Back to the original subjects, I had a computer glitch (Windows is not very polite to Linux.  After 43 years in the computer business I should know better, both about accessing another system from a Windows box and making sure my backups were backed up.) and lost most of my drawings for the F2A.  Fortunately, the cut sheet drawings were on the machine that runs the laser cutter.  I have to redraw the plans and the skins.

The photos show a wing made from the final version of the F4U drawings.  For the time being, the F4U no-cal is available only to the members of the Blacksheep Squadron.

For structural reasons, the Cutlass wing is not that extensively keyed.  The redraw of the F2A may have a similar wing structure.

Looks great!  I really like it.  Well done.

Tom

Ditto what Tom said.
It's interesting to follow the development of a model.

Things didn't go quite as I had expected this past week.  The Viggen is not yet finished with its rebuild and may have to take a back seat to more urgent projects for a while. 

The Cutlass has been slightly redesigned into a "production version" with some improvements in the structure.



The outer wing panels have a reflexed airfoil, the elevons are larger and in almost scale position, the outer wing panels have a small amount of dihedral, and the nose piece, tail piece and canopy outline have been redesigned for greater strength.  The new prototype was made of "contest grade" wood to see how light I could get it and a wooden prop was substituted for the Peck prop on the original.

I flight tested it at Stonehurst this morning with the following results. 

The production kit will not have contest grade wood.  The few grams saved are not worth the structure being so fragile.  It was hard to make adjustments without breaking something.

Although the CG is in exactly the same place when trimmed, it is a bit harder to trim with the new wing.  The up elevator needed is much less with the reflexed airfoil in the outer wing panels, the model is much more sensitive to small changes in elevon position.

It can be trimmed for a very floaty glide at the risk of a stall and spin when the motor runs out.  This condition did not exist in the version of the wing without dihedral.  I flew the original for direct comparison.

Stable powered flight as well as turning are adjusted by adjusting the thrust line.  I may have to change to a different prop hanger since most people will probably find the mandrel wound wire prop hangers, that I have been using, a bit too stiff for fine thrust line adjustments

The wooden prop I was intending to use is lighter than the Peck prop, but the reduced thrust does not offset the weight.  I'm looking at another wooden prop design, but for the moment, kitted it will probably have a Peck prop.

There was a contest at Stonehurst today (Arf-a-Senator no-cal) so I didn't get in a lot of test time, nor time for any videos, but when it is properly trimmed it just goes up to the ceiling and cruises around.  Most of the trim problems I had were cause by breakage, so there is a bit more redesign for strength yet to go before I finalize the plans.

Videos from Stonehurst next week.

It was a dark and stormy night...

No, really, it was.  Besides I've wanted and excuse to start something that way for a long time.  

The fact that it was dark and stormy had nothing to do with the indoor flying at Luther.  The fact that I had reduced the left thrust adjustment to take advantage of the larger room did.  With the turns opened up the Viggen flew into the ceiling, which is a wooden, geodesic barrel vault at Luther, breaking the wing, and the Cutlass managed to hit yet another basketball backstop, breaking the propeller in half.  The videos will have to wait until next Wednesday at Stonehurst.

By the way, the largest, legal no-cal on record was a Douglas X-3, flown in a contest a Luther a while back.  With a 16 inch wing span, the fuselage was 47 inches long.

Outstanding Viggen....

Look forward to the video....

Tom

Methinks that I have seen this silhouette airplane somewhere before!

The Viggen is coming along.  On a model this size I can't cover tightly dry, so unlike the real indoor experts, I have to shrink the tissue.  The canard and tail were no problem.  The fuselage and wing were another matter.  I had to pin down the fuselage on the plywood plank that I usually use for wings.



I set the pinning up then sprayed the fuselage with rubbing alcohol and had a bit of a fire drill (No particular ethinicity specified.) to get it all pinned down before the tissue started to shrink and turned the fuselage into a pretzle.

The root chord of the wing is over a foot long so I had to use a two foot square sheet of plywood to pin it down.  The planks and plywood that I use for tissue shrinking and other utility functions are stored convinently in a slot between the two movable sections of my workbench, just to the left of the pictures.



I managed to get a few more details on it before I had to turn to other issues, but it will be finished tomorrow and flying at the OFFC meeting next Wednesday.  I'll definitely get some video.



I showed it to my wife and she said, "It looks like a cartoon."

Since a No-cal IS a cartoon of an airplane, I suppose that is a complement.