ORIGINAL: The Big Kahuna
Built a 15 size Peacemaker with profile body. Goes like hell but when I put it into a loop it flies in a large loop circle anf seems to fall in on me (bloody thing chases me around the padock) I have the engine offset 2 Degrees pointing to the outer of the circle and I have a rurrer set according to the plan. No wing warp is visible. Any ideas?
Prima facie, if it flies fine upright with strong line tension for class, it sounds most like you do have a warped wing which is causing the model to roll in on you as you enter the inverted phase of your loop. Once that occurs and you start to lose line tension, well....you already know the rest.
But you say there's no wing warping. Examine your CG. If it's too far aft and you are executing the manoeuvre by abruptly jamming in lotsa/max elevator, especially with excessive throw exacerbated if the outer wing has any washin, it'll be prone to stalling at the outer tip and characteristically rolling in. If it's OK, the other contender is wing/fuse alignment. If the fuselage body is misaligned to the wing (not square) so that the outside wing leads, aerodynamically it will develop more lift such that it creates a rolling moment inward with subsequent effect upon line tension, but this occurs both upright and inverted. If you have inadvertantly built in an incidence angle rather than having the wing set in parallel with the thrust line, this can set up rolling moment if there's sufficient lift differential inverted vs upright to create an inward rolling moment. But looking at other possible contributary causes. If you've set the line exits as per plan, then they won't contributory/a cause of the symptoms you describe.
Presumably you are flying it on 52"' lines of no larger diameter than .015".
Secondly, when you commence your loop, you are commencing it leeward or as the model is just past the downwind side of the circle?
Thirdly, what .15 engine are you using, what prop have you fitted to it, and confirm you are tuning it so it develops its peak power. ie: sufficient power to execute te manoeuvre with that model.
Finally, what does your Peacemaker weigh RTF without fuel (dry)? The Peacemaker has 300in² of area and a generous section, so it will carry bloat (excess weight) fairly well provided the engine has sufficient grunt.
If you build 'em light, there's nothing in the classic pattern a typical cross-flow or Schnuerle ported PB .15 glow (Enya, OS or TT) powered Peacemaker can't do on 52' lines in reasonable wind conditions. Along with Modelhob's Smousen, George's venerable Peacemaker is one of my two favourite sport profile models in class.