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Old Mar 24, 2015, 12:07 PM
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I've been so busy lately I haven't had time to post back. The other day I fired up the bixel and ran it around. I didn't get in the air but I learned a lot.

Differential thrust worked out very well. At 40% mix it was very responsive, too much for this thing, but would be great on a hovercraft. I turned it down to 20% and it was more reasonable.

I did a bunch of fast taxi tests and by the time I worked out the needed thrustline it was just too much of an angle. I played with the balance and chopped it up in stages, gradually changing the outer panels and edge bevels. I beat it to packing peanut during tests but now I've got a better feel for it.

I'll do another one soon with what I've learned from this one.

Thanks again for all the tips, I appreciate it!

I'll post here soon with more ekranos!
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Old Mar 24, 2015, 01:44 PM
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the farther from cg the prop, the less angle needed to reduce power/pitch couple.

sounds like it is not 'Bixeling'. the Bixel should want to lift off at a high taxi speed because its AC moves fwd ige while most other flying machines do the opposite.
my first model which was a rectangular very low aspect ratio(VLAR) which refused to lift off until I moved the cg back, and then it was impossible to control it.
did any of ur mods have the same dimensions of the Bixel?
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Old Mar 24, 2015, 01:48 PM
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Quote:
Originally Posted by nbrophy View Post
I came across this tandem wig model while searching for other wig models on the web.

Disclaimer: I have no affiliation with the seller, just thought Id share with others.

https://spacecoast.craigslist.org/tag/4867359677.html


very pretty WIG. must be for very low water clearance. the planform and engine/cabin placement suggests a CG too far aft for involuntary OGE flight.
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Old Apr 10, 2015, 11:08 AM
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I was inspired when I recently built a polaris and it enters ground effect right before takeoff.
So i want to build a A-90 Orlyonok any tips?
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Old Apr 10, 2015, 03:25 PM
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wow! ive been asking guys from the polaris forum to test it in GE! please give us more details!! did it lift off and maintain height hands off? or did u have to level it off and it maintained that height IGE?
this is exciting!
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Old Apr 10, 2015, 10:32 PM
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captarmour, i flew the polaris in quite tall grass and if i throttle up(like takeoff) it feels like it enters GE flight (if i don't pull back on the stick).. I can't see the space underneath but i can feel the GE affecting the "ground" handling of the plane.. or maybe it's just the grass that's pushing the plane up who knows? i'll do a bit more testing this sunday and report back..
My polaris has an AUW of 17oz so that might also affect the performance.
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Old Apr 12, 2015, 06:18 AM
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thanks a mil.
what we r looking for is evidence that the aerodynamic center moves forward instead of back IGE. in other words when it gets to lift off speed it should start pitching up, or rotate but as it climbs, it should it start to get nose heavy as the AC moves back. a slightly nose heavy balance and trimmed for a gentle descent when OGE may assist in this.
to confirm check that OGE it descends 'hands off'.
looking forward to ur results.
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Old Apr 12, 2015, 10:04 AM
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I just tested it this morning, (they already cut the grass) i definitely think it got some ground effect.
I noticed no pitch up upon entering "GE" but if pull back on the stick no additional throttle is needed to lift out of GE... so it might not be GE it's entering but just stable flight near the ground and not exactly GE as described a few pages back on this thread..
I have some on board footage (nose view only) and possibly some footage from the ground (will update once i get a hold of it)
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Old Apr 12, 2015, 09:26 PM
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it climbing out of ge with up elevator is fine. a normal wing is nose heavy ige which means it doesnt want to lift off without up elevator, but when it lifts off it starts to become tail heavy and wants to climb away. what u looking for is for it to level off hands off ige. if u pull it up out of ge and let it go it should start to descend. if u level it off ige and let it go it should maintain height.
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Old Apr 12, 2015, 09:50 PM
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i'll try to post the on-board video later tonight as i don't have the cam right now.
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Old Apr 23, 2015, 05:02 PM
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Ekranojet!

More details later.
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Old Apr 27, 2015, 03:03 AM
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Okay all, i finally got some time to post some info on the above bixel-jet.

First of all, it seems to be working. IGE it's like an air hockey puck, picks up at a fast taxi speed. What surprised me was when i flew it OGE.

And i mean FLEW! Hehe!

So i got it cruising in ground effect and gave it some up elevator to see what would happen. It breaks out of GE and pitches up into a solid 45*climbout while still accelerating. I never really got to open it up, but i flew it up to about 50' altitude, steered, hovered in wind, and brought it back down to a smooth landing several times.

It's stable and can be flown either IGE or OGE as a funny looking parkjet. I think i'm going to do some elevons on it and a CC3D stabilization system with some sort of radar/sonar altimeter and forward looking obstacle avoidance system if i can get it to work. It currently has a single 64m 8 blade EDF on a 3s 2200, but i'd like to try 4-6 cells and a pair, or two pair of some more serious EDFs.

It seems like it could really handle speed if i built it for that, so i'm thinking of a fiberglass over foam hull and balanced control surfaces to handle high speed.

I'm figuring that with FPV gear, a good tracking antenna, and a dry lakebed flooded with monsoon rain a lot of fun could be had with an actively stabilized jet bixel at full tilt, twin or quad edf jet speeds. I've also been wanting to try a pulsejet project of some sort, maybe a PJ Bixel would be an interesting project.
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Old Apr 27, 2015, 08:39 PM
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love it, the bixel is a great planform. the outer wings r flying in an upwash so the lift vector is tilted a bit forward, that may make it fast!
is it balanced for a gentle descent oge but maintains height ige?

looking forward to some video.
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