The cockpit window of a United Airlines 737 suddenly opened as the aircraft was climbing out of Windsor Locks. Read on to find out more about this incident.

Background

United Airlines 1274, the flight involved in this incident, is a regularly-scheduled flight between Windsor Locks-Bradley International Airport (BDL) and Washington-Dulles International Airport (IAD). 

Flight 1274 is currently the only United-affiliated flight on this route operated by a mainline aircraft, while the other four daily flights between these airports are operated by ERJ-145 and E175 regional jets.

Flight 1274 is primarily operated by a Boeing 737-900ER, although occasionally, it gets swapped to a 737 MAX 9. This flight has a scheduled departure time of 6:00 a.m. EST. The aircraft operating the flight remains overnight in BDL after arriving from Dulles around 11:36 p.m. EST.

Flights between BDL and IAD are just shy of an hour long. As mentioned earlier, this route is currently operated five times per day on mostly regional jets. Why is a 737 operating this route? The reason is quite interesting. 

United's hub at Washington-Dulles has two huge departure and arrival banks of flights between 8:00-10:00 a.m. and 8:00-10:45 p.m. approximately. As such, there are usually a high number of passengers onboard the 6:00 a.m. flight out of BDL and 11:36 p.m. into BDL who are connecting in Washington. 

Such a high number is not present on the other four daily flights between these airports, thus not warranting a mainline jet to operate them. This trend holds true for all three U.S. legacy airlines that serve small- to medium-sized airports on certain route pairings. They operate mainline planes on the last flight of the day in and the first flight of the day out of a specific airport because these flights are timed in conjunction with busy bank periods. 

As such, most passengers on those specific flights will connect through the airline hubs to flights elsewhere, thus warranting the need for a bigger jet.

The Incident

On April 18th, 2023, United 1274 was climbing out of BDL when one of the 737's cockpit windows suddenly opened, causing lots of wind to get into the cockpit. As captured on the ATC audio recording, the crew declared an emergency with lots of wind noise in the background. The flight turned around and landed safely back on RWY 24 at BDL, where it had departed from some minutes earlier.

The aircraft involved was N66825, an eight-year-old Boeing 737-900ER delivered to United in May 2014. After landing safely back at BDL, the aircraft spent most of the day receiving repairs. It was later ferried to Chicago O'Hare that evening, from where it resumed regular duties flying to Los Angeles.