Originally Posted by minirotor

Interesting.
I moved my c of g 4-5mm behind the spar one day (to see what would happen)
The glider flew surprisingly pretty good (elev a bit more twitchy of course)
But what really surprised me was I still had to add a bit of foreward stick
when inverted

Check the incidence of the horizontal stabilizer.

Either due to design, molding, or damage/repairs, it's possible you have some positive incidence (meaning the leading edge of the stab is lower, when viewed from the side, than the trailing edge, resulting in a permanent "up elevator" input).

In addition to the inverted test you describe, you can also see the effect of this on uplines - the plane will tend to pull to canopy a bit.

Many thanks to Steve and Tony for the file and the tweaked file and to the rest of you for advice. My Ahi is now set up *almost* as I'd like it. I'd still like to get a dead-band around center throttle stick, but now that I can switch the 4-axis mix off at will I'm ready to give her a test fly. Wind is iffy at a local site tomorrow, or forecast to be quite good a mere three-hour-drive or so away on Sunday . . .

Also, pawed a DX6e in the LHS today--not a bad feel at all for the price point. Probably will pick one up as a worry-free, leave-it-in-the-truck sloping radio.

Originally Posted by surfimp

The roll inputs are the part where I maintain energy and airspeed in the slope soaring context

Yes, visually it looks similar to a loop, but aerodynamically it's just a very large diameter inverted barrel roll.
It's flying a spiral through the moving air mass.
When I use the word "loop" in context of the aircraft's performance doing inside or outside loops, I'm speaking in aerodynamic
terms rather than visual, and yes a true aerodynamic loop usually takes more energy to pull off. That said I'll bet you could,
if you chose to, do endless inside loops perpendicular to the slope even in your narrow little lift band, but I
suspect it could not do so inverted. That speaks to an aerodynamic quirk of this plane's airfoil, which
has been my point all along.

And yes I've read what you said about not choosing to conform to pattern rules. I am not advocating
that anyone should be forced to one or the other. I mix em all together, all the time.
e.g. I like to do a variation on your spiral loop where I don't complete the roll over the top
but let it stay in a knife edge orientation throughout the top arc, so it starts the next downline inverted,
which I carry across the bottom, back up the upline, knife edge across the top, and start the
next downline upright again. It draws a nice round circle in the sky occupying the same space
as your spiral loop, but every other cycle is inverted. It relies heavily on the wind, and probably
isn't even possible to represent in any pattern notation.

And I guess my point is that, considering the Ahi is using a lightly modified version of the Libelle airfoil (source: MR), which is far from anything we'd consider a "true" aerobatics airfoil, its outside performance - while not comparable to a true aerobatics airfoil - is still quite good.

Assuming something better than marginal lift, I'm sure (because I have done them, though don't recall if I have it on video) it would easily perform the straight-out loop inverted (caveat: you have to have airspeed and good technique), but I agree it will probably struggle to do them consecutively, except in very good lift. However I have also shown that you can certainly work a lift band to perform consecutive negative G figures that look very much like loops to all except diehard precision purists and those with a point to make

With that said, although the inverted performance is not on par with something like a Wasabi or Voltij (or Le Fish for that matter), it's still quite good, and you can do a lot inverted. I mean, I think this is pretty conclusively demonstrated by all the many different flight videos out there.

We're really talking about that final like 5% of performance, but my point is that it's very good, both upright and inverted, especially when a small amount of snapflaps is used. But any glider, no matter how good, is going to have its limits, and the Ahi certainly has these as well.

EDIT: I would like to let the record show, Ian, that we are well overdue for some more aerobatic video content from you, good sir. I miss seeing you shred!!

Originally Posted by surfimp

Check the incidence of the horizontal stabilizer.

Either due to design, molding, or damage/repairs, it's possible you have some positive incidence (meaning the leading edge of the stab is lower, when viewed from the side, than the trailing edge, resulting in a permanent "up elevator" input).

In addition to the inverted test you describe, you can also see the effect of this on uplines - the plane will tend to pull to canopy a bit.

Thanks Steve.
Yeah it does not look good after too many firm terra arrivals.

I find that you can do continious inverted loops if you continue your down line
to pick up enough enegy (speed) to go over the top again.
You do need fairly good lift and squeeze the best from it while inverted
or you will get lower and lower.
Also a fair bit of reflex (negetive flap) also helps inverted loops a lot.

Originally Posted by Daemon

I'd really like to see video of someone who hasn't modified their tail surfaces, doing continuous outside loops.

Mine can do 3 outside loops, but it is a lot happier doing inside loops.
In the video the outside loops start at about 0.16

David.

7G +/- with Ahi (0 min 34 sec)

Here we go!
The 3 flight modes are now:

Full 4 axis
4 axis with a deadzone centre stick
No 4 axis

Short session with great Ahi! Testflight maded and simply love this guy) Greetings!

Originally Posted by SilentPilot

Here we go!
The 3 flight modes are now:

Full 4 axis
4 axis with a deadzone centre stick
No 4 axis

You rock, dude! Off to the shop . . .

Originally Posted by AndrewID

Short session with great Ahi! Testflight maded and simply love this guy) Greetings!

Nice pictures!

Originally Posted by f3fisa

Mine can do 3 outside loops, but it is a lot happier doing inside loops.
In the video the outside loops start at about 0.16

These are still loops performed crosswind to the slope - Ian is specifically looking for loops performed into or with the wind, at a 90 degree angle to the slope.

Anyways, besides that specific requirement, I think it's well-demonstrated that the Ahi has very good outside performance, and the claim that "it won't consecutive outside loop" is valid only for very specific definitions of "outside loop"

Originally Posted by SilentPilot

Here we go!
The 3 flight modes are now:

Full 4 axis
4 axis with a deadzone centre stick
No 4 axis

Originally Posted by Xeric

You rock, dude! Off to the shop . . .

+1!
Thanks!

Originally Posted by AndrewID

Short session with great Ahi! Testflight maded and simply love this guy) Greetings!

Excellent pictures!


Dave

Originally Posted by dawsonh

Will do!

Dawson

We -I!!!- are looking forward to that file. Thanks!!!

I went to Point Fermin in San Pedro today and met up with a couple of guys who had new Ahis. One of them, the legendary Carl Maas Jr., had even downloaded the AirWare file for his new DX6e, so I got to test it "in the wild"...

Worked perfectly! I believe it needed just 2 or 3 clicks of down trim and otherwise flew great. Stoked to see that happen, for sure

I was busy flying the planes and whatnot so didn't get any pictures, but it was a fun day with good friends I hadn't seen in too long. The Ahi made it happen!