V-22 Osprey Project - Transition Flights and Crash

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I took the Osprey out to my club field to start testing the transition into forward flight. It certainly got the attention of my fellow club members who were on site! The first two flights went off without a hitch. I was able to successfully transition the rotors to 45 degrees. I need to tune some additional parameters as the controls became very mushy and non-responsive. I think the rotor controls were phasing out before it had enough airspeed to make the flying surfaces functional. On my third flight disaster struck! I had been flying around just fine, but as I transitioned back to hover for landing it suddenly lost control and started pirouetting to the ground. I hit the throttle hold at tree level and it impacted the ground belly first.

At the scene of the crash, I could see that the aluminum tube supporting the right rotor had pulled out of the wing enough for the rotor to flip 180 degrees to the left. I suspect that was the cause of the crash. The left wing broke the carbon spar at the root upon impact. The 3D-printed rotor plates broke, but those are designed to be sacrificial. The rotor mechanics seem to be ok. The shafts look straight, no gear teeth missing, and the servos seem fine. The rotor blades didn't even break. When I got home, I opened up each wing and sure enough, the rib in the left wing that retained the aluminum tube had broken and allowed the tube to pull loose. The right wing that broke the spar had actually pulled the spar tube loose from the ribs as well when it broke. Both wings will need a complete rebuild. I've already fired up Fusion 360 to examine how I can reinforce some areas of the wing, shave weight in other areas, and address some issues that made assembly difficult.


The foamboard body suffered only minor damage when it pancaked into the ground, so that is a relief. By the time I get new wings built, the tri-blade heads should arrive from China. I'm looking forward to seeing it with those attached! I'm sad it crashed, but I figured it was inevitable in the process. The real V-22 was almost scrapped due to how many crashes it had. Surely my version would follow a similar path.



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