RETjet Nutball-ish Slender Delta(great plane, beta stages!)

Vimana89

Legendary member
On second thought, I'll deal with that one separately and keep this thread focused. 550 batteries should arrive Monday, and I plan to have the next RETjet with canards ready by then.
 

Vimana89

Legendary member
Had an incident with the AET yesterday.Launched into moderate winds then some gusts picked up and took it. I should have just brought it down when it started drifting, but I fought and tried to reel her in. Went across the desert lot and I believe the highway. No clue where the crash actually ended up, maybe it made it all the way to the streets/houses past the highway. More worried about it causing trouble for somebody than the inconvenience of $60 worth of parts. Anyone else had that happen, just lose a whole plane and not find where it ends up?
 

Vimana89

Legendary member
Anyway, RETjet next build coming along good. I modified the fuselage to be even more identical to the Kolibri Flyer, but with very slight differences geared to my personal construction and assembly style as well as the size of my available firewalls. My canards came out similar but not exact in shape, a bit lower profile. They reflect the lines of my airframe more but should function about the same.
 

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Vimana89

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Ridiculously windy the past few days here. Once I get the next one finished and am able to test I'll update. Besides that, expect video of the first prototype most likely tomorrow. YouTube won't properly finish uploading my videos as is, and no converter will do that big a file for free, so I will be buying an unlimited membership to a reliable service tomorrow.
 

Vimana89

Legendary member
2nd prototype flew well by sluggish, because I used and blew out a motor that was only meant to go ccw on clockwise pusher. Another lesson learned. Plane is back from a good but not optimal flight in one pretty piece, doing a motor transplant with my FT radial of the same size and power...but that motor has a problem I gotta address, the shaft is too long to fit a prop snug without using two washers.maybe a defect? Been putting off asking about it/trouble shooting it.
 

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Vimana89

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Rocket surgery a success. She flew again, but winds getting nasty so my whole short flight was fighting the wind rather than testing capabilities. She's back in one piece again now with a couple minor creases, tonight and/or tomorrow I'll get my video stuff squared away and test more. I have some footage to review of mk2, not very impressive due to the motor mismatch on flight one and wind on flight two, but she's there flying.
 

Vimana89

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mk2 flying good and still in one piece after several flights! There's some control slop and stuff still, but the plane flies reliably and is capable of nice loops at full throttle. It turns on a dime, as sharply as any elevon plane or better,and the dihedrals help with self leveling, and make tip stall pretty much impossible. These batteries are less than ideal for their weight as 550 mah, but they were cheap. Tattu 650s of the same c rating weigh less and are slimmer. This build can do some high alpha but not as much as some other builds I experimented with, and not like the Kolibri flyer. Maybe it's just me?
 

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Vimana89

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Another great test session. Two batteries again(these high discharge 550s go pretty fast), no crashes. The more I fly the plane, the more I realize what I've effectively done is create a trainer for slender deltas and other highly swept, more demanding to fly planes. This has the a very similar feel in terms of handling to a low aspect AET or elevon plane, but with the self-righting effect of dihedrals and RET control scheme. This thing is still a slender wing plane with sensitive bank/roll and decent high alpha, but it is self-leveling, impossible to tip stall, and has a very smooth and stable pitch which is made even better by the canards. If you want to build a gorgeous Concord or HP-115 but are not used to these types of flight characteristics, a good option is to try the RETjet first. It's less demanding in build time and flying. It doesn't have quite the flight envelope of a Kolibri Flyer, but is a bit more beginner friendly. Also a good choice for transitioning from trainer planes to anything along the lines of deltas or jets. I'd say from my personal experience that it is a good bit easier to fly even than a straight nutball.
 

Vimana89

Legendary member
Still haven't got a chance to sort out the video situation, but I am sitting on some decent footage of the first prototype and the current build as well. That will be coming soon along with some modest sketches and build instructions/tips. I'm no good at making tiled plans and exact specs are still somewhat in flux between prototypes, so I will give some sketches of the basic components and finished plane, and approximate dimensions. I'm leaving room for experimentation and development and personal preference on things like exact dihedral and thrust angles, size and style of vertical stabilizer and rudder, belly fuselage options(full A fold box or two-sheet thick spine with cables taped along).
 

Vimana89

Legendary member
footage is finally available and up on reserved footage post, but I'll put the first vid here too! This is the mk2 with canards after many successful flights and a couple small bumps. Mk1 footage will be available shortly and available on the footage post along with this veideo and future video clips of this plane.
 

Vimana89

Legendary member
Video footage of prototype one and two are both available in the footage section on page on of the thread. Any input, comments, suggestions, are all welcome. Right now I just have raw footage with no commentary, editing, music, etc. but its enough to show my planes flying. There's still things that need polishing with the designs, mostly build neatness, as the design specs are pretty much where I want everything. you can literally hear the control slop in #2 when I yank the elevator hard, but again, these are somewhat rushed prototypes.

I'll be adding a build guide as best I can. It will not include exact printable plans unless somebody else decides to help with those, but this plane is easy to build and flexible like a Nutball, one could literally just look at a picture and build it by eye to whatever exact scale they want.