly/BC/Fly again/SC. Throttle upper end is set for little less than static max of motor current with the prop and pack I want to use and make some initial run time checks to see what % usage there is at full throttle. Then for flight, set the timer for an additional minute due to lower prop loads. In this case, static was for 3 minutes and started first flights with timer for 4 minutes. Am up to 5 minutes as of the last 2 flights, and with usage about upper 60s to 70%, will probably increase the timer to 6 minutes.

So, have no problems with EFlite packs. Nice thing about the hobby, is there are several manufacturers to choose from.

Other (moving even slower..) project is a 3d printed custom "H" frame quad copter. Bigger than the 350QX to handle larger batteries, camera, FPV, etc and 13" diameter props on the AXIs. Expect to use a 6S pack there. May use an unused pack from work as it is available and will literally otherwise will just sit here and eventually puff.
 

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As time has allowed, a few more details added:
Motor label
Motor cooling "holes"
Mobius

The RW FBW has about 8 flights on it now. Having seen a similar arrangement done on a CrazE, I'd like to add a rearward facing Mobius (rearward so as not to "sand blast" the unprotected lens). Have not as yet figured out the attachment method I'd like, but added the Mobius to the same approximate location on the RF version.
Have also added the Mobius as a camera to the physics.
 

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Getting closer to posting the Foam Board Wing.

Few more CS details are in such as all the gift card sections and maybe a bit more to do on the physics adjustments.
One observation (true in RF6 and RF7): the hand launch is not very realistic.
The real plane basically leaps out of my hand, but in "hand launch" RF always drips initially until it picks up speed-- rest of the flight characteristics match. The "discus launch" is closer to the real plane response.

Some newer renders..
 

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And some screen shots.
 

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