United 777 Diverts to Dublin After Cockpit Windscreen Cracks Over the Atlantic

A United Airlines Boeing 777 bound for Milan landed in Dublin after a cockpit windscreen cracked at cruising altitude over the North Atlantic. The aircraft was carrying up to 276 passengers, according to a report by PaddleYourOwnKanoo.

The Flight

United flight UA19 left Newark Liberty International Airport at around 5:25 p.m. on Friday, October 9, on the roughly seven-hour overnight service to Milan Malpensa. The aircraft was a Boeing 777-200ER registered N782UA, a 29-year-old jet powered by Pratt & Whitney PW4000 engines.

As the flight approached Ireland, the aircraft began a rapid descent toward Dublin. One passenger described it as a “steep descent”, according to the report. The crew told passengers the flight was diverting to Dublin, but few on board knew why.

What Went Wrong

The reason became clear only after landing. The main windscreen on the first officer’s side had cracked while the aircraft was cruising at around 37,000 feet.

Reports so far do not say whether the crew declared an emergency, how low the aircraft descended, or whether anyone was injured. Nor do they describe how passengers were looked after in Dublin. At the time of publication, the aircraft was still on the ground there.

Why a Crack Is Taken Seriously

Cockpit windscreens on large airliners are built from several layers, so damage to one layer does not necessarily mean the whole window has failed. A complete failure that causes the cabin to lose pressure is described as extremely rare.

Even so, a cracked layer is not treated as routine. Crews generally want to get the aircraft on the ground as soon as it is safe to do so, and the decision to divert is made with that in mind. In this case, the flight was already close to a suitable airport, which made the choice simpler. The picture could have looked different had the damage occurred earlier in the crossing, when the nearest suitable runway would have been much farther away.

Past Windscreen Failures

Windscreen failures at altitude have happened before, and a few have been serious. In 1990, the captain of a British Airways BAC One-Eleven was pulled partway out of the cockpit when a windscreen that had recently been replaced came away at 17,300 feet, because it had been fitted with bolts of the wrong size. He survived after crew members held on to him while the first officer landed the aircraft.

Those cases involved a different failure from a cracked layer, and nothing in the reporting suggests anything similar happened on UA19. They do show why airlines treat any windscreen damage as a reason to land.

What We Do Not Yet Know

Several basic details remain unconfirmed. There is no information about how long the 777 will be out of service or how United have taken its passengers to Milan.