Sunday, January 26, 2014

Boeing 767 Is Subject to New FAA Order: Regulator Demands Safety Checks, Modifications for Flight-Control Mechanism

The Wall Street Journal

By Andy Pasztor

Jan. 26, 2014 1:15 p.m. ET

U.S. regulators are set to order additional safety checks of more than 400 Boeing Co. 767 jets, citing hazards from movable tail sections that can jam and potentially cause pilots to lose control of the aircraft.

Slated to be published in Monday's Federal Register, the Federal Aviation Administration's directive calls for enhanced inspections of horizontal flight-control surfaces called elevators, along with modification and replacement of certain bolts and other parts used to control them. Elevators help move the noses of planes up and down.

The FAA order says "failures or jams in the elevator system" can result "in a significant pitch upset and possible loss of control."

While damaged bolts and improperly working elevators haven't been identified as the cause of any 767 accidents, nagging questions about their reliability underscore the challenges of using piecemeal solutions to address serious safety issues affecting such a widely-used fleet.

The hazards initially were identified in the summer of 2000, when the FAA ordered enhanced checks to identify damaged bolts or problematic elevator mechanisms. The inspections were considered an interim response.

Since then, inspections have been tightened and Chicago-based Boeing has issued half a dozen service bulletins. Eventually, the plane maker designed a permanent fix, which the FAA is now ordering.

The latest agency action, which becomes effective in March, requires U.S. carriers to swap out suspect parts within six years. Foreign regulators are expected to follow with similar directives affecting several hundred other 767s flying world-wide.

Boeing and the FAA didn't have any comment.

The FAA in August 2000 ordered the first round of special inspections of the bolts and mechanical links, called bellcranks, that move elevators on the twin-engine, widebody jets. The rivets are designed so that if a jam occurs in one part of the system, pilots can still control the elevators.

At the time, FAA and Boeing experts worried that routine tests weren't adequate to detect problems. The FAA also determined that rivet failures affecting two or more of the six bellcranks on a 767 could lead to abnormal or even uncommanded movement of the hydraulically-driven surfaces.

A year later, the FAA ordered separate but related tests to ensure elevator controls were rigged properly. In 2007 and 2008, Boeing recommended a series of further repetitive tests to ensure proper elevator operation.

The FAA's new directive gives airlines credit for voluntarily complying with those earlier service bulletins. But it also enhances inspections, including new mandatory tests. Coupled with installation of redesigned parts, according to the FAA, the directive "will further reduce the probability of the unsafe condition" identified more than a decade ago.

The FAA is acting despite various industry objections. United Airlines. now a unit of United Continental Holdings Inc.,  argued that Boeing's service bulletins make the safety directive unnecessary. But without binding mandate, agency officials determined they "have no way of determining the level of airline" compliance.

The new tests, some required within 6,000 hours of flight time, are projected to cost airlines millions of dollars. But the FAA said some of the replacement and overhaul work is expected to be covered by Boeing.


No comments:

Post a Comment