When you’re flying a stable elevator, you can perform an inside “waterfall” (micro loop) by maintaining full up-elevator, and applying full power and a little right rudder to correct for increased propwash and P-factor. On the back side of the loop, quickly cut the power and neutralize the rudder. Then, at the instant the fuselage nears level at the bottom of the loop, simultaneously add a few clicks of power and a little right rudder to keep the fuselage level and correct for P-factor. You can then either descend in an elevator or increase the throttle and exit the maneuver. The plane will barrel roll out of this stunt if you fail to enter it with the wings level. Thus, only attempt an inside waterfall when the wings are level. With experience and altitude, you’ll be able to perform several inside waterfalls while dropping out of the sky in an elevator. Waterfalls can also be entered from slow flight or while hovering into the wind. The keys to this maneuver are getting settled into a stable elevator before attempting the waterfall and coordinating the correct amount of rudder with the throttle to maintain a constant heading.
Waterfalls can be enhanced with 60-degree elevator deflections and an aft CG. As a rule, however, it is a mistake to increase the elevator travel for the sake of one or two maneuvers if it ends up making everything else more difficult. This is a case where an advanced 3D pilot would use a more sophisticated radio that’s capable of a third flight mode with 60-degree elevator deflections for certain maneuvers.