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Posted by Knoll53 | Aug 30, 2014 @ 11:03 PM | 4,900 Views
Today found a little choppy lift and just put the nose down a bit and let it cruise............this plane is much happier when it's moving. The flaps are 2" shorter now and happily are pitch neutral. They are an absolute requirement for a wing this skinny. There is a learning curve for the tiny flight envelope, but I'm beginning to get it.

Razor's Edge in choppy lift (2 min 1 sec)

Posted by Knoll53 | Aug 24, 2014 @ 07:33 PM | 5,227 Views
Down right windy today which apparently make the local wildlife frisky.
Air Plank and the hawk (2 min 14 sec)

Posted by Knoll53 | Aug 24, 2014 @ 07:04 PM | 5,114 Views
Again some condors flew through in mid afternoon. Only got a few glimpses with the new camera.
California Condor & Air Plank (1 min 21 sec)

Posted by Knoll53 | Aug 23, 2014 @ 11:28 PM | 4,845 Views
Posted by Knoll53 | Aug 17, 2014 @ 08:11 PM | 5,354 Views
Posted by Knoll53 | Aug 17, 2014 @ 07:40 PM | 4,578 Views
Toyed around with a variety of CGs and elevator throws today in the calm hot air of Soberanes Point. The best performance and elevator response is with a very aft CG which brings less than stable handling, but so far, that is my comfort zone with this plane. This flight has the aft CG and you see that it is not exactly on rails. Video cut short due to autofocus problems. Going all manual focus next time.

Razors Edge at Soberanes (0 min 33 sec)

Next up to completely glass the wing in order to combat flutter.
Posted by Knoll53 | Aug 16, 2014 @ 11:44 PM | 4,813 Views
Found an hour today before work and got some testing in after the flap and pod rekit. Nice calm conditions at 9am. Had to rework the CG because the reference mark was lost. Trying different CGs today shows that this plane really performs better with an aft CG. Also, the tip stall is not a problem with a forward CG and IS a problem with the high performance aft CG.
First Bungee (4 min 57 sec)

Short story is that the flaps are pitch positive, as in a lot of nose up. After a few flights, settled on 15% down elevator mixed into flaps to tame things down but am surprised the Nickels formula is so far off. Checking my work now.
Flutter and Flaps (0 min 43 sec)
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Posted by Knoll53 | Aug 12, 2014 @ 08:23 PM | 4,432 Views
After a few flights, it's clear that if any wing could benefit from flaps to slow the action down, it is this one. New servos are on their way.....

If it turns out that the flaps mitigate the stall behavior, I'll mix them into the elevator.

Flap sizing based on Nickel's formula.
Posted by Knoll53 | Aug 10, 2014 @ 04:48 PM | 3,687 Views
As expected, this tiny thin wing is not shy about stalling and falling out of the sky. The flight envelope is plenty big, but when it DOES spins you had better be ready. Today proved that it will spin to left every time. Flying with a light touch on the elevator is the solution. The elevator response is very response for a swept wing so I think that the CG is back far enough. For awhile, flew with 2 quarters taped to the nose and performance was noticeably less, i.e. could not soar these light conditions.

Razor's Edge light lift (2 min 27 sec)

Posted by Knoll53 | Aug 10, 2014 @ 10:47 AM | 3,797 Views
Here's a tiny Rhinohide covered flying wing. This one came in at 14.5 oz. AUW or 8.7 oz/s.f., almost a floater but with a 4" chord it moves out nicely. This is the first flight right off of the building board. It has a dramatic spiral dive tip stall that can be "activated" by a variety of moves. Proper CG and limited elevator deflections tame it nicely for slope flying.

Razor's Edge First Flight (0 min 55 sec)

Posted by Knoll53 | Jul 17, 2014 @ 12:49 PM | 4,520 Views
Inspired by a short discussion, here's my approach to a forward swept wing prototype. It features single surface elevator and flaps with a rudder for roll and yaw. Still thinking about how much dihedral to use. Some where in the 3 to 5 degrees range.

What I like about this configuration is that for nose up the elevator/flap deflects down, thus increasing camber and AoA. Good for slow thermal flights and in reverse good for fast slope flying.

Wing skins
PolyC and glass (1 min 16 sec)

Food Wrap at fuse did a nice job of controlling loose glass edges and compressing all. final finish needed minor sanding to remove small ridges.
food wrap on layup (0 min 52 sec)
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Posted by Knoll53 | Jun 24, 2014 @ 10:56 PM | 5,655 Views
I've been flying a Zagi lately and the only thing it needs is the option of high wing loading.
Posted by Knoll53 | Mar 24, 2014 @ 09:21 AM | 6,400 Views
Looks like I'll get a stab at a rudder enabled, thick plank with dihedral with a rebuild of a Saracen. I'm adding wingtips, a new fuse, tail and elevons. Was surprised to find that the fuse plug became quick stiff after one coat of Poly C. I'll glass right over the plug without tape it first, so the hope is that the Poly C with reduce the amount of epoxy needed.

Saracen redo (0 min 17 sec)

Posted by Knoll53 | Feb 19, 2014 @ 12:47 PM | 5,480 Views
Using the TLAR method for pitch neutral flaps on a curvy, hard to analyze wing.
Posted by Knoll53 | Feb 08, 2014 @ 01:47 PM | 7,430 Views
Inspired by the FootLoose's big brother.

Posted by Knoll53 | Feb 01, 2014 @ 01:02 PM | 4,209 Views
Inspired by the Wind Freak, my version of a Floater Plank.

Posted by Knoll53 | Jan 11, 2014 @ 02:45 PM | 5,777 Views
I've yet to build a light here's my shot at it.

Size is based on my preferred flight pack. That is, in order to carry this flight pack, I'll need a 60" span. I'm treating this as a plank, so no twist and one degree of dihedral.
  • 4 AA batteries and hitec 82MG servos
  • .5 taper ratio

With the wing sweep and the very light winglets, the goal is no nose lead.

Posted by Knoll53 | Oct 19, 2013 @ 11:09 AM | 4,465 Views
Dave Alchins Helios on it's maiden flight.