the 15x6 has worked before on my maiden flight... but the problem then was my pickup... it got stuck in the corner... at least I was in the air for a while but then it cut, had a safe landing back then cause I was very high and had speed... after fixing the problem, making the line a little bit shorter in the tank and also cleaning the HSN valve... taking out the whole carb to clean the LSN... took it apart complete... the tune sounded good at least... so I don't know... is there a specific size or type of fuel line to use? I use Omega 10% fuel... I don't want to try my luck anymore and take off... too scared, cause the same happens each time... I have a 13x8 prop on there now, but I have no idea what will happen... why is everything good on ground? good response, all power is there no bogging... but when it gets in the air it bogs and dies?