Our live coverage has ended. Read more about the preliminary report into the crash here.
Capt. Jason Goldberg, spokesperson for the Allied Pilots Association, said today's findings show that the malfunction involving the automated anti-stall software — the Maneuvering Characteristics Augmentation System, or MCAS — is "a serious emergency."
The Allied Pilots Association is American Airline’s pilots union.
Goldberg said pilots remain "cautious and hopeful that the potential fix will be thoroughly vetted and not hurried or fast tracked."
"The APA will remain actively engaged to ensure that the 737 Max will fly again only when all stakeholders are satisfied the aircraft is ready,” he said.
A preliminary report on the Ethiopian Airlines 737 Max 8 accident showed significant similarities to the Lion Air accident, which involved another Boeing 737 Max 8.
In a statement today, Boeing said "safety is a core value for everyone" and maintained that "safety of our airplanes, our customers' passengers and crews is always our top priority."
Keep in mind: The report has not yet been publicly released, but CNN obtained a copy of the report today. The preliminary report does not come to a finding of probable cause. A final report could take as long as a year to produce.
Read Boeing's full statement:
I'd like to reiterate our deepest sympathies are with the families and loved ones of those who lost their lives in the accident," said Boeing Commercial Airplanes President and CEO Kevin McAllister. "We thank Ethiopia's Accident Investigation Bureau for its hard work and continuing efforts. Understanding the circumstances that contributed to this accident is critical to ensuring safe flight. We will carefully review the AIB's preliminary report, and will take any and all additional steps necessary to enhance the safety of our aircraft."
Safety is a core value for everyone at Boeing and the safety of our airplanes, our customers' passengers and crews is always our top priority. Boeing's technical experts continue to assist in this investigation and company-wide teams are working to address lessons from the Lion Air Flight 610 accident in October.
The preliminary report contains flight data recorder information indicating the airplane had an erroneous angle of attack sensor input that activated the Maneuvering Characteristics Augmentation System (MCAS) function during the flight, as it had during the Lion Air 610 flight.
To ensure unintended MCAS activation will not occur again, Boeing has developed and is planning to release a software update to MCAS and an associated comprehensive pilot training and supplementary education program for the 737 MAX.
As previously announced, the update adds additional layers of protection and will prevent erroneous data from causing MCAS activation. Flight crews will always have the ability to override MCAS and manually control the airplane.
Boeing continues to work with the U.S. Federal Aviation Administration and other regulatory agencies worldwide on the development and certification of the software update and training program.
Boeing also is continuing to work closely with the US National Transportation Safety Board (NTSB) as technical advisors in support of the AIB investigation. As a party providing technical assistance under the direction of investigating authorities, Boeing is prevented by international protocol and NTSB regulations from disclosing any information relating to the investigation. In accordance with international protocol, information about the investigation is provided only by investigating authorities in charge.
Ethiopian Airlines CEO Tewolde Gebremariam told CNN that "it looks like" the automated anti-stall software — the Maneuvering Characteristics Augmentation System, or MCAS — was activated before the crash of flight 302.
Some context: The preliminary report, which CNN obtained today, does not specifically name the MCAS stabilization system, but makes it likely the MCAS system pushed the plane into a dive fueled by erroneous angle of attack sensor readings.
Gebremariam added that the preliminary report proved "all the speculators with false allegations" wrong, referring to criticism and doubts over the pilot’s qualifications, adding that the airline has "always been confident" of their pilots.
The CEO went on to add that the Boeing 737 MAX "seems" to have a problem, adding that he thinks Boeing is "trying to do the right thing."
The preliminary report of the Ethiopia Airlines crash paints a graphic picture of the last minutes of the flight, including details about how the two pilots tried in vain to end the dive together.
“The Captain asked the First Officer to pitch up together and said that pitch is not enough,” the report reads. “The data indicates that aft force was applied to both columns simultaneously several times throughout the remainder of the recording.”
The report does not specifically name the Maneuvering Characteristics Augmentation System, which is a stabilization system, but makes it likely the MCAS pushed the plane into a dive fueled by erroneous angle of attack sensor readings. Boeing is currently working on a change to the system’s software.
It says the flight data recorder indicated “automatic aircraft nose down (AND) trim command four times without pilot’s input.”
A note about the report: The report has not yet been publicly released, but CNN obtained a copy of the report today. The preliminary report does not come to a finding of probable cause. A final report could take as long as a year to produce.
The preliminary report on the Ethiopian Airlines 737 MAX accident that killed all 157 on board, shows significant similarities to the Lion Air accident, with the plane’s computer system pushing the nose down four times into a steep 40-degree dive.
About the report: The report has not yet been publicly released, but CNN obtained a copy of the report today. The preliminary report does not come to a finding of probable cause. A final report could take as long as a year to produce.
More details: The similarities between the crashes extend to maintenance and flight issues such as “temporary erratic airspeed and altitude fluctuations.”
As in the Lion Air accident, the left angle of attack indicator, the sensor that drives the Maneuvering Characteristics Augmentation System (or MCAS), recorded an incorrect reading that differed from the right angle of attack indicator by about 20 degrees.
One key difference between the two accidents: The Ethiopian pilots correctly diagnosed the issue and effectively disabled the MCAS system about three minutes before the crash.
They then tried to manually adjust the trim, but found it was “not working.”
About five minutes after takeoff, air traffic controllers granted the pilots’ request to return to the airport.
The last input recorded by the flight data recorder: The plane reaching 500 knots.
Ethiopian aviation authorities discussed a preliminary report on the Ethiopian Airlines crash at a press conference Thursday, concluding that the pilots did everything they were trained to do to regain control of the plane.
The main takeaways are as follows:
- Software may have played a role in the crash: The automated anti-stall software called the Maneuvering Characteristics Augmentation System (MCAS) is under suspicion.
- No sign yet of a problem with the sensor: Although it doesn't rule out a possibly faulty sensor, a top Ethiopian accident investigator said Thursday they have not identified any damage to the aircraft's sensors that could have contributed to the crash.
- MCAS training didn't appear to help prevent the crash: Overall, Ethiopian aviation authorities are making it clear that pilot error does not appear to be an issue in the crash and the pressure is now on Boeing to ensure the 737 Max is safe.
CNN aviation analyst Mary Schiavo has criticized the Federal Aviation Administration (FAA) for its oversight of Boeing.
The FAA has come in for criticism for its role in approving the Boeing 737 Max aircraft that were involved in fatal crashes in Indonesia and Ethiopia.
Schiavo questioned the quality of the FAA's oversight of Boeing and claimed that the administration's previous reputation for excellence has been tarnished.
There should be triple redundancy for different systems to ensure safety, said Schiavo, but the MCAS software systems aboard both crashed Max 8s were fed by only one angle of attack (AOA) sensor.
Schiavo claims this reliance on just one sensor begs the question as to why Boeing didn't originally build the planes with two AOA sensors, and why the FAA did not require it.
Another issue with the 737 Max is its tendency to point slightly upward due to the use of larger engines which altered its aerodynamics compared to previous 737s.
Boeing tried to remedy this using the MCAS software, but Schiavo questioned why the FAA approved a software fix for the issue.
"Why was MCAS put in to solve what looks like a center of gravity problem, a pitch up problem?" she said.
During a press conference Thursday, Ethiopian investigators looking into the Ethiopian Airlines crash in March said the pilots were qualified and operated the plane as Boeing intended, even down to trying to override an anti-stall software known as MCAS.
CNN anchor and aviation expert Richard Quest believes that Boeing is under pressure following the press conference, despite its excellent reputation.
"The focus does turn firmly, fairly and squarely onto Boeing," said Quest.
Boeing has a superb reputation, he added, but the MCAS system was an "operating force" in both the Ethiopian Airlines and Lion Air crashes and the company has to "restore confidence in their planes."
"The onus is on Boeing."