Orcas aren't naturally aggressive toward humans. In fact, A C Clarke hypothesised using them as oceanic 'sheep dogs' to herd other marine life in the future.
Back in the late 70's, I helped rescue a dolphin on Rhos beach. after an hour of getting it to the waters edge, we managed to get a lift into deeper water from a passing speedboat, I got in the water with the dolphin to make sure it was going to swim under its own power. and it eventually moved away, and disappeared for a short time, then I spotted a fin in the water coming towards me very slowly.........it took a lot to stay in the water and convince myself that it was the dolphin
my excuse for being wary it was not to long after the film Jaws had been released.
Sorry, but I would need to be hypothesised to have not headed for the beach.