Rig that hit Asiana crash victim didn't have heat sensor installed

July 22--San Francisco airport officials had purchased heat sensing equipment that experts say might have prevented a 16-year-old Asiana Airlines victim from being hit by a fire rig, but the infrared technology to detect and map obstacles was not acquired for the rig that ran over the girl.

Ye Meng Yuan, a student from China, was covered with fire retardant foam when she was hit by at least one of the airport's rigs shortly after the plane crashed on landing on July 6. On Friday, the San Mateo county coroner said Ye was alive when she was hit by the rig.

The two-axle truck is believed to have run her over as it moved to get a better position to spray foam on the fire, police investigators have said. The older-model engine -- No. 37 -- did not have infrared forward-looking imaging technology now required by federal law, fire officials acknowledge. Other airport rigs are equipped with the technology.

The system measures heat given off from objects on the ground as well as hot spots left in burning debris. The equipment is designed to detect objects that are otherwise invisible in fog, smoke and debris. It is especially vital on giant airport rigs, which are difficult to see around because of their size.

In 2009, the Federal Aviation Administration urged -- but did not require -- that U.S. aircraft rescue firefighting rigs be equipped with the infrared cameras. Such sensing technology has long been available. In 2011, the FAA required all new rigs to have forward-looking infrared sensing equipment to alert drivers to obstacles.

San Francisco Fire Chief Joanne Hayes-White confirmed Sunday that some rigs at the airport did not have the equipment fully installed. She did not know if the equipment on hand -- which she believes was purchased before 2011 -- could have played a role in possibly preventing Ye's death.

"I don't know one way or the other. I don't know enough about the technology," she said.

Hayes-White said the rigs in the airport's arsenal were purchased before the FAA requirements were in place.

The system the airport ordered from a Canadian maker allows the driver to see a real-time map of upcoming obstacles created with an infrared thermal imager.

Hayes-White said the airport has always been cooperative in procuring new equipment.

"We tell them what we like, what we need and what is required. They are very good about paying for it," she said.

Assistant Deputy Fire Chief Dale Carnes said Sunday that the department is in the process of installing the Driver's Enhanced Vision System on three of its other airport rescue firefighting rigs.

He said multiple agencies are involved in the installation process and he did not know when it would be completed.

"It's basically designed for inclement weather, to navigate safely."

Carnes said he did not know whether the system would have been able to prevent Ye's death. "That would be complete conjecture," he said.

But a veteran FAA airport safety expert turned consultant said the system is designed to do just that -- avoid hitting people.

"Had the person been alive -- the foam has a cooling action, but the body would still have given off some ambient heat that could have been visible," said Ben Castellano, who was acting manager of airport safety when he left the agency in 2009 after 34 years.

As for detecting humans, Castellano said: "That was the main purpose of the development" of the technology.

In this situation, he said, the conditions that could have made the technology useful "lined up together."

Jaxon Van Derbeken is a San Francisco Chronicle staff writer. E-mail: [email protected]

Copyright 2013 - San Francisco Chronicle