A month ago, we just said about another serious accident with the American Boeing 737 MAX aircraft:
Portland Airport to Alaska Flight 1282 in California, the Boeing 737 MAX climbed to an altitude of 4,500 meters shortly after takeoffThe emergency hatch suddenly fell off and collapsed.
Boeing 737 Max).
Fortunately, there were no passengers sitting next to the collapsed door, and there were no people in the cabin**.
About 40 minutes later, the plane made an emergency landing back at Portland Airport, which was considered a surprise.
The emergency hatch collapsed).
The passengers escaped, but Boeing did.
After all, it was the Boeing 737 MAX that caused the accident....
The Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) quickly launched a comprehensive investigation into the accident, and after more than a month of in-depth investigation, the first report was finally released, and the cause of the accident was once again speechless
There are 4 key bolts on the hatch that I forgot to install....
Screenshot of the investigation report).
How did a large airline, thousands of engineers and maintenance personnel, manage to deliver a 737 MAX without forgetting four bolts?
I'm afraid it starts with the manufacturing and assembly stage...
The 737 MAX is a new aircraft built only last year.
Many of the components are Boeing in the United States and around the worldIt is produced in a subsidiary and then shipped to the United States for assembly
A hatch that collapses is called an in-line typeThe emergency door is manufactured by Spire Aviation Systems Sdn Bhd in MalaysiaThis company is an overseas subsidiary of Boeing.
Aerosystems Aerosystems, Inc.).
The emergency door was produced in May and shipped from Malaysia to Kansas, USA.
On August 31, the emergency doors were transferred to an assembly plant in Renton, Washington, where they were assembled into a complete 737 MAX aircraft with wings, fuselage and other components.
Schematic diagram of the built-in emergency door).
Unexpectedly, on September 1, the emergency door was just installed on the fuselage, and the technician in charge of the inspection found that the rivets of the fuselage were damaged and had to be replaced and repaired.
In order to repair the rivets of the fuselage, the emergency door that had been installed had to be removed.
In this way, the built-in emergency door was dismantled one by one, along with its parts.
Built-in emergency doors and connected parts).
After the crew finished repairing the rivets of the fuselage, they put the emergency door back on.
The problem is that the reinstalled emergency door is missing four bolts
It should be pointed out here that it is not necessarily that the worker forgot to install the bolts back after dismantling the doorIt may also be that when Ruifa came to the United States, he didn't give the bolt at all, but Boeing didn't find out.
The position of the circle is where the bolts are not installed).
And this flaw was investigated after the fact, and found from the technical files and ** data....
Investigators study the emergency door).
In short, in any case, Boeing is definitely responsible, either because he forgot to put the bolts back on, or because he didn't find the inevitable sharp mistake, it's just a matter of which responsibility is heavier.
A few months later, the newly assembled "out of print" 737 MAX was sold to Alaska Airlines.
Originally, when the new plane arrived, Alaska Airlines also had to do a series of inspections, but they didn't find out the problem, and it was put into use smoothly.
On the afternoon of January 5 this year, the 737 MAX took off from Portland Airport and flew to an altitude of 4,500 meters.
The big hole after the emergency door collapsed).
Now, a month has passed since the accident, the preliminary investigation report has finally been released, and we have finally been able to understand part of the reasons and truth behind the "door collapse incident".
However, there are still some problems with this preliminary report – no one is taking the blame.
On Tuesday, the report jointly submitted by the Aviation Administration and the Transportation Safety Committee was sent to the Transportation Committee for questioning. Experts from the Transportation Committee asked a key question on the spot:
When did the 4 missing bolts come from?
Is it the manufacturer that Aeronautical Systems didn't ship to the United States?
Or did the Boeing staff forget about it when they dismantled the door and put it back in order to repair the rivets?
Who is responsible for the "4 missing bolts" is not clearly reflected in the report....
FAA experts are questioned).
Another member of parliament raised other questions:
"Even if you forget to install the bolts, what are the maintenance and overhaul teams doing after the aircraft is delivered? Not a single one noticed that the parts were missing?! ”
In this regard, the Boeing representative at the scene could only answer embarrassedly:
We install emergency doors according to the work specifications....”
Of course, this report is not the final answer, and the investigation is ongoing...
But Boeing's life must be difficult, the 737 MAX was grounded again in the United States, hundreds of routes were affected, and Boeing's stock price also went all the way, and its market value evaporated by nearly 20%.
But compared to the damage caused by the 737 max, it is already a drop in the shadows.
A few years ago, the 737 Max caused two serious accidents that killed more than 300 people, and the aircraft was banned from flying in many countries.
737 MAX to check the emergency door).
In October 2018, a 737 MAX operated by Indonesia's Lion Air Airlines crashed shortly after takeoff, killing all 189 people on board.
In March 2019, another Boeing 737 MAX crashed again shortly after takeoff, leaving no one on board 157 people on board.
After two consecutive accidents, the 737 Max was grounded for 20 months.
Later, Boeing spent billions on the 737 MAX to upgrade the system, and in 2021 paid a settlement of as much as $2.5 billion to the U.S. Department of Justice before regaining flight certification.
But I didn't expect that after two years of re-flying, something happened again...
I hope that the later investigation report can further reveal the full truth of the "door collapse incident", an emergency door, which is related to the lives of hundreds of passengers....