Want to build a wrecked 4 star into a better flying machine, do I have my plans right
#1
Thread Starter
Want to build a wrecked 4 star into a better flying machine, do I have my plans right
I have a broken fuse nearly fixed and I have doubled the size of the rudder and elevators. Now i need to build the wing. I am thinking 0 dihedral and removing one bay from each end..I believe that is what I have heard works well. I am also going to use wider strip ailerons..at least 50 percent.. I am really wanting this thing to fly well.
Have I left anything out or am I off on some of the mods?
Have I left anything out or am I off on some of the mods?
#3
Thread Starter
Tom I am no 3D guru...but I have been known to attempt a hover now and then
My understanding is the inner part of the strip ailerons get a lot of prop blast that allow them to be more effective in a stall type situation...
I have the basic wings framed, and the fuse is taking more work than expected. I did throw in some strong but slow servos ...so I might not be lightening fast..but I should be able to hold a lot of throw in the control surfaces.
My understanding is the inner part of the strip ailerons get a lot of prop blast that allow them to be more effective in a stall type situation...
I have the basic wings framed, and the fuse is taking more work than expected. I did throw in some strong but slow servos ...so I might not be lightening fast..but I should be able to hold a lot of throw in the control surfaces.
#4
I'm no 3D guy either. I just thought that the barn doors would be look cool.
I'd be tempted to modify the airframe to look like a psuedo German fighter, just for grins.
No matter what you do, it'll be a fun project.
I'd be tempted to modify the airframe to look like a psuedo German fighter, just for grins.
No matter what you do, it'll be a fun project.
#7
Thread Starter
You know a funny story.. After I bashed mine into a ME109, I helped a friend bash one into a Spitfire.. we went to Sig's flyin.. and HIS ENDS UP IN THE CALENDAR the next year ! After I designed all the parts to make it the Spit.. he got the glory !!!! ...
https://www.youtube.com/watch?v=2L8nerJSsAM
https://www.youtube.com/watch?v=2L8nerJSsAM
#8
Another nice model !
I could see a bunch of guys getting together, and making similar mods. Flying them together would be a blast.
I'd probably have to move back to Iowa, to find enough builders to join in. There certainly aren't many around here.
In the vid, is that I-80 in the background ?
I could see a bunch of guys getting together, and making similar mods. Flying them together would be a blast.
I'd probably have to move back to Iowa, to find enough builders to join in. There certainly aren't many around here.
In the vid, is that I-80 in the background ?
#9
Thread Starter
Yes it is Tom, its what we used to call NORTH FIELD.. it is or WAS immediately west of Morningstar Airport. Morningstar is still there.. for now. But our old sod farm field is now a lake after the gravel pit sifted thru it for several years.
#10
Sounds like fun. I have the old Contender 60 with a low wing that is pretty narrow for the rest of the size/weight and no dihedral at all (one piece spars) and it is a great flier. I did bring the tips of the wings up to be flush with the upper surface (like having a tiny bit of polyhedral) that was mentioned in the plans as a solution to a dutch-roll issue. I also added about 40% more rudder than the original plans. You may or may not need something like that.
With a computer radio it's easy enough to mix in a tiny bit of rudder with the ailerons to do the same thing if you want to just leave the wings "chopped".
With a computer radio it's easy enough to mix in a tiny bit of rudder with the ailerons to do the same thing if you want to just leave the wings "chopped".
#11
I have a broken fuse nearly fixed and I have doubled the size of the rudder and elevators. Now i need to build the wing. I am thinking 0 dihedral and removing one bay from each end..I believe that is what I have heard works well. I am also going to use wider strip ailerons..at least 50 percent.. I am really wanting this thing to fly well.
Have I left anything out or am I off on some of the mods?
Have I left anything out or am I off on some of the mods?
Keep the strip ailerons.Seal the aileron gaps with tape or covering-film.
Reduce dihedral to 2 degrees in each half-span. If you use zero dihedral you will have adverse roll upon rudder application (right rudder => left roll; left rudder => right roll),
Lower the stab ~1 inch. This reduces the tendency to pitch toward the belly upon the application of rudder.
Add a sub-fin from wing trailing edge to the rudder post, and extend rudder down to match the bottom of the sub-fin. If you do 4-point rolls, the extra side-area helps hold the knife-edge position.
Balance the plane side-to-side.
Last edited by gyrocptr; 06-26-2014 at 09:29 AM.
#12
Thread Starter
Gyro, I was to fast..or you were to slow ! dang I have the wing built and covered with zero dihedral.. I also made some removable air damns to mount out on the wingtips..just because hahahahah
#13
If you would like to counteract the adverse roll, you can do the following: configure the tip plates so that they extend above the wing top-surface about 1-1.5 inch, with zero tip plate area extending below the wing bottom-surface. If the adverse roll persists add more tip plate area above the wing. If the plane rolls in the same direction as the rudder application (proverse roll), reduce the tip plate area above the wing by small increments until the plane only yaws with rudder application (no roll in either direction).
#14
Thread Starter
Your knowledge of airflow scares me
I would have never even guessed on those tips effects to the roll and yaw. Or the ability to adjust them ... I will see how this thing flies and hopefully there won't need to be TOO much experimentation !
Thanks for typing out all the hints and tips...
I would have never even guessed on those tips effects to the roll and yaw. Or the ability to adjust them ... I will see how this thing flies and hopefully there won't need to be TOO much experimentation !
Thanks for typing out all the hints and tips...
#15
Thread Starter
Well as usual I trimmed out the plane on a 20-30 mph gusty day !
Why? I don't know..its always nasty when I get out there to trim a new plane.
I didn't get to enjoy the feel of what it will do on a nice day.. but it trimmed out fairly easily in the wind. I just sort of got blown around for awhile as I fought the gusts, Then I lined up for the final...I could tell the shortened flat wing really tracked straighter than my old 4 star...
I got it down into ground effect and kept fighting the wind but eventually got a nice decent landing.
It will be interesting to try in good conditions and see what I have..
Why? I don't know..its always nasty when I get out there to trim a new plane.
I didn't get to enjoy the feel of what it will do on a nice day.. but it trimmed out fairly easily in the wind. I just sort of got blown around for awhile as I fought the gusts, Then I lined up for the final...I could tell the shortened flat wing really tracked straighter than my old 4 star...
I got it down into ground effect and kept fighting the wind but eventually got a nice decent landing.
It will be interesting to try in good conditions and see what I have..
#16
Thread Starter
Gyro I sealed the control surfaces, and have been trimming the tip board surfaces below the wing each time I fly it.. I have it working much better ! I trimmed a small amount again today.. Thanks for the help..it is working better.