Failed Rivets Prompt FAA to Order Checks of 767s

Federal regulators ordered U.S. airlines Friday to inspect the elevator assemblies on Boeing 767 airliners for damaged controls.

Egyptian officials have pointed to possible tail control problems in the still unsolved crash Oct. 31 of EgyptAir Flight 990, a Boeing 767, which killed all 217 aboard.

But in announcing that it was ordering the inspections, the Federal Aviation Administration said it has received no factual information that the problem is related to the EgyptAir accident.

The agency said it acted after receiving reports of failed shear rivets found in the tail elevator assemblies of three 767 airliners.

Boeing Co. sent operators of the airplanes service bulletins last week recommending the inspections. The newly announced FAA airworthiness directive gives the recommendation the force of law.

The elevator of an aircraft is part of the horizontal tail assembly. When the elevator moves up or down it deflects air, causing the plane’s nose to point up or down.

The problems addressed by the inspection focus on so-called shear rivets. The rivets are designed so that if a jam occurs in one part of the system, the force applied by the pilots can break the rivets and disconnect the jammed part.

This lets the pilots use the non-jammed system to continue the flight safely, the FAA said.

The agency said the inspection calls for a check of rivets on bell crank assemblies. The bell cranks, attached to a hydraulic power control unit, help move the elevators at the rear of the plane.

“Failed shear rivets on two or more bell crank assemblies could produce abnormal elevator movements and consequent reduced controllability or loss of control,” the FAA said.

Airlines must do the inspections within 30 days and replace any problem units. The FAA said the order covers 322 U.S.-registered 767s. There are about 800 of the planes in use worldwide.

The EgyptAir flight from New York suddenly dived into the Atlantic Ocean. Recovered parts have indicated that the left and right elevators were pointing in different directions. These controls are designed to operate together.

Speculation as to the cause of the disaster has focused on the possibility that one of the pilots deliberately plunged the plane into the sea, although the National Transportation Safety Board still is investigating the cause of the crash.

Egyptian authorities have strongly denied that the crash was deliberate and have called for further investigation of the tail controls of the type of aircraft involved.

Investigation details released a week ago indicated that as the plane plunged toward the ocean off the coast of Nantucket Island, Mass., the pilot was struggling to pull back on the controls to raise the nose of the plane.