Air traffic controllers at the Newark International Airport on Friday briefly lost their radar system, the second time in recent days such an outage has occurred there. 

The first incident occurred April 28, resulting in hundreds of flights being delayed or canceled at the New Jersey airport.

In response to Friday's outage, the Federal Aviation Administration said the radar system, which tracks planes, went dark at 3:55 a.m. for about 90 seconds.

The busy airport has struggled for about a week now with delays and cancellations, the result in large part by a shortage of air traffic controllers and the outdated equipment they use. 

Transportation Secretary Sean Duffy on Thursday announced a multi-billion-dollar plan to replace the country's aging air traffic control system, according to The Associated Press.