Blade departure path; hydraulics
[QUOTE=pilotmike;10123195]The only force that kept the blade continuing its circular path around the shaft was the 'inward' centripetal acceleration force while it was still attached.
Once the blade has failed at the root, that centripetal force has gone, there is no further acceleration force acting on the blade, and its trajectory immediately becomes linear, directly tangential at the moment of release.
Yes, but:
1. We need to be clear this is happening in airframe co-ordinates.
2. At the moment of blade departure, there will be a significant pressure drop (as before, when the blade was attached) from the back to the front of the blade. Thus, I'd expect the blade's departure path to somewhat behind tangential, opposite the direction of rotation and somewhat towards the nose. That's likely how the blade got around the cowl leading edge to smash the window.
On a different topic, I see reports of a hydraulic failure but evidence of that in the ATC recording. Surely the crew would have reported that to ATC if it did happen?
Well done, crew!