The Boeing 737-800 is one of the most common aircraft in the world

Investigators are trying to figure out what caused a Jeju Air flight to land on its belly without the landing gear down at South Korea’s Mueang International Airport, killing all but two of the 181 people on board when the plane burst into flames in the country’s worst air disaster the country. decades later.

South Korea’s acting president, Choi Sang-mok, ordered a state of emergency check countries Boeing 737-800, the type of aircraft used on fatal Jeju Air flight 7C2216.

The Boeing 737-800 is one of the most frequently used aircraft in the world, and it has a high safety record. It predates the Boeing 737 Max, the type involved in two fatal crashes in 2018 and 2019 that killed all 346 people on board those flights. The 737 Max was grounded for nearly two years.

According to aviation data company Cirium, there are about 4,400 737-800 aircraft in operation worldwide. This means that the model represents about 17% of the world’s fleet of commercial jet passenger aircraft.

According to Cirium, the average age of the global 737-800 fleet is 13 years, and the last aircraft in the series were delivered about five years ago.

Jeju Air has received the plane that crashed this weekend in 2017. It was previously operated by the European discount airline Ryanair, according to Flightradar24. The plane that crashed was about 15 years old.

Aerospace experts say it’s unlikely that researchers will find a problem with the long-range plane’s design.

“The idea that they would find a design flaw at this point is unthinkable,” said Richard Aboulafia, managing director of AeroDynamic Advisory, an aerospace consulting firm.

A full investigation could take more than a year, and the unusual incident has raised more questions than answers, such as why the landing gear was not deployed. Even with a hydraulic failure, Boeing 737-800 pilots can reset the landing gear manually.

One theory involves a possible bird strike that disabled the engines.

“If it happened at the altitude they were at, they may not have had time to go through the emergency checklists,” said Jeff Guzzetti, a retired investigator with the US National Transportation Safety Board and the US Federal Aviation Administration. He also said that if the plane had not hit a solid wall at the end of the runway, the crash could have been survivable.

The NTSB leads a U.S. investigative team that also includes Boeing and the FAA, since the aircraft was manufactured and certified in the United States.

According to international protocols, the general investigation will be conducted by the country where the incident occurred.