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Archive for August, 2014
Posted by Knoll53 | Aug 31, 2014 @ 09:44 AM | 4,695 Views
Final layout with field tested "nearly" pitch neutral flaps.
Posted by Knoll53 | Aug 30, 2014 @ 11:03 PM | 4,897 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 | 5,223 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 | 5,110 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 | 4,840 Views
Posted by Knoll53 | Aug 17, 2014 @ 08:11 PM | 5,350 Views
Posted by Knoll53 | Aug 17, 2014 @ 07:40 PM | 4,574 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 | 4,809 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)
...Continue Reading
Posted by Knoll53 | Aug 12, 2014 @ 08:23 PM | 4,425 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 | 3,684 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 | 3,794 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)