Two Boeing 737 MAX 8 pilots reported nosedives after engaging autopilot in 2018, data reveals
Updated about 4 hours ago

Airline pilots on at least two US flights have reported that an automated system seemed to cause their Boeing 737 MAX 8 planes to tilt down suddenly.

Key points:
Two pilots separately reported to NASA that they suspected automated controls in their Boeing 737 MAX planes were faulty
Both planes suddenly tilted mid-flight but were quickly corrected
North American carriers have continued to fly the 737 MAX, despite groundings elsewhere
In reports filed last year in a database compiled by NASA, the pilots said that soon after engaging the autopilot on their planes, the nose tilted down sharply.

In both cases they recovered quickly after disconnecting the autopilot, they said.

The problem as described by the pilots, however, did not appear related to a new automated anti-stall system that was suspected of contributing to a deadly October crash in Indonesia.

Boeing's newest version of its most popular plane, the 737 MAX, is again in the spotlight after another deadly crash minutes after take-off.

The MAX 8 is at the centre of a widening ban — now involving more than 40 countries — following a second fatal crash, this time in Ethiopia, in less than five months.

In the US, however, the Federal Aviation Administration (FAA) and respective carriers continue to permit the planes to fly.

Overnight US President Donald Trump said modern planes were "too complex to fly", and a Reuters source claimed the US President spoke to Boeing CEO Dennis Muilenburg after his comments.

American Airlines and Southwest Airlines operate the 737 MAX 8, and United Airlines flies a slightly larger version, the MAX 9.

All three carriers vouched for the safety of MAX aircraft on Wednesday.

Unclear if reports led to FAA action
Groundings by country:
Australia
Bermuda
China
European Union
Fiji
India
Indonesia
Kuwait
Malaysia
Norway
Oman
Singapore
Turkey
United Arab Emirates
United Kingdom
Vietnam
The pilot reports were voluntary and did not publicly reveal the names of the pilots, the airlines or the location of the incidents.

It was unclear whether the accounts led to any action by the FAA or the pilots' airlines.

In one report, an airline captain said that immediately after putting the plane on autopilot the co-pilot called out "descending", which was followed by an audio cockpit warning, "Don't sink, don't sink!"

The captain immediately disconnected the autopilot and resumed climbing.

"With the concerns with the MAX 8 nose down stuff, we both thought it appropriate to bring it to your attention," the captain wrote.

The captain added that the "best guess from me is airspeed fluctuation" due to a brief weather system overwhelming the plane's automation.

Low-altitude warning system was blamed in both reports
An aircraft cockpit with a number of dimly-lit controls look out to a sky above clouds at sunset.
PHOTO: Newer versions of Boeing's 737 series have incorporated greater automated controls. (Flickr: Frans Zwart)
On another flight, the co-pilot said that seconds after engaging the autopilot, the nose pitched downward and the plane began descending at 1,200 to 1,500 feet (365 to 457 metres) per minute.

As in the other flight, the plane's low-altitude-warning system issued an audio warning.

The captain disconnected autopilot and the plane began to climb.

The pilots talked it over later, "but can't think of any reason the aircraft would pitch nose down so aggressively", the co-pilot recounted.

Preliminary information released by Indonesian investigators suggested they were looking at the possible role of the MAX's automated anti-stall technology as a factor in a Lion Air crash in October shortly after take-off from Jakarta.

Data indicated that the pilots struggled with repeated nose-down commands from the plane before it crashed into the Java Sea and killed 189 people.

However, that anti-stall system — known by its acronym MCAS — only activates if the autopilot is turned off, according to documents Boeing has shared with airlines and the FAA. ...

How many threads do you need to start on this?

Get a job and pay some taxes ya dopey bum

Software and reduced pilot input.... pilots no longer know how to fly the aircraft, and often do not fully understand the systems. Back to the stick and rudder, boys, until you learn how to fly.

In ANY crisis, disconnect the auto pilot and fly the aircraft... if you know how.  How many accidents have occurred in recent years from conflicting input from computers and pilots?

I even have an issue with my car computer -  IT decides when it wants to change gears, even though I command it to for a rapid overtake or a hill to climb.. and stuffs up constantly... rather than change gears on command, it 'thinks' about it - that could get you killed when you want sudden power and absolute control to evade a bad situation.