Authorities in California were trying to determine Friday how a joyous university recruiting trip for low-income high schoolers turned into a fiery tragedy on a Northern California freeway.
A spokesman for the California Highway Patrol said it could take months to determine why a FedEx truck roared across Interstate 5's grassy median Thursday, slamming into a charter bus and sparking an inferno that left 10 people dead and dozens more injured.
The National Transportation Safety Board sent an investigative "go team" from Washington to the scene on Interstate 5 near the town of Orland, about 100 miles north of Sacramento. The CHP also was investigating.
The bus passengers were mostly high school seniors on their way to visit the campus of Humboldt State University in Arcata, Calif. Three chaperones, five students and the drivers of both vehicles were killed in the Thursday's crash.
NTSB Highway Safety Investigator Robert Accetta was leading a "multi-disciplinary" team sent to the site, the agency said.
CHP Lt. Scott Fredrick said investigators were breaking down possible causes for the crash, including whether the FedEx driver fell asleep, experienced mechanical failure or lost control because of a separate collision on the southbound side of the freeway.
Authorities also will probe roadway and weather conditions, Frederick said.
"Since these are such in-depth, detailed investigations, we don't expect to have a final report for a minimum of three months, 90 days," Fredrick said. "It could take as long as six months depending on what the investigation entails."
Many of the more than 40 students on board escaped through a window one of them had kicked open, running from the wreckage before the bus exploded behind them.
The Sacramento County coroner's office on Thursday confirmed the name of one -- Arthur Arzola, 26, of Rancho Cucamonga.
Humboldt State spokesman Frank Whitaker says Arthur Arzola was an admissions office staff member who was with the students on the bus when it crashed. He'd been the school's admission representative in southern California for the past year, focusing on recruiting low-income and first-generation students – the ones invited to the weekend "Preview Plus'' event on campus. He was a 2006 graduate of Don Lugo HS in Chico, Calif.
In his online bio, Arzola mentions that he liked to walk on the beach when he visited Humboldt. It was a major recruiting factor for him; Whitaker said that the campus's location usually ensured that students who visit it, attend it.
The investigation into the crash was focused on the FedEx truck. FedEx Freight Inc. has a satisfactory safety rating, according to Federal Motor Carrier Safety Administration records. FedEx Freight has a 0.7% unsafe driving on-road record -- one of the best scores for companies of their size that perform the same operations, according to FMCSA.
During the two-year period that ended Thursday, the company's vehicles were involved in 730 crashes in the USA. Twenty-three of those were fatal crashes, 223 were injury crashes and 484 were tow away crashes.
FMCSA's website simply lists a motor carrier's involvement in reportable crashes with no determination as to responsibility.
FedEx would not comment on any aspect of its safety record beyond a brief statement posted on its website. "All of us at FedEx are deeply saddened by the tragic highway accident in California. Our hearts go out to all of those involved and their families. We are cooperating fully with the officials investigating this accident."
The bus company involved in the crash, Silverado Stages of San Luis Obispo, also has a satisfactory safety rating. It was involved in one injury crash and one crash requiring a tow truck in the two years prior to Thursday, according to FMCSA.
Humboldt State issued a statement saying it was "deeply saddened, adding "Our hearts go out to those who have been affected, and we are here to support them, and their families, in any way possible."
Tommy Chang, the instructional superintendent for the Los Angeles School District, confirmed that students from Los Angeles schools were involved in the wreck, but he declined to provide further details.
The trip gave the students "an amazing opportunity to see what this amazing state has to offer in terms of higher education," Chang said.