SAS
Once again.....what could possibly be used as evidence here???
How does anyone "prove a claim"??? How does anyone "substantiate a claim"?
What is it you want to see posted? Give an example of what could be considered proof of anything. This doesnt cut it I assume.
Compared to both helicopters and conventional turboprops, the Osprey has a lower acoustic signature due to the tiltrotor's reduced rotor rotational speed. It also uses very low thrust for cruise propulsion. The V-22 flying in aircraft mode produces a distinctive sound, described by observers as a "throaty and muted hum - more like a vehicle than a helicopter." The observers noted that, in combined operations, the steady buzz of the MV-22 was frequently masked until the last minute by the "whop-whop noise" of AH-1 Cobras and UH-1 Hueys that were supporting nearby. Overall, as compared to the CH-46, the MV-22 is less noisy while in the aircraft mode, and provides comparable acoustic acquisition cues while operating in the helicopter mode.
Regarding the ISS, to me, its a system of shafts and your claim of a singular "shaft" being necessary is flawed.
Under normal, two engine operations, each engine delivers its power to its corresponding proprotor through the PRGB. Only a small amount of power (511 hp max) is transferred down the pylon mounted drive shaft, through the TAGB and down the interconnecting drive shaft to the MWGB. The MWGB contains the auxiliary power unit (APU), the constant frequency generator and the variable frequency generator. The MWGB transmits power between the left and right interconnecting drive shafts without changing speed or direction of rotation.
During single engine operation, power is distributed from the remaining engine to both proprotors through the interconnecting drive shaft. This diagram shows this condition with the right engine failed.
So basically outside of OEI conditions, there are a pair of shafts feeding the MWGB. If one is lost, APU and generators should still be fed by the other. If both shafts were lost, you would lose the generators, and I would assume there are other backups to keep the system airworthy (DC bus battery?).
Do you interpret this differently?