A barrel roll is not that easy to pull off for a novice at aerobatics. An aileron roll (which is NOT 1g) is easy - EXCEPT that in many aeroplanes the nose will drop 60+ degrees during the roll - I never new that until I did a bit of aero's, which is why you may have to pull 30 degrees up before you roll ("put your feet on the horizon").
A barrel roll on the other hand requires much more skill and coordination in pitch and roll which is why it can easily be f**ked up by a novice (like me
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