The Federal Aviation Administration ordered U.S. airlines on Monday to inspect Boeing 787s for lightning damage to systems that control the composite-plastic jetliner’s ascent and descent, heightening pressure on the planemaker as it scrambles to return another, more popular aircraft to commercial service.
The agency’s airworthiness directive follows more than a year of input on a measure requested by the Chicago-based planemaker after it learned that lightning might cause leaks of hydraulic fluid used to move ailerons, strips located on the wings that let the plane bank left or right, and elevators, flaps on the tail that move the plane’s nose up or down.
The order, which affects 82 airplanes operated by U.S. carriers, comes as Boeing works on a patch to computer software faulted in two overseas crashes of its best-selling 737 Max that killed more than 300 people. After the second accident, involving an Ethiopian Airlines flight in mid-March, the FAA followed its international counterparts in grounding the aircraft, a move that snarled flight schedules and halted deliveries.
The impact of the 787 order, designed to eliminate “airplane flutter” that might occur if the leaks were accompanied were other hydraulic failures, is less severe. Airlines will be required to conduct the inspections every nine months or 6,000 flight hours if their planes use power-control units susceptible to the lightning strikes.
[Related: Boeing finds second software problem on grounded 737 MAX airliner]
The FAA’s order makes mandatory a recommendation that Boeing had previously made to airline customers, said Paul Bergman, a spokesman for the planemaker. The company “implemented a design change to fix the issue in 2017,” he added.
Marketed as the Dreamliner, the 787 was sidelined for three months in 2013 after issues with a lithium-ion battery caused one unit on a parked aircraft to catch fire.
Six years later, safely returning the 737 Max to commercial service is a top priority, Boeing CEO Dennis Muilenburg said last week. The latest version of one of the airline industry’s most widely flown planes, the jetliner was sidelined after flight data from the downed Ethiopian Airlines plane showed choppy ascents and descents during takeoff, mirroring those before a Lion Air crash in Indonesia on Oct. 29.
In the Indonesian crash, a malfunctioning sensor fed incorrect data on the airliner’s ascent vector to a computer system that attempted to lower the angle to avoid a stall, officials said. That prompted a struggle between computer software known as the Maneuvering Characteristics Augmentation System, or MCAS, and the pilot, who ultimately lost control of the aircraft.
All 189 people aboard were killed. The fact that Boeing hadn’t yet completed a software patch that the FAA mandated afterward was part of what prompted the high level of concern when the Ethiopian Airlines crash outside the capital of Addis Ababa in early March killed all 157 passengers and crew.
The agency initially expected to approve a software fix by April, but Boeing stretched out the timeline to ensure all “pertinent issues” were addressed.
The planemaker has garnered more than 4,600 orders for the single-aisle 737 Max, though just 67 of the aircraft are flown in the U.S. and fewer than 400 worldwide. The planemaker only began delivering the plane in 2017 and was working to ramp production up to 57 a month, which would have netted a potential $30 billion in sales this year, prior to the Ethiopian crash.
