Originally Posted by
gums
The air data sensors appear to be just behind the radome and access panels for the radar. There's possibility of contamination or even a "loose" pnematic line depending upon the actual configuration of the air data sensors.
Yes - specifically the LH ADM needs to have the pitot input disconnected to gain access to the radar.
GOL nearly lost a B738 seven years ago. Fresh from the factory, a radar failure required a software reload. When the technician reconnected the pitot hose, the connector was engaged, but not twisted in the bayonet fitting to lock it. The result was intermittent UAS, with vertical excursions even more extreme than the Lion Air.
That the crew and pax survived to tell the tale was, according to the report, largely due to a deadheading captain on the jumpseat who exhorted the PF (and the check captain in the RH seat) to "fly the d*mn airplane" (or words to that effect in Portuguese).