On Thursday, in an effort to determine the cause of the crash of Flight 302, Ethiopian Airlines delivered the aircraft’s data recorders to Paris for analysis. The flight from Addis Ababa to Nairobi crashed shortly after takeoff on Sunday, killing 157, and the plane’s flight data recorder and the cockpit voice recorder were recovered on Monday. Colloquially known as the “black boxes,” these two crucial data repositories will be examined by France’s Bureau of Enquiry and Analysis for Civil Aviation Safety, or BEA. Why were the black boxes from an Ethiopia-based airline sent to Paris?
The International Civil Aviation Organization, which sets the standards for aircraft accident investigations, says that the country where an incident occurs is in charge of the investigation. But according to Al Jazeera, Ethiopia doesn’t have the tools to analyze the black boxes, which capture voices and noises from the cockpit and data about the aircraft, such as altitude and speed, and help investigators determine the cause of a crash. The Ethiopian government asked Germany to analyze the black boxes, but according to CBS, the Germans also lacked the necessary software. Experts say a conflict of interest likely stopped the boxes from being sent to the U.S., since Boeing, which manufactures the 737 Max 8 aircraft that crashed, is based in the States.
Black boxes are designed to withstand extreme heat, impact, and pressure, but the one from Flight 302 was badly damaged. Extracting data from them is a delicate process, and processing the data requires specific decoding software. Specialists must then sort through the information they obtain and analyze it, trying to piece together possible technical causes of a crash. The level of damage for the Ethiopian Airlines flight meant “the investigators need to be able to directly read into the memories of the black boxes, because the standard interfaces probably cannot be used,” says Eric Feron, professor of aerospace software engineering at Georgia Tech.
Feron says France’s BEA is among the agencies with capabilities for extracting information from damaged devices, and the Associated Press notes the agency has “extensive experience” in plane crash investigations. (The U.S. is sending investigators to assist.) He notes that black boxes are a niche market, and most major commercial aircraft black box manufacturers have been based in the U.S. or France. When seeking certification for their products, these manufacturers must provide “evidence that the black box can be reliably interrogated by a number of third parties, including accident investigation teams,” Feron says. “[It’s] like brain surgery, something uncommon and very hard to do. Think of the teams having to do something similar to recovering the contents of your hard disk after a fatal computer crash, but not being allowed to mistakenly erase stuff.”
According to Feron, decoding software can usually be made available to countries that request it. But he believes that this particular investigation was sufficiently critical that the black boxes went to the team that happened to already have the correct software—the French. Several countries, including the U.S., have grounded the Boeing 737 Max 8 after data suggested similarities between the Ethiopian Airlines crash and one involving a Lion Air jet that killed 189 in October.
Aircraft accident investigations can often take years to complete, since the outcome is critical for victims’ families, aircraft manufacturers, airlines, and government regulators. Deutsche Welle reported that the BEA would begin its analysis on Friday, and preliminary conclusions will take several days. Airlines, anxious travelers, and more are undoubtedly eager for any information about the cause of the Ethiopian Airlines crash. Anything the investigators may unearth inside the black boxes in the coming days will prove crucial.