After at least six incidents this year, the nation’s top aviation official says he does not know whether close calls involving airliners are on the rise, but says the issue and its causes will be examined at a safety conference next week.

“It’s a good question,” Billy Nolen, acting head of the Federal Aviation Administration, said after testifying to the Senate Commerce Committee – his second time there in a month.

Nolen defended his agency’s handling of the safety incidents, some of which were averted when pilots – not the air traffic controllers from his agency – avoided a collision. He said officials are “treating each of these as if it had been an actual event.”

“The FAA absolutely has a grasp on the situation and it’s something that we look at every day,” Nolen told reporters. “We’ll take a look at these near misses and see if there are lessons to be learned.”

He said a major safety meeting next week will include industry officials and ask the “hard questions.”

“Let’s just stop to see – are there any dots that we need to connect, and if so what might they be?” Nolen said.

Inside the committee room, Nolen said that the agency does not take safety for granted and is looking for opportunities to improve.

The FAA pointed to its Runway Safety Council (RSC) and Runway Safety Action Teams (RSAT) that are aimed at mitigating or eliminating such incidents.

Nolen also said that the FAA will use “every step, every tool that we have available in our disposal” to address unruly passengers like one accused of trying to stab a flight attendant earlier this week.

Last year, the agency logged more than 2,300 reports of unruly passenger behavior. Investigations were initiated in 823 cases, and 80 cases were referred to the FBI for criminal review.