flyranger
Junior Member
Getting yet another plane ready for Flite Fest 2021, I reached into my archives and resurrected a design from 2013, the Old Fogey. Not content to leave anything alone, I had to make a few mods.
I took the fuse plan, cut it on the centerline and reduced the fuse width to 2 inches. Added V-tail, not because it needed it, but I like a challenge. Plane was uncontrollable in left/right, something I remembered seeing on the original design, something called "Dutch Roll". To make this go away in 2014, I added area to the Fin and Rudder.
Kept the swappable motor mount but raised the aft end up, to set down thrust. Fixed with skewers through the fuse.
Took the horizontal stab and elevator and increased area by 20 percent, score cut and glued for an angle of 110 degrees. My old buddy "Dutch Roll" was baaaaak. Built 2nd fuse and made the angle 90 degrees, which should increase "rudder" effectiveness. Went flying just before a storm in 8 mph winds and stability improved, but still a handful, more than this old man wants!
What the heck, this is foam, right? Added two more inches to the height of the ruddervators and in winds of 12 to 14 mph, tested again with an 1800ma 3s. Almost there, but still a handful.
Set exponential to 50% (yeah, I know that's high, but I did warn you I'm an old man) and reduced throws. Much better, but needs improvement.
Cut the wing tips off and reglued with only half the original dihedral (from 3 inches to 1.5 inches). Moment of truth and she flies!
No more problems. Ran down the battery in high winds with a 20 minute flight.
Specs: 7x3.8 APC prop on a 2218-1180 radial pulling 4.7 amps with static thrust of 24 oz. AUW is 17 oz running a Castle Creations 15 amp ESC.
Wing is unchanged, except for dihedral of 1.5 inches, each wingtip;
After FF21, will rebuild a little prettier, but I'm happy with the design.
Attempted a pusher design using a 3D printed wing mount, but had to scrap that. My lovely wife is getting me a 3D printer for my birthday. Will try again then.
I took the fuse plan, cut it on the centerline and reduced the fuse width to 2 inches. Added V-tail, not because it needed it, but I like a challenge. Plane was uncontrollable in left/right, something I remembered seeing on the original design, something called "Dutch Roll". To make this go away in 2014, I added area to the Fin and Rudder.
Kept the swappable motor mount but raised the aft end up, to set down thrust. Fixed with skewers through the fuse.
Took the horizontal stab and elevator and increased area by 20 percent, score cut and glued for an angle of 110 degrees. My old buddy "Dutch Roll" was baaaaak. Built 2nd fuse and made the angle 90 degrees, which should increase "rudder" effectiveness. Went flying just before a storm in 8 mph winds and stability improved, but still a handful, more than this old man wants!
What the heck, this is foam, right? Added two more inches to the height of the ruddervators and in winds of 12 to 14 mph, tested again with an 1800ma 3s. Almost there, but still a handful.
Set exponential to 50% (yeah, I know that's high, but I did warn you I'm an old man) and reduced throws. Much better, but needs improvement.
Cut the wing tips off and reglued with only half the original dihedral (from 3 inches to 1.5 inches). Moment of truth and she flies!
No more problems. Ran down the battery in high winds with a 20 minute flight.
Specs: 7x3.8 APC prop on a 2218-1180 radial pulling 4.7 amps with static thrust of 24 oz. AUW is 17 oz running a Castle Creations 15 amp ESC.
Wing is unchanged, except for dihedral of 1.5 inches, each wingtip;
After FF21, will rebuild a little prettier, but I'm happy with the design.
Attempted a pusher design using a 3D printed wing mount, but had to scrap that. My lovely wife is getting me a 3D printer for my birthday. Will try again then.
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