Newark's Liberty International Airport has been hit hard by delays and technical issues over the last few weeks, and a major transatlantic flight headed for the airport was recently canceled. The flight,

Amid dire conditions at the airport, an airline operations crew has had to figure out how to get more than 600 flights a day to take off and land without incident.

Newark Liberty International Airport is one of the largest hubs of United Airlines, and the congested airport is also the Chicago-based carrier's biggest operational challenge. The company told 1.5 million customers in a note on Thursday that congestion at Newark has eased since it reduced flights there.