Below is an artists impression of the Bell D190B, a tilt-duct VTOL derived in part from the X-22. The D190 series, dating from the early 1960’s, was for a more-or-less common airframe design that could carry out a number of missions. Interestingly, variants of this design were considered for “parasite” roles. The aircraft could hard-dock to the underside of a C-130; the larger transport aircraft could then haul the smaller VTOL around the world, where it could serve as a rescue plane (note the rectangular hatch on the top of the fuselage). Another idea was for the small VTOL to serve as a crew or passenger transfer system for EC-135J (707 derivatives) flying command posts, including transporting VIPs (read: politicians) away from nuclear strikes to orbiting escape planes.
Sadly, while I’ve found many bits and pieces on this over the years, I’ve yet to come across good design data. If anyone has anything, I’d love to see it.
I have made the full-rez version of this scan available at the APR Patreon for $4-and-up patrons. It is in the APR Patreon “Extras” Dropbox, in the 2015-04 folder.