RE: Twinman's Nightmare Fly's !
Five engine B-17? Yep there was such a critter. I was assigned to Air Force Flight Test Center at Edwards AFB 1955 -1959 and a B-17 was used to flight test various engines including Turbo-Props for Allison and GE. One installation the prop was so big it just cleared the ground when acft was level. You might be able to Google and find more info.