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  #16  
Old 12-08-2011, 06:39 AM
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Just for the record, I'm finding I have to set the back torque to around 70 and the prop wash around 115 on the 3D swap content I've worked on. The increased prop wash on the tail feathers is also helpful for flat spins. All have been large or giant scale aircraft. Flex, I think Jim is working on it. He has to figure out exactly what the problem is before he can fix it. It could be a combination of problems. If they do tweak it, they have to do some testing to make sure they didn't adversely affect another flight mode. There is no EASY button.

Last edited by td9cowboy; 12-08-2011 at 07:33 AM.
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  #17  
Old 12-21-2011, 11:50 PM
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The problem is you should NOT need to make that adjustment AT ALL.

I am due to make a presentation at our February club meeting, so I elected to show people how to model a plane's physics in RF6.

To that end I selected this little foamy which I recently purchased...

Click me

I got the specs right and adjusted the everything in the sim as per the plane.

I got surprisingly accurate behaviour ( more so than before BTW ) EXCEPT for ONE THING... prop/wash-torque roll.

If you check out the video in the above link you'll see that the plane can easily be launched into a harrier/torque roll by hand and the pilot has absolutely NO problem holding the plane in a prop hang as he flies it around completely stalled.

The sim behaves well, except the plane cannot hold against wash/torque the same way without my performing adjustments similiar to what you said.

Ergo the upgrade improved wing lift stuff greatly but damaged the modeling of prop/wash-torque roll.

In effect I side with Flexible on this...


However Flexible, please be aware that this is a TABLE DRIVE simulation.
No fluid dynamics type of modeling is done for the physics per-se, what you see on the smoke is mostly eye candy and should not be taken as indicative of what is actually going on... these are just numbers after all, not an "ether" through which the plane is actually flying...

Sometimes the emulation is so good we forget that some things simply have no meaning as a way of looking for deviations from behavioural reality off other things.

The sim may be modeling prop wash exactly as Jim indicates, but the smoke particles could move at an angle 90 degrees to that, and the physics emulation may still be correct....
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Last edited by opjose; 12-21-2011 at 11:56 PM.
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  #18  
Old 12-22-2011, 09:57 AM
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I have made this test in real life. The red shows the Prop wash of my 104" wingspan Texas Extreme 260. There is some amount of Prop wash moving over the wing tips.
This gives you full control, even in a hover, or in Harrier roles.
Go back and read Jims remarks about there Prop Wash cone. It becomes elongated, and does not expand out over the entire wing. I don't care about the inner and outer rings of RF Prop Wash, that is not the issue. The Prop Wash, MUST cover the Wing Tips, or it is not real world, and compromises performance. I proved it in RF using the plane that I cut the ailerons off just be yon the prop Wash line, it made no deference.
If I still had a big plane, I would post the test. Some one do the very simple test, using a big plane. Use a 35% or larger aerobatic plane. Use masking tape to stick 6" pieces of crate paper along the trailing edge of the wing. First piece just outside the fuse. Put them a few inches apart, all the way to the wing tip. Run a tie down around the enfonage, and anchor it to the ground. Run the power to full. Take a pick and post it. The prop wash is full next to the fuse. There is still some prop wash at the tips.
Prop Wash has everything to do with extreme flight, even the helies are deficient.
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  #19  
Old 12-22-2011, 06:21 PM
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Originally Posted by flexible
Prop Wash has everything to do with extreme flight, even the helies are deficient.
There IS NO SPOON!

That the simulated plane does not behave as we would expect is a given, particularly since you've pointed and isolated things so well.

Jim mentioned last year that the simulation subdivides the wing area/effect calculations into four or so segments. It may well be that the tips fall outside of the segments that are included in the math.
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