Pilots in Houston collision acknowledged instructions to wait but took off anyways, NTSB says

The pilots of a small jet that collided with another plane last month in Houston barreled down a runway without permission, oblivious to urgent orders to stop while troubleshooting cockpit alerts, according to a preliminary report.

The National Transportation Safety Board said the Hawker pilots acknowledged instructions to line up and wait for clearance to take off from Houston’s William P. Hobby Airport on October 24. Instead, the jet accelerated to take off, ultimately colliding with a Cessna Citation Mustang that was landing on an intersecting runway. They later told investigators they thought they had been cleared to take off.

“November nine alpha alpha, stop, hold your position,” a controller ordered the pilots who were taking off without permission, according to the report. “Alpha, alpha, hold your position, stop.”

The NTSB said the departing pilots did not respond to either order and didn’t notice the incoming plane “until about 1 second prior to impact and described the feeling of the impact as a ‘thud.’ ”

The pilots of the Citation – which experienced substantial damage – told investigators they did not even see the other plane and described hearing the sound of a truck tire blowing.

The report says that while taking off, the Hawker pilots were addressing unrelated cockpit warnings. That plane was equipped with a cockpit voice recorder that the NTSB will analyze.

The incident interrupted flights at the Hobby airport while workers cleared the crash debris. No one was hurt in the incident.

The collision involving two smaller jets followed a series of close calls involving airliners at US runways that brought attention to runway incursions. A Senate panel is set to hold a hearing on the incursion issue on Thursday.

CNN’s Pete Muntean contributed to this report.

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