The UAVFrame multirotor frames have got to be the nicest frames I have seen yet. Here are some videos, one with their hexacopter looping with a takeoff weight of 5.32 Kg including a attached crate and crashing. Another with the crash results. One shows they can loop with the crate and the last shows it lifting off with a combined weight of 10.14 Kg. Looping with a crate: Crash results: Successful loop with crate: Here is the same hexacopter flying with the beer crate fill of bottles. Takeoff weight 10.14 Kg:
LOL. I think the beer was the inspiration. "Hoi Jurgen, was machen wir mit diesem flug ding? Ich weiss was Peter, wir hangen dieses bier schaktel von dem ding und loopen es". OK, it's not Dutch it's Deutsch, but you had the idea anyway.