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New Evidence in Ethiopian Crash Points to Connection to Earlier Disaster New Evidence in Ethiopian 737 Crash Points to Connection to Earlier Disaster
(about 4 hours later)
WASHINGTON — Investigators at the crash site of the doomed Ethiopian Airlines flight have found new evidence that points to another connection to the earlier disaster involving the same Boeing jet.WASHINGTON — Investigators at the crash site of the doomed Ethiopian Airlines flight have found new evidence that points to another connection to the earlier disaster involving the same Boeing jet.
The evidence, a piece of the Boeing 737 Max 8 jet that crashed in Ethiopia last weekend killing 157 people, suggests that the plane’s stabilizers were tilted upward, according to two people with knowledge of the recovery operations. At that angle, the stabilizers would have forced down the nose of the jet, a similarity with the Lion Air crash in October.The evidence, a piece of the Boeing 737 Max 8 jet that crashed in Ethiopia last weekend killing 157 people, suggests that the plane’s stabilizers were tilted upward, according to two people with knowledge of the recovery operations. At that angle, the stabilizers would have forced down the nose of the jet, a similarity with the Lion Air crash in October.
The causes of both crashes are still under investigation, but the new evidence potentially indicates that the two planes both had problems with a newly installed automated system on the 737 Max jet intended to prevent a stall.The causes of both crashes are still under investigation, but the new evidence potentially indicates that the two planes both had problems with a newly installed automated system on the 737 Max jet intended to prevent a stall.
This evidence ultimately contributed to American regulators’ decision to ground the 737 Max this week, according to the two people who spoke on the condition of anonymity. The Federal Aviation Administration said it had found physical evidence from the Ethiopian crash that, along with satellite tracking data, suggested similarities between the two crashes.This evidence ultimately contributed to American regulators’ decision to ground the 737 Max this week, according to the two people who spoke on the condition of anonymity. The Federal Aviation Administration said it had found physical evidence from the Ethiopian crash that, along with satellite tracking data, suggested similarities between the two crashes.
The new evidence found at the crash site in Ethiopia, a piece of equipment known as a jackscrew, controls the angle of the horizontal stabilizers. The stabilizers can be triggered by the automated system, the maneuvering characteristics augmentation system or MCAS. The new evidence found at the crash site in Ethiopia, a piece of equipment known as a jackscrew, controls the angle of the horizontal stabilizers. The stabilizers can be triggered by the automated system known as MCAS.
The stabilizers could have been tilted upward for other reasons. The investigation is in the early phases, and authorities in France are analyzing the black boxes of the Ethiopian Airlines plane for more information.The stabilizers could have been tilted upward for other reasons. The investigation is in the early phases, and authorities in France are analyzing the black boxes of the Ethiopian Airlines plane for more information.
Indonesian and American authorities are also focusing on whether MCAS contributed to the Lion Air crash that killed 189 people. In that crash, the automated system, possibly based on faulty sensor readings, may have repeatedly pushed the nose of the Lion Air plane down, creating a struggle between the new flight-control system and the pilots. Indonesian and American authorities are also focusing on whether MCAS contributed to the Lion Air crash that killed 189 people in October. In that crash, the automated system, possibly based on faulty sensor readings, may have repeatedly pushed the nose of the Lion Air plane down, creating a struggle between the new flight-control system and the pilots.
After the Lion Air crash, Boeing maintained that its planes were safe, and the 737 Max aircraft continued to crisscross the planet. But in the background, the company had been working on a software update for the planes that would address some of the issues encountered in the October accident.
The automated system in question activates if one of two sensors mounted on an aircraft’s exterior says the nose is too high. That means a malfunction with one of the sensors could force the plane in the wrong direction. Boeing’s software update would require data from both sensors for MCAS to kick in, according to pilots at several major airlines and two lawmakers briefed on the matter.
Such a single point of failure on a modern jet “is very, very rare,” and far riskier than having backup systems, said Michael Michaelis, the top safety official at American Airlines’ pilots union and a 737 captain.
Pilots at United and American Airlines said they still generally felt comfortable flying the 737 Max jets, in part because they were now aware of the new automated system. Boeing did not fully disclose the system to pilots until after the Lion Air crash.
Boeing said the software fix would “make an already safe aircraft even safer.” The F.A.A. has said it expects to ask airlines by “no later than April” to incorporate the software fix.