When I watched the launch of HYLAS-4 and Superbird-B3 on Ariane 5 ECA, for a moment it seemed that ESA is also experimenting with fairing recovery - with a fairing which flaps its wings and flies like a beautiful white swan to its destination. It can be seen in this video at 3:25 after the launch (link should start the video just before the event).
ULA's fairing seems to be doing the same.
The only other fairing I am familiar with is the one used by SpaceX. The fairing is mainly composed of aluminum honeycomb structure covered by what I suspect is carbon fiber or fiberglass. I would expect this structure to be rather stiffer than what was on the Arianespace video.
Are all payload fairings similar in their mechanical properties?
Is it the fairing separation mechanism that causes the Arianespace fairing to flex so much?