Regarding compatibility of either Defiant or V-280 with existing US Army facilities, taking a look at Unified Facilities Criteria UFC 3-260-01, both aircraft would require a similar parking pad layout along the lines of the current Navy/Marines V-22 Parking pad in dimensions as shown below:
As far as Hangar Facilities go, here’s a table and figure out of UFC 4-211-01 that talks about clearances etc. I can tell you right now that my facility would only accommodate 2 V-280s per hangar and maybe 4 Defiant vs the 6 H-60’s we can currently accommodate:
I looks like we would lose 2-3 parking pads per aircraft depending on which aircraft was selected.
FltMech