profile pathfinder

im thinking about building a pathfinder for a supertigre 51 would this be to much motor?

>im thinking about building a pathfinder for a supertigre 51
>would this be to much motor?

Just my opinion. I went flying this weekend and there was one I watched do the pattern with a OS40 FP that was modified for the 2-4 break. I have also seen Gordon Delany fly his with a OS 40 FP. He wins profile 40 regular with it or one of his buddies. Yeah, I think the ST 51 is a bit much. I have also seen them perform nicely with a ST 46. The ST 51 will fly a 60 size ship with no problem. Dirty Dan used one in his Impact for awhile and Bill Little says he used one in one of his 64 ounce ships. Sure it will work, just not my first choice do to the power and weight.

Brad,
I just completed a Brodak Pathfinder this spring. Covered with Ultracoat and with Lustercoat on the fuselage it weighs about 47 ounces. I power it with a stock OS .40LA turning a RevUp 10x6 wide prop. The engine will turn up to about 12,000 rpm but I fly it in a rich 2 cycle at about 10,700 rpm. Flying on longish 66 foot long .015 lines the plane pulls hard. Even on windy days the plane stays out tight (even overhead). Based on my experience, I would think the ST .51 would be overkill. Enjoy your Pathfinder.
DennisV

i like the long lines . this is my 2nd year flying since the 70s last year somebody gave me a 60 size plane i put a max 50 in it and flew it on 70 foot lines i loved the it flew jim cole said i seemed more comfortable with it the i have my nobler arf. it seem to fly slow and plenty of line tensition. sorry cant spell that word you know what i mean. and i was lookling to build a 60 size profile but cant find a kit. i like the idea of staying with 15s did you try longer lines on it dennis. im a big man so i like the plane to pull hard.

>i like the long lines . this is my 2nd year flying since the
>70s last year somebody gave me a 60 size plane i put a max
>50 in it and flew it on 70 foot lines
i like the idea of staying with 15s did you try
>longer lines on it dennis

I bought 70 foot, .015" diameter lines from Lone Star Balsa and tried them. The plane flew OK but it seemed a wee bit much for the OS .40LA to pull. So I cut the lines back to 66 feet and the Pathfinder flies great on them. Compared to 60 foot lines the 66 foot lines give me slower lap times and more time to react (a good thing for an older f_rt like me) .
Dennis

P.S. With a SSW Leonard Neuman tongue muffler on the OS .40LA my Pathfinder CG came out exactly per the plans location. No need to add nose or tail weight - I like that.

I think that the ST 51 is way to much for the Pathfinder. I have an LA 46 in mine and it flies a little fast with the 46. A 40 might be better, but i like the LA 46 in it. Longer lines would definetely help on it if you used the bigger engine, I use 70' on my Accentor and it works great, 60' on the pathfinder though.
Ryan

I fly with Gordan a lot. I also helped a small bit o the development of the Pathfinder as it now is. All of the Pathfinders we fly here in Salt Lake are powered by .40 size engines, and they perform quite well even at our altitude. (4300 feet)

Of course, you could power yours with the .51, but it will be overpowered, and need to be run below it's potential.

If you're scratch buiilding one, why not take the plans to Kinkos and scale it up to about 700 sq. inches? You should consider a bit more beef in the fuselage for the larger engine, but I would venture that it would make a nice combo on the larger engine.

Just a thought for you to consider.

now thats a good idea how much bigger percentage wise would it have to be blown up and you said to beff up the fuselage what maybe make it 3/4 inch instead of 1/2inch? hey thanks guys for all the ifo this realy helps me out.

I just got in from flying my PF with a SSW Tower 40. With the 40 it is a horse. Lots of line tension, turns on a dime and gives you change. FP/LA 40 is plenty. Mine balances perfectly with a tongue muffler, too. If you go to the 51, you'll also need (by the AMA book, anyway) to use .018 lines and give up some advantage there.

BTW, does Gordan have any drawings of the full-fuse PF I saw a photo of?

First, to answer the question about percentage of scale up to get to 700 sq inches, It would depend on whether your planes were of the first version, published in FM, or the Brodak version. they have different wing areas, and construction. I would suggest using the plans from the Brodak version. If you don't have them, I can supply a set aready scaled up for a modest fee.

To scale up, you ask the question, 700 sq inches is what percentage of the area on the plans you are using. 700/x. Then use the square root function on th number you get to get the actual scale factor you'll need to enlarge the plans.

So if you're using the Brodak version, it has 620 sq inches of area.
it'll be the square root of 700 divided by 620, or a scale factor of 1.063. This is a rounded number, but it'll get you there.

3/4" fuse would work fine. Better yet, Balsa framed, foam core, 1/64" ply on both sides.

As for thesecod post re: the full bodied Pathfinder, I do have the plans for that one, and can supply them, once again for a modest fee. I built the one you probably saw the picturte of, back in 94. I still have the plane, though I've retired it from active service. I used a strong running modified OS .40fp, but an ST 46 or 51 would be a great match.