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调查报告的核心的发现如下：
起飞后不久，飞机左右攻角传感器读数即出现偏差，自动振杆器启动，警告飞行员飞机即将失速：“Shortly after liftoff, the value of the left angle of attack sensor deviated from the right one and reached 74.5 degrees while the right angle of attack sensor value was 15.3 degrees; then after; the stick shaker activated and remained active until near the end of the flight.”
自动飞行系统关闭后，数字飞行记录器显示在没有飞行员输入的情况下，飞机机头四次自动下压。飞行记录器也显示，飞行员反复手动试图反制机头自动下压指令：“After the autopilot disengaged, the DFDR recordedan automatic aircraft nose down (AND) trim command four times without pilot’s input. As a result, three motions of the stabilizer trim were recorded. The FDR data also indicated that thecrew utilized the electric manual trim to counter the automatic AND input.”
飞行员完全按照狮子航空610航班失事后波音所强调的紧急操作流程行事：“The crew performed runaway stabilizer checklist and put the stab trim cutout switch to cutout positionand confirmed that the manual trim operation was not working.” 特别值得一提的是，the stab trim cutout switch 按波音设计应该取消MCAS系统，但遗憾的是未能奏效。
狮子航空610失事后，美国联邦航空管理局（FAA）发布针对波音737 Max 8的适飞指令2018-23-51（Airworthiness Directive 2018-23-51），波音公司也在2018年11月6日提供给埃航新的飞行操作手册重点事项，强调飞机非指令俯冲向下姿态的控制流程:
这一文件显示，飞机的非指令性俯冲会反复发生，除非通过两个STAB TRIM CUTOUT开关予以手动解除。调查报告显示，埃航照单全收，飞行员也全面执行了FAA和波音公司所要求的紧急操作流程，包括启动STAB TRIM CUTOUT开关，却无济于事。
FAA和波音所规范的具体流程如下，包括解除飞机的自动飞行系统和自动油门系统。而埃航302飞行员完全按照这一操作规则行事：
让我们看看调查报告所揭示的飞行员与飞机博命的这惊心动魄几分钟：
首先，左右攻角传感器读数出现偏差：At 05:38:44, shortly after liftoff, the left and right recorded AOA values deviated. Left AOA decreased to 11.1° then increased to 35.7° while value of right AOA indicated 14.94°. Then after, the left AOA value reached 74.5° in ¾ seconds while the right AOA reached a maximum value of 15.3°. At this time, the left stick shaker activated and remained active until near the end of the recording. Also, the air speed, altitude and flight director pitch bar values from the left side noted deviating from the corresponding right side values. The left side values were lower than the right side values until near the end of the recording.
一分钟后，自动飞行系统关闭：At 05:39:55, Autopilot disengaged。这是紧急情况下操作流程的一个步骤。
两秒后，飞行员报告塔台飞机控制出现问题：At 05:39:57, the Captain advised again the First-Officer to request to maintain runway heading and that they are having flight control problems.
三秒后，飞机机头自动下压：At 05:40:00 shortly after the autopilot disengaged, the FDR recorded an automatic aircraft nose down (AND) activated for 9.0 seconds and pitch trim moved from 4.60 to 2.1 units. The climb was arrested and the aircraft descended slightly.
十二秒后，飞行员启动电子配平系统以拉升机头（这也是紧急操作流程的一个步骤）：At 05:40:12, approximately three seconds after AND stabilizer motion ends, electric trim (from pilot activated switches on the yoke) in the Aircraft nose up (ANU) direction is recorded on the DFDR and the stabilizer moved in the ANU directionto 2.4 units. The Aircraft pitch attitude remained about the same as the back pressure on the column increased.
八秒后，机头第二次自动向下：At 05:40:20, approximately five seconds after the end of the ANU stabilizer motion, a second instance of automatic AND stabilizer trim occurred and the stabilizer moved down and reached 0.4 units.
七秒后，机长要求大副与他一起上拉机头：At 05:40:27, the Captain advised the First-Officer to trim up with him.
一秒后，手动电子配平系统启动，机头重新向上：At 05:40:28 Manual electric trim in the ANU direction was recorded and the stabilizer reversed moving in the ANU direction and then the trim reached 2.3 units.
七秒后，飞行员按紧急流程启动stab trim cut-out 以关闭MCAS: At 05:40:35, the First-Officer called out “stab trim cut-out” two times. Captain agreed and First-Officer confirmed stab trim cut-out.
六秒后，机头第三次向下：At 05:40:41, approximately five seconds after the end of the ANU stabilizer motion, a third instance of AND automatic trim command occurred without any corresponding motion of the stabilizer, which is consistent with the stabilizer trim cutout switches were in the ‘’cutout’’position
三秒后，机长大喊三次上拉：At 05:40:44, the Captain called out three times “Pull-up” and the First-Officer acknowledged.
在随后的两分半钟，机头逐渐下压；期间飞行员竭尽全力，但无法控制：From 05:40:42 to 05:43:11 (about two and a half minutes), the stabilizer position gradually moved in the AND directionfrom 2.3 units to 2.1 units. During this time, aft force was applied to the control columns which remained aft of neutral position. The left indicated air speed increased from approximately 305 kt to approximately 340 kt (VMO). The right indicated air speed was approximately 20-25 kt higher than the left.The data indicates that aft force was applied to both columns simultaneously several times throughout the remainder of the recording.
At 05:41:30, the Captain requested the First-Officer to pitch up with him and the First-Officer acknowledged.
At 05:41:46, the Captain asked the First-Officer if the trim is functional. The First-Officer has replied that the trim was not workingand asked if he could try it manually. The Captain told him to try. At 05:41:54, the First-Officer replied thatit is not working.
At 05:42:54, both pilots called out “left alpha vane”.
At 05:43:04, the Captain asked the First Officer to pitch up together and said that pitch is not enough.
飞行员再次反复手动上拉：At 05:43:11, about 32 seconds before the end ofthe recording, at approximately 13,4002 ft, two momentary manual electric trim inputs are recorded in the ANU direction. The stabilizer moved in the ANU direction from 2.1 units to 2.3 units.
九秒钟后，机头再次自动向下俯冲，最后角度高达40度：At 05:43:20, approximately five seconds after the last manual electric trim input, an AND automatic trim command occurred and the stabilizer moved in the AND direction from 2.3 to 1.0 unit in approximately 5 seconds. The aircraft began pitching nose down.Additional simultaneous aft column force was applied, but the nose down pitch continues, eventually reaching 40° nose down. The stabilizer position varied between 1.1 and 0.8 units for the remainder of the recording.
十三秒后，飞行记录仪最后的读数：The last recorded pressure altitude was 5,419 ft on the left and 8,399 ft on the right.
调查报告发布后，埃航发表声明, 埃航302飞行员在最困难的情况下，完全按照波音和FAA紧急操作流程行事：
The preliminary report clearly showed that the Ethiopian Airlines Pilots who were commanding Flight ET302/10 March have followed Boeing's recommended and FAA's approved emergency proceduresto handle the most difficult emergency situation created on the airplane. Despite their hard work andfull compliance with the emergency procedures, it was very unfortunate that they could not recover the airplane from the persistence of nose diving.
美国飞行员联合会发表声明，MCAS失灵是非常严重的紧急事件：
The initial findings of the Ethiopian investigation confirm for us that an MCAS malfunction is a serious emergency and not a benign event
波音公司发布声明称，波音将提供软件补丁修复MCAS问题，发展综合全面的飞行员训练和教育项目，而飞行员总是能够取消MCAS，手动操作飞机：
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 MCASand an associatedcomprehensive pilot training and supplementary education programfor 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.
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