Originally Posted by Brian Carlton

Without engines, the CG of the aircraft moves aft to a significant degree and, apparently, is just slightly forward of the main gear.

It wouldn't take much lift to bring the nose off the ground as was evidenced in the video.

Whether the wings would generate any lift at 70 kts. is the real question.

Typically, such an aircraft would never generate any lift until it rotates and it needs 120 kts. for sufficient downforce on the tail to effect rotation.

So, I'm a bit skeptical of the result.