By Paul Kurtz

CHESTERFIELD, N.J. (CBS) — Investigators from the National Transportation Safety Board are already making progress in their probe of the deadly crash last week between a school bus and a truck loaded with debris that left one student dead and several others seriously injured (see related story).

NTSB spokesman Pete Kotowski says a team of nine investigators will have to determine the answers to a lot of questions — such as how fast the Mack truck was going.  The driver claims he was driving at the speed limit, 45 mph, when he saw the bus and slammed on the brakes, but ended up plowing into the other vehicle.

Kotowski also says the lines of sight near the accident scene will be a main point of focus of the probe.

“The line-of-sight evaluation determined that at some locations, the line of sight was obstructed due to environmental features of the intersection,” he told reporters today.  “The NTSB will be evaluating whether this reduced line of sight contributed in any way to the cause of the crash.”

Listen to the full NTSB briefing in this CBS Philly podcast (runs 36’21”)…

Download the full podcast

Another angle of the investigation is driver training.  The 66-year-old bus driver, who had received his certification just weeks earlier, has told investigators he never saw the truck before it hit the bus.  Kotowski says the driver had been driving the route for just nine days.

The NTSB will also look into human factors — medical issues, fatigue, distractions, and whether all students aboard the bus were using their seat belts.

The truck was carrying a load of asphalt and was five percent over its weight limit, according to investigators.

The entire probe is expected to take 12-16 months to complete, after which the NTSB will make recommendations if warranted to avert future accidents of this type.

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