Interestingly, if my eyesight is good enough, the R prop looks feathered; if that was the dead one. It's been 1980 since my last PA-31 flight, but I remember it would not maintain level flight until the dead prop was feathered; then it flew OK. Calgary is 3500', so not excessively high. It was a good recovery and a controlled emergency landing. A 'well done'. I understand they were on approach to YYC. I doubt we'll find out, but it would be interesting to know why they could not make it on one engine. I know it's not a Perf A a/c, but in our annual flight tests SE flying with simulated feathered prop was possible. More current pilots will have some insight. I'm curious for nostalgic reasons.