Ferdinand aka. EndOfDays did it again!
His latest project is an X8 with 8x T-Motor U8 with 29" propellers.
To test the motors' performance and efficiency, he fixed up an X4 quad frame from aluminum. His first test was already impressive: 4kg frame, 4kg batteries (8S) and 4kg payload = 12kg TOW - overall flight time: 44 minutes.
Follow his progress on RC Groups: http://www.rcgroups.com/forums/showthread.php?t=1994599