Hi Mark,
I made a Rack Test with your Params. The reaction on the Yaw command is good, but not the stability a the Endposition. Similar like the drunken Pilot of my first tests.
Here the Log: https://drive.google.com/open?id=1UH0uG93kefdsP0ABgzCIAlmM1S_lV99Y
And the Params: https://drive.google.com/open?id=1vxy_xliTGxk-bSAlioqG6sBmDbVDPLtm
The Params of Roll and Pitch are set to Zero. This Axis are fix and with the correct params it produces hard shaking which disturbe the Yaw Test.
The same test configuration as with my params in post 515.
I guess that confirms that the RealFlight physics isn’t very accurate for this situation.
It’s therefore best to use the parameter values which @losawing has demonstrated to work well for his quad tailsitters as a starting point for tuning.
The value for Q_TAILSIT_INPUT won’t matter until you pitch down significantly in VTOL modes; use 2 if you want the yaw stick to work the same as for multicopters, or 3 if you want it to control bodyframe yaw.
Hi Mark
I was able to load the BiWing into Realflight 8… all other models within realflight work fine, but the biwing is not connected to the TX … instant full throttle, flips backwards and crashes.
Thoughts
Tim
Right, it’s not intended for manual control. The TX inputs are read by the autopilot, and the autopilot sends commands to RealFlight to control motors and servos. This is accomplished via the flightaxis feature in the RF8 beta I linked to.
You can read about how SITL works here: https://ardupilot.org/dev/docs/sitl-simulator-software-in-the-loop.html
Obviously, you can’t fly a multicopter, or a plane like this without either a flight controller or some fancy mixing in the TX. While RealFlight does have its own simulated flight controller, we don’t use it because our intent is to test our own firmware.
Yes, my Values are close to those of @losawing (jetwing) may be the high speed too? 
I wonder, why the Pitch and Roll Params are not far of yours (SITL) but the Yaw P and I are much higher, only.
But the field test will give the answer how they will work. Later, because Winter with snow came the first time since one year.
HI kd0aij, HI lorbass
Question 1
I wanted to try out SITL, so I bought the recommended RealFlight 9.
Unfortunately, no matter what RFX I import from you(@kd0aij), Tridge or IAMPETE – there is always the following error message:
Could not find contents file in caipirinha2_EA. Import Failed.
Do you have some thoughts on how to get around this?
Question 2
After doing some research on creating custom designs, I was terrified how messy, undocumented and inaccessible creating custom designs is. Knife Edge offers some Toolkits for 10-year-old software, blender is perhaps an option but who truly knows? There are many answers widely scattered around the internet, some to old for being viable.
Wouldn’t it be great having a YouTube Video, which shows how to create a simple custom vehicle step by step plus the assignment of properties in the RF Airplane Editor?
You have gone through this hideous research already and it would be so helpful if you could share your knowledge with us, so that others find a quick way into creating custom designs!!!
Question 3 & 4
Are flaps a necessity for a Quad + or could enough yaw authority from differential thrust be obtained?
I just read about pointing opposite Propeller slightly in- or outwards what results in increased yaw-authority.
Does a FlighControler configured with a frameclass for a Quad + handle this constructive finesse?
Help is greatly appreciated!
Hi @ILL001,
I believe that creating custom RealFlight aircraft requires a highly skilled and highly motivated expert in 3DS Max. That’s definitely not me 
Although I am beginning to learn Fusion 360 for use in designs for 3D printing.
Your RFX import problem seems odd; it doesn’t make any sense that it would complain about caipirinha2_EA regardless of what you try to import. Perhaps you need to delete something first?
Tilting motors (in the right direction for the frame type) can provide additional yaw authority (which is bodyframe roll for a tailsitter), but you may find that control surfaces become necessary as airspeed and aerodynamic forces increase.
HI kd0aij,
thanks for the quick reply!
For me, it is rather not a question of skills and motivation. I worked through the custom plane design process of xplane 11 allready, which seems to be in parts similar to rf, so I gues I know what to expect.
However, due to the lack of proper information, I find it somehow harder getting into it.
… So when building a tailsitter quad +, controllsurfaces are optional to some degree even in fixed wing flight?!
For this target, the word “quick” is wrong. 
Here some links to get started:
http://www.knifeedge.com/KEmax/tutorials.php
http://help.autodesk.com/view/3DSMAX/2015/DEU/?guid=GUID-E9E0A683-AEB1-4A0C-807D-F18F321C026C
For the RF8/9 Editor I did not finde information, just learned by doing with trial and error.
RF8 has an issue in Win 7 and Win8, that it crased when returning form the Editor back to RF8. Or when something is not perfect even when loading the airplane whithout any error message. And no support from Knife Edge.
So I had to modify something and to restart again and again and again. When it worked, it seemed that I modified the right thing. Finally I got it, after about 2 month the whole day. Easier to build a model in reality serveral times after a crash.
sounds fun! 
thanks for the provided information!
There are several examples of quad tailsitters with no elevons, such as the XCraft Xplus1. There’s even a Realflight model for the XCraft, and you can experiment with it or disable the elevons on one of my models to see how well it works.
@kd0aij
Tilt Angle for Talilsitter
Sorry I disappeared for bit. I had to travel for work unexpectedly.
Question: I’m playing around with my design… angle of attack for the wings and angle of Motor mounts… Is it possible to adjust the angle (specifically the 90 degree setting) to a different number… say 50 or 55 degrees (hover being 0degrees to 55degreees full transition to forward flight)? What parameter line would I change if possible?
Thanks
Tim
That 90 degree rotation for tailsitters is hard-coded in QuadPlane::setup()
But I think you could accomplish what you want using Q_TRIM_PITCH, which offsets hover pitch from 90 degrees (relative to FW trim).
What is the design motivation for not using 90 degrees?
I’m trying a design that would angle the wing mounted motors up 30ish degrees… to allow the wing to have STOL airflow/lift in slow forward while still in quad mode before transition to Fast Forward Flight. Might not work, but I’m curious to see what the handling characteristics will be. This way it won’t hover with the front wing so high above the rear wing and help me with Forward Flight CG and battery placement.
Q_TRIM_PITCH — For example…I would set the hover trim so the board thinks it needs to be pitched over 30degrees to maintain level hover…then to pitch over transition to 90degrees, board only pitches over an additional 60degrees of actual pitch over to level forward flight (90degrees)? Am I looking at this correctly?
Tim
I think so. I think you’ll need -30 degrees of trim to hover with the motors vertical, although I’m guessing you’ll need more than that to hover in place, since the wings will deflect the airflow.
Agreed… I will give it a try and let you know!
T
How is the progress and what are your experiences with this project?
I mentioned some post earlier the function “Pause at hight” in the program Cura to be able to insert a.g. sections in a fuselage. In the meantime I found where this is hidden in the actual version. (4.5)
Here in the Menu bar: Externsions / Post Processing / Modify G-Code / Add a script / Pause at hight.
It’s possible to pause serveral times/hights.
Still waiting for better wether conditions for my Copter-Tailsitter Tests. (No wind, not frozen, no rain)
Thanks for the tip on pausing a print. That should come in handy some day.
I finished building the model Z last week, but haven’t been brave enough to fly it yet:
printed in PETG, airframe weight 460g
motor: Turnigy D2822/17 1100kv
prop: gemfan 9x6
flying weight 790g with 3S/1300
55 g/dm^2 = 18 oz/ft^2
76 W/lb with 1100kV and 9x6 prop
It looks great on earth with this color, but may be difficult to localize in the air.
RTL will help a lot in this case. 
Good luck for the maden flight.
@kd0aij
Hey Mark and ALL
Getting the Pixhawk lite setup… I understand that transition is controlled by the angel of the FC… What are setting related to the forward thrust motor?… currently I have Servo09 set to 81, but is boost motor active in hover and forward flight, or does it only spin up in transition? Is there a way for it to be on all the time and just the quad motors shut down when I reach my transition angle and the timer activates?
I would like to explore both options… boost motor on supporting hover thrust… and boost motor activate in transition.
Pic attached: haven’t installed the forward thrust motor yet… It will be mounted on a pillion above the wing in between the tail struts. Still developing this model as a tailsitter… and adjusting my pitch over angel as we discussed. Motors are angled up 30degrees.
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