Just to add that a TCAS manouver should not be a violent one but a smooth pitch up or down at no more than 1.5g if in fact the RA even suggests anything other than not changing your vertical speed which could even be zero. A normal TCAS RA manouvre would probably not be felt or noticed by anyone on the a/c outside of the flight deck.
If a flight attendant was injured in the TCAS incident described in the article above, the crew probably had to use a much more violent manouver than was indicated by TCAS.
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