Well done dook. The Kawanishi H11K Soku (Blue Sky)
Japanese Aircraft of WWII - Kawanishi H11K Soku (Blue Sky)
It didn't get beyond the wooden mockup stage before it was destroyed in a bombing raid in April 1945. It was a very large aircraft - 100,000 lb AUW. The wingspan was 157', 44' bigger than the Sunderland and 43' less than the Mars.
I'm surprised it had only three machine guns.