Hey Nelson, welcome to the discussion group, man! I am no expert in power aerobatics, however, a barrell roll is essentially a loop done wit a bit of aileron in. So if you can do a loop with 1G once you're at the top, then you can also do a barrel roll (which again is not a roll). Think of doing a quite narrow loop when instead of releasing to zero gravity at the top, you keep in a 1G. See you around!
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