GP Super Sportster 60 Build

Not really bored but I just happened to have started to build a Super Sportster 20 just last night. Near as I can tell, they are virtually identical other than size and some construction details. Decided to build this kit as a sort of warmup to a Super Sports 40 RCM twin engine conversion which will use two Saito .30 engines. The SS .20 will be my 8th kit. Are you going for trike gear or tail dragger? Looking forward to following along with your progress as I build my own.

You need more "stuff" in your shop. You can obviously still walk around in there !

If you've not covered the tail feathers yet, you might consider making the fin and rudder taller.

IIRC the Super Sportster lacked rudder authority in a big way. Been twenty years since I built one, but I remember the thing just didn't respond much at all to rudder input.

Maybe they've addressed that problem in the intervening years, and maybe someone else has had a better experience with that model.

It flew ok, but the rudder didn't seem to do very much.

The most aggravating thing about the SS .60 was that the landing gear wires were undersized and far too easily bent.

That model is best "greased" onto the runway unless you like straightening out wire landing gear and rebuilding the l/g mounting blocks. Many references to the 'bend-ability' of that landing gear can be found in a Google search if you're interested. Ditto for the rudder problem. Cheers, Fred McClellan The House Of Balsa Dust

I am going for the taildragger look. I did not install the landing gear mounting blocks in the wings. I plan to use an aluminum gear mounted on the fuselage. There was a very minor unhappy landing with my PT-19 and it tore the gear out of the wing, since I didn't like fixing it I decided to head off that issue from the beginning on tis plane..

Charlie

Feel free to modify your gear placement, but do be aware that the gear on the Super is VERY STOUT as shown on the plans. I have 2 Supers that are beautiful flyers.

Kev

Hi Kevin, You are the first person that I have "heard" say the Super Sportster landing gear is very stout. Since you have two of them in the air right now that tends to lend a lot of weight to your statement.

However as far as the landing gear modification goes it is a done deal, the wings are built, so there is no turning back now. When I was looking into the plane the one modification that kept coming up in the forums was to mount the gear like the 4-Star series. Of course this could have been originated with a single individual and then it became urban legend as a "required" modification, since it does sounds reasonable. My wing ribs have cutouts in the front and rear and when I trial fit the plywood doubler for the gear mount block it did not look very sturdy. More than anything else though, I was also having trouble figuring out exactly what angle to place the ply doublers at, so it was one of those command decisions to go for the less elegant, but hopefully easier, aluminum landing gear solution.

Once again since you currently have two of these flying I would like to ask a few more questions. If you don't mind making some comments I would appreciate your insights.

What do you think of the suggestion in this thread on enlarging the vertical stabilizer and the rudder ?

For purely aesthetic reasons I am thinking about making the modifications below, if you think either or both to be bad ideas it could influence my final decision on implementing them.

1. Stringers along the fuselage to give it a more old timey look, similar to the PT-19, I don't see any risk here, but if you have comments about this being a bad move in regards to covering or anything else I would like to hear.

1. The other modification is more risky since it involves the stabilizers. The Astro Hog has a Balsa beam that runs parallel to the trailing edge and is centered front to rear, when it is covered it forms some sort of airfoil. I like the way this looks a lot and am thinking about doing it on this plane. I certainly do not profess to knowing anything about airplane design so this one is kinda scary, but at the same time "appears to be reasonable".

Regards, Charlie

I wouldn't go too much larger, but I don't see how 10% or so could hurt. One of my Sportsters has modified tailfeathers, but I don't think they're larger. I didn't much like the "circus" looking empennage that comes stock, so I made some mods. It looks more like a P-51 tail than a Sportster. Straight lines instead of round, angles instead of curves.

| 1. Stringers along the fuselage to give it a more old timey look, similar to | the PT-19, I don't see any risk here, but if you have comments about this | being a bad move in regards to covering or anything else I would like to | hear.

Shouldn't be a problem, just watch out for weight. I didn't mention my third Sportster because it came out well above published maximum weight, and didn't survive the maiden flight. It flew ok under full power, but chop the throttle and it was Instant Stall. Of course, I couldn't forsee this anomoly, an it was three mistakes high before it manifested itself.

| 2. The other modification is more risky since it involves the stabilizers. | The Astro Hog has a Balsa beam that runs parallel to the trailing edge and | is centered front to rear, when it is covered it forms some sort of airfoil. | I like the way this looks a lot and am thinking about doing it on this | plane. I certainly do not profess to knowing anything about airplane design | so this one is kinda scary, but at the same time "appears to be reasonable".

Myself, I wouldn't make a flat stab into a lifting stab. There is the possibility of radically affecting the CoL. I suppose, if you make it fully symetrical it might not affect the flying characteristics too bad. You will HAVE to make sure it is at zero degrees incidence to both the wing and fuse.

Good luck with your project! Keep us posted.

Kev

Thank you, I appreciate your time. Charlie