I'm creating a V-22 Osprey replica with the new robotic parts (incredibly original idea, I know). I am using the largest helicopter blades and the R7000 turboshaft engine. The vehicle lifts off fine, albeit with some help from vernor engines, but the second I enter it into "plane" mode the engines are massively too weak to propel it, capping at about 35m/s. The vehicle weighs 66,5 tonnes. Is there any way of improving the thrust/weight ratio without adding more rotor/jet engines? Why is it that they have enough power to lift the whole thing off the ground, but not to propel it?
Since I'm new here and couldn't figure out how to insert images into my post, here's an imgur link: https://imgur.com/a/msRQ73z