Rotary backrest recline mechanism

A passenger seat assembly comprising:

• a frame member;
• a backrest;
• and
• a backrest recline mechanism, including:
• a first shaft attached to the frame member, the first shaft having a slotted ring defining capture slots and an interior annular space;
• a control ring having a first end disposed in the annular space;
• a second shaft attached to the backrest, the second shaft engaged with a second end of the control ring;
• a first collar rotatably disposed around the slotted ring, the first collar having a plurality of release recesses;
• and
• a plurality of first bearings respectively retained within the capture slots beneath the first collar,
• wherein:
• in a first rotational position of the first collar, the plurality of release recesses align with the capture slots to rotationally disengage the frame member and backrest;
• and
• in a second rotational position of the first collar, the plurality of release recesses misalign with the capture slots to rotationally engage the frame member and backrest.