Two more equipment failures plagued Newark Liberty International airport over the weekend, triggering a series of disruptions and delays starting at the airport and extending over many US and international routes.

On April 28, a 90 second radio and radar failure at Philadelphia Terminal Radar Approach Control (TRACON) where air traffic controllers control Newark airspace. This caused confusion, prompting hundreds of delayed, diverted and canceled flights.

A repeat failure occurred Friday when a telecommunications outage once again brought down the radar and communications Newark controllers. The outage occurred around 3:55 a.m. and lasted approximately 90 seconds,” a Federal Aviation Administration (FAA) spokesperson said.

Another equipment failure occurred Sunday morning. A ground stop was issued by the FAA, stopping all aircraft destined for Newark from departing their origin airports. Aircraft in and out of Newark were slowed to a level that could be then handled by the on site control tower and controllers from New York Air Route Traffic Control Center (ARTCC) which overlies the TRACON airspace but normally does not have to work that airspace. The ground stop lasted for about 45 minutes.

“The FAA briefly slowed aircraft in and out of the airport while we ensured redundancies were working as designed,” the FAA said in a statement. “Operations have returned to normal.”

A recording from LiveATC.net showed the moment the radar went down on Friday. Radio communications also went down but quickly returned, allowing controllers to issue quick instructions to pilots under their control.

“FedEx 1989, I'm going to hand you off here. Our scopes just went black again,” one controller radioed to a pilot. “If you care about this, contact your airline and try to get some pressure for them to fix this stuff.”

“Sorry to hear about that,” the FedEx pilot responded.

In another controller/pilot exchange, the controller told the pilot about the outage and instructed the pilot to maintain distance from the airspace if the pilot could not reach the controller.

One controller said that the outage began when all of the virtual buttons lit up on the Enhanced Terminal Voice Switch (ETVS), which allows controllers to quickly dial other controllers or switch frequencies.

“I would say the scopes that went black were gone between one and two minutes. They returned at different times. The frequency cut out for only a few seconds,” the controller reported.

Technical Operations, or Tech Ops, checked the radar scopes later in the morning and certified that “everything was A-OK,” said the controller.

FAA officials blamed the Friday incident on the loss of a vulnerable data line that connects a radar facility in New York to Philadelphia TRACON. Controllers responsible for Newark airspace used to work from that New York facility, but were transferred to Philadelphia last year in an unpopular attempt by the FAA to ease staffing concerns.

In the style of military personnel, controllers and their families were uprooted from their New York homes and moved to a place they did not want to be, with little to no input. Presumably, the radar and communications data also had to be routed to the new facility.

Reports of equipment failures had occurred even before the April 28 blackout and were attributed to the ill-advised move, but clearly were not taken seriously by the FAA.

The FAA announced last week before the two outages that it will install backup data lines connecting the New York facility with Philadelphia TRACON and add three new high bandwidth fiber optic telecommunications lines between the two facilities, but such work could take months, if not years.

In an interview aired on CBS' Face the Nation over the weekend, United Airlines CEO Scott Kirby claimed it is still safe to fly in and out of Newark, which is one of United's major hubs.

“It absolutely is safe at Newark and in the entire country. And the reason is when these kind of outages happen, we train for them. We have backup procedures, we have backups to backups to backups to keep the skies safe, which is always the number one priority in situations like this,” Kirby said.

“When the radar outage happened at Newark, what happens is the pilots look for alternative frequencies. They go to alternative centers with alternative radars and they also have a system in the airplane where, where they can see its equivalent of radar. They can see their position in the sky and all the other aircraft around them. But what we do is slow the whole system down, which is disruptive to customers, but it's entirely safe.”

While what Kirby said is technically true, what we are witnessing in real time is the removal of these layers of “backups to backups” in the US National Airspace System (NAS). Air traffic controllers are routinely briefed on the “swiss cheese model” of error reduction, which states that the more layers of imperfect safety and redundancy there are, the less chance a fatal mistake or failure can make it through the holes in the safety system.

Airliners do indeed have their own radar and safety equipment, but they are not perfect and pilots do not see the big picture of the air traffic environment. This equipment has had its own fatal failures in the past and should never be relied upon by itself unless an emergency situation like that at Newark presents itself.

In the aftermath of events like this, the FAA consistently claims that “safety was never compromised.” This is double-speak for “nothing happened this time.” The level of safety confidence was definitely eroded during these incidents.

On Thursday, Duffy announced a plan to modernize and overhaul the NAS. This proposal will require Congressional approval and cost billions of dollars, and it will take years if not decades to implement. It is impossible to quickly and entirely replace the complicated safety system protecting some of the world's most complex airspace.

The FAA is trying to use the stick for controller retention instead of the carrot, as they are attempting to increase the mandatory retirement age in place for safety reasons in order to force controllers to stay well beyond the years their abilities will remain sharp. Bonuses were offered to controllers about to retire as well as new hires, leaving out the bulk of controllers in the middle of their careers to languish in terrible conditions with poor pay.

The only way to fix these issues is for controllers to wage a struggle for better pay and benefits, to reverse the FAA's decision to move Newark controllers, and for a massive wave of hiring and training.