<story><title>FAA Finds New Risk on 737 Max, Orders Boeing to Make Changes</title><url>https://www.bloomberg.com/news/articles/2019-06-26/faa-finds-new-risk-on-737-max-and-orders-boeing-to-make-changes</url></story><parent_chain><item><author>th0ma5</author><text>To be fair, ignoring user input could have potentially have saved Air France 447... I mean I actually can&amp;#x27;t think of an automated fool proof system that would&amp;#x27;ve fixed 447, but incorrect input was a major factor.</text></item><item><author>rjvehn</author><text>There are a myriad of issues that put the planes at risk, but I think that the fact that when the control system (MCAS) is engaged causes it to ignore feedback is the biggest issue of all.&lt;p&gt;&amp;quot;But with the MCAS activated, said Fehrm, those breakout switches wouldn’t work. MCAS assumes the yoke is already aggressively pulled back and won’t allow further pullback to counter its action, which is to hold the nose down.&lt;p&gt;Fehrm’s analysis is confirmed in the instructions Boeing sent to pilots last weekend. The bulletin sent to American Airlines pilots emphasizes that pulling back the control column will not stop the action.&lt;p&gt;Fehrm said that the Lion Air pilots would have trained on 737 simulators and would have learned over many years of experience that &lt;i&gt;pulling back on the yoke stops any automatic tail maneuvers pushing the nose down.&lt;/i&gt;&amp;quot; [0].&lt;p&gt;If you bought a new computer, how pissed off would you be if you lost data not because of a hard-drive failure, but because of a weird design decision of the 1 penny caps lock key? Imagine spending the time to setup a proper RAID system and losing everything because of a &lt;i&gt;design decision&lt;/i&gt; in the keyboard.&lt;p&gt;I mean if the media keeps reporting about the small stuff that&amp;#x27;s wrong, it&amp;#x27;s going to make people go &amp;quot;well planes are complex and things happen&amp;quot; and almost ignore the seriousness of a design decision that ignores user input.&lt;p&gt;[0]: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.seattletimes.com&amp;#x2F;business&amp;#x2F;boeing-aerospace&amp;#x2F;faa-evaluates-a-potential-design-flaw-on-boeings-737-max-after-lion-air-crash&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.seattletimes.com&amp;#x2F;business&amp;#x2F;boeing-aerospace&amp;#x2F;faa-e...&lt;/a&gt;</text></item></parent_chain><comment><author>halter73</author><text>IIRC, the cockpit voice recording included a comment from one of the co-pilots about how pulling back on the yoke couldn&amp;#x27;t cause a stall. The assumption was that the Airbus&amp;#x27;s fly-by-wire system would prevent it and ensure the aircraft still climbed as long as the pilot held back on the stick.&lt;p&gt;The co-pilot apparently didn&amp;#x27;t realize that the sensor issue that disabled the autopilot also disabled the stall prevention. And that&amp;#x27;s despite an audible &amp;quot;STALL&amp;quot; warning being repeated in the background.&lt;p&gt;The captain was not in the cockpit when the whole situation started, but as he re-entered the cockpit during the stall he saw one of the co-pilots holding back on the yoke and told him to push the yoke forward to prevent the stall. The co-pilot followed the instructions, but only for a few seconds before pulling the yoke back again.&lt;p&gt;All of this is to say if the plane hadn&amp;#x27;t been &lt;i&gt;known&lt;/i&gt; to ignore user inputs in most situations, the co-pilot might not have assumed the Airbus would do the right thing and climb no matter what when pulling back on the yoke. So in a sense, &lt;i&gt;never&lt;/i&gt; ignoring user inputs might have also saved Air France 447.</text></comment>
<story><title>FAA Finds New Risk on 737 Max, Orders Boeing to Make Changes</title><url>https://www.bloomberg.com/news/articles/2019-06-26/faa-finds-new-risk-on-737-max-and-orders-boeing-to-make-changes</url></story><parent_chain><item><author>th0ma5</author><text>To be fair, ignoring user input could have potentially have saved Air France 447... I mean I actually can&amp;#x27;t think of an automated fool proof system that would&amp;#x27;ve fixed 447, but incorrect input was a major factor.</text></item><item><author>rjvehn</author><text>There are a myriad of issues that put the planes at risk, but I think that the fact that when the control system (MCAS) is engaged causes it to ignore feedback is the biggest issue of all.&lt;p&gt;&amp;quot;But with the MCAS activated, said Fehrm, those breakout switches wouldn’t work. MCAS assumes the yoke is already aggressively pulled back and won’t allow further pullback to counter its action, which is to hold the nose down.&lt;p&gt;Fehrm’s analysis is confirmed in the instructions Boeing sent to pilots last weekend. The bulletin sent to American Airlines pilots emphasizes that pulling back the control column will not stop the action.&lt;p&gt;Fehrm said that the Lion Air pilots would have trained on 737 simulators and would have learned over many years of experience that &lt;i&gt;pulling back on the yoke stops any automatic tail maneuvers pushing the nose down.&lt;/i&gt;&amp;quot; [0].&lt;p&gt;If you bought a new computer, how pissed off would you be if you lost data not because of a hard-drive failure, but because of a weird design decision of the 1 penny caps lock key? Imagine spending the time to setup a proper RAID system and losing everything because of a &lt;i&gt;design decision&lt;/i&gt; in the keyboard.&lt;p&gt;I mean if the media keeps reporting about the small stuff that&amp;#x27;s wrong, it&amp;#x27;s going to make people go &amp;quot;well planes are complex and things happen&amp;quot; and almost ignore the seriousness of a design decision that ignores user input.&lt;p&gt;[0]: &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.seattletimes.com&amp;#x2F;business&amp;#x2F;boeing-aerospace&amp;#x2F;faa-evaluates-a-potential-design-flaw-on-boeings-737-max-after-lion-air-crash&amp;#x2F;&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.seattletimes.com&amp;#x2F;business&amp;#x2F;boeing-aerospace&amp;#x2F;faa-e...&lt;/a&gt;</text></item></parent_chain><comment><author>cyberferret</author><text>Basic rudimentary &amp;#x27;stick and rudder&amp;#x27; flying skills was a big factor in AF447&amp;#x27;s crash. All old school pilots know that when you aircraft is in a nose high stall condition, you &lt;i&gt;never&lt;/i&gt; keep pulling back on the stick, but instead push it forwards to lower the nose and get the wings flying again.&lt;p&gt;The fact that the co-pilot in question kept holding the stick to the back stops was the main reason that the aircraft wallowed into the sea.  Weirdly, he &lt;i&gt;did&lt;/i&gt; let go of the stick for a brief few seconds, which was the only time during the harrowing descent that the aircraft started to behave normally, but then he pulled it back and held it back right up until impact.&lt;p&gt;Yep, the aircraft could have ignored these inputs, but the inputs are counter to what any reasonably skilled pilot would have done. (Note: Different to the MAX crashes where pulling back on the stick under speed IS the accepted way to stop a descent.)</text></comment>