1931 Lanier XL-4 Vacuplane - photos

[Frank S]

And down the rabbit hole I went until I happened across this.
http://eaach1.org/Design/Comm4v1_FullR4.pdf
A long and very informative read

[mr herb]

Any idea where all the air that was sucked through the slats exited? Where did the suction come from? The prop blades (assuming normal rotation) will pull the aircraft, and create positive pressure.

It has some university logo on the side, so it would seem some intelligence was wasted (and also $$ )