April 30, 2013
Boeing’s 787 Dreamliner was cleared to fly last Thursday. The Federal Aviation Administration lifted a ban on passenger flights that it imposed in January after two battery malfunctions in the new jets raised serious safety concerns. The FAA approved Boeing’s plan to modify the 787 battery system and flights are expected to resume within days.
So, the FAA says the Dreamliner is safe. But will travelers buy that? We think so. Here’s why.
The innovative, fuel-efficient Dreamliner ran into trouble because it is the first passenger jet to make extensive use of lithium-ion batteries. Those batteries, widely used in laptops and cellphones, have a history of occasionally overheating. When Boeing designed the aircraft, the company and its suppliers devised a series of tests to ensure the battery system would be safe for flight. The tests, done under the oversight of the FAA, suggested the planes could go for millions of hours without encountering any battery problem.
In practice, however, problems occurred not long after the Dreamliner entered service. An empty plane parked on a runway in Boston filled with smoke. A plane full of passengers in Japan had to be evacuated.
So it was back to the drawing board. Boeing, its suppliers, federal regulators and their global counterparts developed new tests to figure out what caused the batteries to fail. Boeing hired battery experts from outside the aviation industry to evaluate the testing procedures and propose solutions.
The exact cause of the battery failures never was identified. When complex systems fail, it can be difficult to pinpoint a simple reason. Boeing, though, developed a way to protect the passengers and the planes.
The company redesigned the battery system so if one cell short-circuited, others would not. Short circuits are the most likely reason that an undamaged battery would overheat. Boeing also added high-grade insulation between cells so overheating in one part of the battery would not spread to other parts.
Perhaps most important from the passenger standpoint, Boeing encased the battery system in a sealed steel enclosure, vented outside the aircraft. So even if a battery failure occurred, the aircraft wouldn’t be damaged. Smoke or fire would not spread.
As part of the testing, according to news reports, Boeing went so far as to simulate explosions inside the steel case. The enclosure is so secure that passengers would not notice if a failure occurred. The aircraft doesn’t rely on the batteries to stay in the air.
These incidents were alarming, but no one was hurt. The damage to the aircraft was isolated in the battery compartment.
The credibility of Boeing, the FAA and the airlines that fly the Dreamliner is on the line. A battery problem that damaged a plane or created a safety threat would be a huge blow to the airline industry. There’s a big incentive to get this right.
Investors have shown confidence. Boeing’s stock has jumped this year, despite the widely reported troubles.
The airlines have shown confidence, too. Despite the grounding of the fleet and the delays in deliveries, airlines did not cancel the hundreds of orders they placed for the Dreamliner.
Who’s left to convince? The people who fill the seats.