LaGuardia crash reveals deadly gaps in airport radio and tracking systems

A worker in the Port Authority truck that sparked last month's deadly crash with an Air Canada plane at LaGuardia Airport told investigators he heard a controller repeatedly call out "stop" before the collision.

But due to a flurry of communication meltdowns, he didn't know the order was directed at his vehicle, according to a report released Thursday by the National Transportation Safety Board.

The report lays out how seven different emergency vehicles were operating on the airport's runways around 11:30 p.m. on March 22 to respond to a plane that reported smoke in its cabin. It stated that none of the vehicles had transponders typically used to precisely monitor the locations of vehicles at airports, and "simultaneous radio transmission on the same frequency obscured" all the drivers' communication.

The NTSB said the truck was caught in that chaos as an Air Canada jet was descending into LaGuardia.

Due to the communication problems, the airport's systems weren't able to "predict a potential conflict with the landing airplane," according to the report.