Dan wrote:

Interesting layout. I assume the rotors would be used in
autorotation during horizontal flight. If this were done full time it
wouldn't be able to take off vertically, but would make one big autogyro.

That was the idea, if forward flight lift would shared between the
windmilling rotors and the wings but the prototype crashed, and they
gave up on it.
We tried the same concept in a lot smaller form on the McDonnell XV-1:
https://www.nasm.si.edu/research/aer...donnel_xv1.htm
The one I keep trying to find a photo of on the web is the Yak VVP-6
design for a huge helicopter using six rotors (three mounted one behind
the other on three stub wings on each side of the fuselage), and carried
a six missile SA-2 battery on its back along with the associated radars,
and more reload missiles inside its fuselage. This monster was to be
powered by no less than a total of 24 turboshaft engines, pylon mounted
in two dual pods on each of its six stub wings.
The giant helicopter was designed to work in conjunction with S/VTOL
fighters and attack aircraft by letting a mobile missile site to be
deployed to front line positions quickly.
After the work on the Yak S/VTOL aircraft ceased, it was canceled before
any prototype had been built.

Pat