jh_MacLeod
Contributor
Being overweighted can help lead to panic in the if anything goes wrong but did your contact say how the two drowned? Did they just sit on the bottom until their air ran out? That doesn't sound likely. Did it happen when the student ran out of air and had a death grip on the instructor, pulling the reg out of his mouth? Possible but just being over weighted in itself won't drown them. Great point though that panic kills.
I confirmed that they were both found unresponsive on the surface, so my assumption that they were overweighted was unwarranted. I was also told that they had not refilled their tanks from the previous dives and that they all started the dive with around 50 bar. The student's bcd hose was separated from the bladder, so perhaps that caused the buoyancy failure. The student's tank was empty also, but I haven't heard definitively which failure came first. So, it appears that the drownings occurred very near the surface.