SeaWorld Trainer's Final Moments

Could the tragic death of a trainer at SeaWorld have been prevented?  Videos of those final moments before the killer whale attacked its trainer are being reviewed and they reveal some critical and perhaps fatal errors. INSIDE EDITION reports.

Did SeaWorld trainer Dawn Brancheau make a fatal mistake while interacting with Tilli the killer whale? That's the question swirling in the wake of a video shot by a tourist at SeaWorld in Orlando.

The footage shows Dawn with Tilli just minutes before the attack that cost her her life. At one point, Dawn shakes her head back and forth. Tilli does the same. You can see Dawn's ponytail swaying to and fro. Dawn can also be seen lying in the water with Tilli, apparently on a shallow ledge called a slideout.

Authorities say Tilli then grabbed her ponytail and dragged Dawn into the pool, drowning her and causing numerous traumatic injuries.

"He probably just saw it as a novelty, grabbed her by the hair and pulled her in, probably not in an aggressive manner," said Thad Lacinak, the former head trainer at SeaWorld Orlando.

He knew Dawn well, and trained her. He praised her skills with animals but he thinks she made an error of judgment that day.

"Allowing her ponytail to drift into the water where the whale grabbed it, that would be a mistake and I'm sure Dawn, if she was sitting right here next to me, would say the same thing," said Lacinak.

SeaWorld officials insist no staffers were ever allowed in the water with Tilli because of his dangerous temperament. He has now been involved in the deaths of three humans.

INSIDE EDITION's Les Trent showed SeaWorld spokesperson Julie Scardina the video of Dawn on the slideout.

"People looking at the picture who realize that this whale has already killed two people, would say it's probably not a good idea, probably not the best protocol, to allow a trainer to get that close," said Trent.

"And that is definitely what is going to be reviewed now," said Scardina.

At 12,000 pounds, Tilli is twice the size of the next biggest killer whale at SeaWorld. Tilli is said to be worth $2 million, and has sired 12 calves and is described as "big and randy."

Trent asked Scardina, "What do you say to those critics who say that these whales are just really unsuited for captivity because they're so large."

"Well, I actually say that first of all, we have state-of-the-art facilities for them. We care for them just like all of our other animals. So, no matter the size, we still have the experience and the expertise to be able to do it like nobody else can," said Scardina.

Dawn's family issued a statement Friday saying, "Those who knew and loved her have suffered a tremendous loss, one so unexpected that it is extremely difficult to even process."