Transcript for Sensor damage led to Ethiopian Airlines crash: Officials
He's been surging. First we begin with breaking news on that fatal Boeing flight. Ethiopian officials now say the plane's black boxes reveal the pilots did use the proper procedures before the crash. David Kerley at Reagan airport has the latest. Reporter: It's not just ethiopian airlines say its pilots were in full compliance when the safety system in the Boeing max misfired. They couldn't regain control but two sources are telling ABC news that's not the full story. Ethiopian authorities this morning saying their preliminary investigation points to the anti-stall system in the Boeing 737 max which crashed killing all on board. The crew performed all the procedures repeatedly provided by the manufacturer, but was not able to control the aircraft. Reporter: But Ethiopia did not immediately release or post its report nor answer questions posed by ABC news' reporting on the crash. Two aviation sources close to the investigation telling us a sensor apparently damaged in takeoff started a chain of events which led to the crash. That one sensor outside the cockpit was likely hit by a bird or foreign object like in the first crash lion air in Indonesia, bad data from that sensor then engaged the anti-stall system mcas which nose downed the jet. As we learned in a simulator the procedure for pilots is to use a thumb button to electronically nose up the plane first, it's called trimming the aircraft. If that fails, Boeing's emergency procedure calls to shut off the power to the motors which nose up or down the plane. One source says the pilots went immediately to shut off the system before pulling the nose up and then for some still unknown reason turned the system back on which is not part of the procedure. The lead ethiopian investigator asked about that did not provide an answer but he disputed the report of the sensor being damaged by a bird or foreign object. We didn't find any information regarding that on the aircraft. It doesn't indicate that there is that. Reporter: Now, the FAA and the NTSB contributed to this report. While that short newscast or news conference was held we have not actually seen the report we have not seen the data nor the preliminary report. Cecilia. David Kerley, thank you. Let's bring in colonel Steve ganyard. Steve, we just heard the headline there from David. The ethiopians are essentially blaming Boeing saying the pilots followed the instructions for the plane, but we had heard that the crew really struggled to regain control of that plane. So what's the truth here? Cecilia, unfortunately, this press conference today didn't move the ball forward. We really didn't learn much more about what caused the mishap. We had two comments, one from a transportation minister who said some very reasonable things that there's a problem with this airplane that needs to be fixed. The other were the comments from the CEO of the airline. His comments are questionable. Our very well sourced reporting says his pilots did not comply with the appropriate procedures. They did switch off the system that was giving a problem but for some reason they switched that system back on which caused the airplane to nose into the ground. So at the end of this press conference we really don't know much more and we'reoing to have to continue on with that software fix that will make sure this doesn't happen again. As we've been reporting meantime, back here at home, hundreds of these 737 max 8s remain grounded. Where do we go now? The software fix is still in work. The FAA and Boeing thought it was going to be out this week. But given the congressional pressure on the FAA to make sure this is really fixed and that this software fix is not being rushed, they're taking double-check and triple check to make sure the software fix is appropriate and that this airplane never has a problem like this again. Okay, Steve ganyard, thank you. Still so many questions. They don't know about the report, they haven't seen the data yet so a lot of questions. They have got to get the software fix right.
This transcript has been automatically generated and may not be 100% accurate.