I recently purchased a Hanger 9 Arrow trainer, an AMA card, and joined the local flying club. My friend has over 25 years experience flying so he is instructing me with a buddy box.After about 8 times out we have yet to get the engine running correctly, the last time when my friend put his finger over the carb to cut it off it kept running, I know enough about 2 strokes that I knew it was getting air from somewhere it wasnt supposed to. We also had the radio die immediatley after takeoff once, this resulted in a hard landing with nothing hurt but a bent landing gear, I was informed by the hobby store that sometimes interferrence will cause as he put it " getting shot down ". The hobby store owner insisted ,after I repeadly said no, that I borrow a used engine from him while mine was getting repaired. We went to the flying field, I asked my friend to fly the plane first to make sure eveything was good with the new engine ( different weight , etc. ), this time the radio died, the plane went into a vertical dive full throttle, a total loss. The hobby store owner has aggreed to replace my plane, my question is....is this the norm that the equipment is not reliable, this is making me rethink, have I gotten involved in a hobbie that I will spend more time trying to make equipment work than having fun.