If you are planning a trip away over the summer months, now that university has let out, I would advise some caution in choosing where you are going. Not because of the countries. Be careful of the planes.
A software vulnerability in the new Boeing 787 Dreamliner jet has the potential to cause pilots to lose control of the aircraft. Even more concerning than the fact that pilots could lose control, is that it could happen in mid-flight, this warning comes not just from a layperson but from the Federal Aviation Administration.
The bug, which is either a classic integer overflow, or one very much resembling an overflow, resides in one of the electrical systems on board the new aircraft, the area affected is responsible for generating power, according to memo the FAA issued last week.
The vulnerability, which Boeing, to their credit, reported to the FAA, is triggered when a generator has been running continuously for a little more than eight months. As a result, FAA officials have adopted a new airworthiness directive (AD) that airlines will be required to follow, at least until the bug can be adequately dealt with or outright fixed.
“This airworthiness directive was prompted by the determination that a Model 787 airplane that has been powered continuously for 248 days can lose all alternating current (AC) electrical power due to the generator control units (GCUs) simultaneously going into failsafe mode,” the memo stated.
The memo concluded that, “This condition is caused by a software counter internal to the GCUs that will overflow after 248 days of continuous power. We are issuing this AD to prevent loss of all AC electrical power, which could result in loss of control of the airplane.”
The memo went on to say that Dreamliners have four main generator control units associated with the engine mounted generators. If all of them were powered up at the same time, “after 248 days of continuous power, all four GCUs will go into failsafe mode at the same time, resulting in a loss of all AC electrical power regardless of flight phase.” In other words if the plane’s engines were all powered up at the same time and run continuously, an unlikely event, they would all fail at the same time. This kind of catastrophic failure can only really lead to bad things, like say a plane ploughing in to the ground.
Boeing is in the process of developing a software upgrade that will remedy the unsafe condition though, and will hopefully implement it as quickly as possible preventing any of these problems from having a real human cost. This however is not the first problem facing Boeing concerning theses planes, the new model plane had previously experienced a battery problem, this battery issue lead to a fire while one aircraft was parked on a runway.
Boeing is one of the largest airplane manufactures globally and they will solve this problem quickly but one has to be worried that a problem as potentially massive as this managed to slip by the testing prior to these planes going into service. Let’s hope that Boeing do not have any more mechanical or technical issues and to all of you who will eventually fly in one, be safe.