Why do killer whales turn on there trainers?

There is no evidence to suggest that killer whales turn on their trainers. Orcas, in general, are highly intelligent and possess strong social bonds within their pods. There have been instances of orcas attacking humans in the wild, but these cases are rare and often involve situations where the orcas are defending their young or territory. In the case of orcas in captivity, they are carefully monitored and trained under the supervision of experienced professionals to ensure the safety of both the animals and the trainers.