A current senior curator told NBC News Tuesday that radio contacts caused air traffic controllers to lose radar and to have at least two radio contacts with aircraft pilots they directed into Newark Liberty International Airport last week.

Newark airspace controllers say at least eight to nine times in recent months, controllers have lost contact with pilots flying to one of the busiest airports in the United States.

"We lost all the radios! No backup!" said the controller. "Everything fell."

The Federal Aviation Administration did not immediately respond to a request for comment on Tuesday’s claim.

It was a week after directing controllers in and out of Newark’s Philadelphia Tracon area that lost all communication with the airport’s pilots on April 28, a near crisis under investigation.

Transport Secretary Sean Duffy said Monday that the connection between air traffic controllers and the plane was "30 seconds". He told Fox News that no plane was in danger of crashing.

Since then, the estimated number of no communications has climbed to 90 seconds.

"That was 90 seconds of a fully fulfilling plane sky," New York Senator Chuck Schumer said in Washington Tuesday. "Thank God nothing happened, but if it didn't change, we'd tempt fate. ”

The recording released by LiveATC.NET on Tuesday provides some insight into how air traffic controllers and pilots work in the crisis and avoid major tragedies outside one of the busiest air travel centers in the United States.

"I'm going to move you here because I've just been told this method loses all the radar," the air traffic controller can be heard telling the United Airlines 2243 pilot in one of the recordings. “Three of the four radar screens went black and they had no frequency.”

"Well, we're ready to move," the pilot replied, his voice calming.

The whistleblower said such back and forth could not convey the fear of the moment when air traffic controllers are currently trying to safely lead to the airport when the system is descent.

"It's like time staying still for a while," the controller said. "It's a terrible moment when we try to touch these planes and we can't achieve them."

The controller said the communication breakdown was not as long as 90 seconds, but "it was like 45 seconds to me" as they handled the crisis calmly.

"We went backing up the radio, and it didn't work, it didn't work," the controller said. "There was a fear of panic and fear that followed."

"These planes are flying with people and no one is talking to them - they are flying in the dark," the controller said. "It's like a silent cone. We can't hear them, but I'm sure they're calling us."

The aftereffect of what happened last week is still felt at Newark Airport on Tuesday.

For the ninth day in a row, travelers trying to fly out of Newark Airport had to compete with massive delays as the FAA tried to find a replacement for air traffic controllers during a 45-day trauma vacation.

On Tuesday, the call to Newark was delayed for more than four hours. United Airlines, the airport's main airline, canceled 35 round trips to Newark and offered changes to customers who wish to replace flights to Laguardia or Philadelphia Airport.

Although the FAA has not said how many controllers are on stressed medical disabilities, controllers who spoke with NBC News said the control tower is working to keep up with the flights as four experienced controllers and one trainee are now on leave.

A FAA spokesman said it would take time to replace them because any application or voluntary move to a certified controller in Philadelphia Tracon and directing the aircraft to Newark airspace will have to be conducted with additional training at the FAA’s Air Traffic Control Training Center in Oklahoma. After that, they will be asked to conduct on-the-job training in Philadelphia.

It would take about a year and a half to prove an air traffic controller in any facility, a spokesman said.

The FAA moved the controller in charge of the aircraft, which departed from Newark to Philadelphia last year from Newark. The move is designed to reduce the workload of controllers in the facility, which are also handling traffic for major New York City airports.

Co-CEO Scott Kirby said Monday that Faradelphia Tracon in Philadelphia has been “having been understaffing for many years”.

"Newark Airport cannot handle the number of aircraft planned to operate there in the coming weeks and months," Kirby said.

Duffy said the shortage of air traffic controllers is an ongoing national problem. He said there are 3,000 vacancies nationwide and he plans to develop a strategy to provide incentives to the workforce.

"Inadequate investment in maintaining critical air traffic control infrastructure, delaying upgrading to modern 21st century air traffic control technology, and under-air air traffic control staff have led to fragile systems nationwide," New Jersey Gov. Phil Phil Murphy added Monday.

"Our outdated air traffic control system is affecting our workforce" and is working to improve the reliability of communications in the New York City area," the FAA said in a statement Monday.

But for safety, the FAA must slow down reaching Newark until they find enough air traffic controllers to handle the workload.

"We will keep the public up-to-date as we address these issues. The FAA will continue to be transparent with the public about the status of Newark and each airport," it said.