Unfortunately, I don’t think TCAS would have helped in this case since it’s inhibited below 900 AGL. They still would have had TA only though and on live ATC it appears the helicopter was instructed to pass visually behind AA. I guess we’ll have to wait for the final report to really know what happe...

I heard it’s 8 E175, 6 RJ and 6Q. Bases were YYZ and YUL, unsure of the exact breakdown for each base.