Boeing’s bad bolt caused emergency MB landing

A single bolt improperly installed by U.S. aerospace company Boeing Co. caused Korea’s presidential jet to make an unprecedented emergency landing in March, Air Force investigators concluded yesterday.

The presidential jet, a Boeing 747-400, with President Lee Myung-bak and first lady Kim Yoon-ok on board, was forced to land at Incheon International Airport, west of Seoul, on March 12 while heading to the United Arab Emirates for an official visit.

Although no passengers suffered injuries and the presidential jet resumed its flight about two hours after repairs on a malfunction in the plane’s ventilation system, it marked the first emergency landing by a presidential jet in Korea.

The investigation attributed the emergency landing to a bolt in the plane’s air-distribution system that was “incorrectly installed by Boeing.”

“We found that Boeing incorrectly installed the bolt when it manufactured the 747-400 plane,” Air Force Col. Choi Young-hoon told reporters. “Boeing’s faulty assembly is responsible for the landing incident.”

The incorrectly assembled torque arm bolt caused one of three air-inlet doors in the plane’s main cabin to rupture and produce noise, Choi said.

“To prevent the recurrence of such an accident, the Air Force will conduct monthly safety checks on the presidential jet,” Choi said.

Korea’s Air Force and Boeing jointly carried out the investigation, Choi said.

In a statement, Boeing admitted it was responsible for the faulty assembly.

“We are revising the aircraft maintenance manual to more clearly identify the proper reinstallation of the torque arm bolt,” the statement said. “We will continue to review other fleet actions as appropriate.”

“As a result, we are reviewing the data to determine possible actions for our production system and the in-service fleet,” Boeing said.

The Blue House leased the Boeing aircraft, manufactured in 2001, from Korean Air last year under a four-year contract worth 140 billion won ($130.2 million).

Kang Young-shik, executive vice president of Korean Air, said the company plans to ask Boeing to pay compensation for direct and indirect damage caused by the emergency landing.

Korean Air is responsible for maintenance and in-flight services for the presidential jet, while the Air Force supervises maintenance work.

Yonhap