https://www.dailymail.co.uk/news/article-13053051/Boeing-bolts-missing-max-NTSB-investigation.html
Crucial bolts were MISSING from door plug that blew off Alaska
Airlines Boeing 737 MAX plane mid-flight - in clearest evidence
yet of major manufacturing flaw, damning new report reveals
NTSB report finds four bolts were missing from the door plug
that blew out
It appears Boeing workers forgot to replace them after repair
during assembly
. . .
The critical bolts would have prevented the 'door plug'
from shifting-around vertically. This motion may have
caused fatigue in other door elements.
In any case, this seems to be a FACTORY error - someone
skipped a step and/or inspection. Work might have stretched
over a weekend, with different people involved on Monday.
Other 737s were found to have mis-drilled holes in the
frames.
Can Boeing re-start the 747 assembly line ??? The 737
seems cursed. Now nobody wants to fly on them.