Several equipment outages over the past two weeks at the Philadelphia-based air traffic control center that guides planes to and from Newark Liberty International Airport have raised concerns on how safe it is to fly at one of the nation’s busiest airports.

United Airlines executives are trying to reassure their customers it is safe to fly at Newark Liberty International Airport​, despite all the recent problems.

United Airlines Chief Executive Scott Kirby told customers in an email Monday that it is “absolutely safe” to fly in and out of Newark Liberty International Airport following two weeks of technology and air-traffic control staffing issues that have plagued the New Jersey transit hub.