Boeing 777 Engine Explosion Results in Grounding of Some Airplanes That May Carry Similar Risks

Following a mid-air engine explosion on United Airlines flight this weekend, Boeing is suspending flights for nearly 130 of its 777-model passenger airplanes.

On Saturday, a Boeing 777 engine explosion occurred on United Flight 328, on its way to Honolulu, dropping engine debris around Broomfield, Colorado, before the plane was able to land safely. While passenger, crew and area residents had a serious scare, remarkably no injuries were reported in the incident.

In response to the near disaster, Boeing issued a statement on February 21, recommending all 777s equipped with Pratt & Whitney 4000-112 engines be grounded while the National Transportation Safety Bureau (NTSB) investigates the incident. The affected airplanes include 69 in service, and 59 currently in storage, according to the aerospace company.

Both United Airlines and Japan had already grounded the airliners, and the Federal Aviation Administration (FAA) announced it was also grounding all of the aircraft used in the U.S. on the same day as Boeing’s announcement, at least until a proper inspection is completed. The United Kingdom has barred the affected 777s from flying in its airspace.

The NTSB issued an investigative update that same day, indicating it is recovering parts from the plane which plummeted to the ground after the incident. The bureau reports United Flight 328 was on its way to Honolulu from Denver, carrying 229 passengers and 10 crew when the incident occurred.

“The initial examination of the airplane indicated most of the damage was confined in the number 2 engine; the airplane sustained minor damage,” the NTSB reports. “The examination and documentation of the airplane is ongoing.”

The preliminary investigation found that the inlet and cowling had separated from the engine, and that two fan blades were fractured. One fractured near the root, and the other was fractured about mid-span. The remaining fan blades suffered damage to the tips and leading edges, and part of one of the fan blades was found imbedded in the containment ring of the engine.

The incident occurred just days after Boeing agreed to pay $2.5 billion to settle a lawsuit by the Department of Justice over problems with its 737 Max airliners, which were grounded in March 2019 following two fatal accidents which killed 346 passengers and crew members combined. The company has also settled a number of wrongful death lawsuits filed by family members of those who died in the two accidents.

Both crashes were initially attributed to the aircrafts’ angle of attack system, which is the attitude of the wings in relation to airflow. When air flows over the wings at the correct angle, you get lift, which is what makes a plane fly. If the air is not flowing over the wings properly, the plane can stall, which occurs when it loses lift and begins to fall out of the sky.

The NTSB indicates it will release a full report into the explosion on United Flight 328 after it has completed its investigation.