View Single Post
Old 03-15-2019, 03:29 PM
  #53  
km1125
Senior Member
 
Join Date: Feb 2017
Posts: 2,072
Default

Originally Posted by forgot View Post
Attachment 1096928

1 hour ago
Another cut and paste from Zerohedge site. Have not heard some of these thoughts form the Chinese.
Especially no. 3 on redundancy of the sensor.



Following the first crash (October 29, 2018)of Boeing 737-MAX, belonging to Indonesia's Garuda Airline, a Chinese Aeronautical Engineer, at the Chinese National Aeronautic Institute, has wrote a report, on the possible cause of this accident.The report was published on November 27, 2018, one month after the Indonesian crash. The Chinese FAA did not have the gut to ground the Boeing 737-MAX, after the first crash.The Chinese Investigators pinpointed 737-MAX's new stall-prevention MCAS (Maneuvering Characteristics Augmentation System) as the most likely culprit of the crash. This system was designed to monitor the Angle of Attack (AoA), so the plane will not stall, and crash due to lost of lift.And this system will automatically kick in, and will lower the nose of the plane, to prevent stalling of the wing, when certain AoA was exceeded.

Using various reports and Boeing Patent filings of the MCAS, Patent Number: CN106477055A, the Chinese investigators have discovered the following:

1. Boeing did not disclose the newly installed MCAS on the Boeing 737-MAX, to the airlines and pilots, consequently, the pilots don't know about the existence of this system, and therefore, they were not trained on how to handle this system.

2. The MCAS rely on a single AoA sensor, and so there is no logic, to check whether the input from the sensor is correct. This checking of input's correctness requires multiple sensors.

Faulty readings from this single AoA sensor, may be the fatal cause of 737-MAX's crash. 3. Airbus, in contrast, requires their planes, to have 3 separate AoA sensors, and if any one of the sensors do not agree with the others, their stall-prevention system will ignore all of them, and will inform the pilot. 4. The Chinese investigators further discovered that if the pilots intervene, after the MSAC kicked in, by pulling up the plane, the plane will still dive for 10 seconds, and then MSAC will order the plane to dive again, after 5 seconds. 5. The MSAC will only release the control of the plane, only if it thinks, the pilot is nose diving the plane, enough, to prevent the stall. If the Pilot pulls up, the MSAC will regain the control, and order the plane to dive again. 6. Since Boeing did not disclosed the existence of MSAC to the airlines and pilots, the pilots will simply don't know how to turn off the MSAC, even if it could be turned off. 7. Since the Boeing 737 is a 50 years old plane, FAA did not required Boeing to re-certify the plane after the upgrade.

This criminal negligent and collusion between Boeing and FAA has costed over 300 lives, so far.
Boeing has been in the flight and automated flight control business for a long, long time. It would surprise me if the system was so simple that it could be fooled easily and that it wouldn't be easy to override using the basic flight instructions, even if they weren't specific to MCAS. Unless this Chinese guy is a pro at the system and reverse-engineered it completely, it seem quite libelous to make such statements. I'm hoping Boeing has some info that proves this guy wrong and that he's jumping the gun on what really happened to that plane.
km1125 is offline