6/1 NH171 "Critical" Incident: Cabin Pressure System Malfunction
 

https://headlines.yahoo.co.jp/hl?a=2...002-awire-soci

On June 1st, NH 171, departing San Jose for Tokyo Narita, encountered multiple system failures including cabin pressurization loss, which prompted to the B787-8 to quickly descend from cruising altitude at 43,000 ft to 10,000 ft within 10 minutes. Cabin pressure stabilized and flight resumed normal operations once all systems recovered. Oxygen masks were not deployed and there were no injuries reported. Scary in light of recent Boeing issues.

I've yet to find an English version and this incident is currently under investigation by JCAB, the NTSB equivalent in Japan. JCAB has ruled this incident as "critical". ANA experienced a similar cabin pressurization malfunction back in 5/27/2016 on NH561 from Tokyo Haneda to Kochi (B737-8, domestic).

What other systems failed? The video only mention cabin pressure.

Loss of cabin pressure is not an uncommon event, and if the oxygen masks did not deploy, the actual loss of pressure while at cruising altitude and during the rapid decent must have been limited.
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What recent related critical Boeing events have there been that should make this extra worrisome?

The article mentions other systems (primary and secondary, vague), implied that it's related to the cabin pressure loss, failed or stopped. Perhaps someone with technical knowledge of aircraft parts in Japanese can chime in.

Regardless of whether loss of cabin pressure is a common occurrence or not, the JCAB ruled the incident as "critical." If I'm not mistaken, is it not uncommon, or to make it less confusing with double-negatives, is it common for governing bodies like the JCAB, NTSB, etc. to rule incidents as "critical"? Gosh, if so, that's something I didn't want to be aware of. Hopefully, the investigation concludes this was one of those common occurrences you mention, not something that could have led to a disaster.

Boeing's certification process has been under scrutiny after the MAX debacle. CFO revealed at UBS conference earlier today that Co is still facing questions from global regulators on MAX. The FAA issued an airworthiness directive on wheels and braking systems on less than a hundred 787-8 and 787-9's. In mid-May during 1x1 meetings at HQ, Mgmt gave perspective on the Lion Air and Ethiopian Air crashes - they said the crashes occurred due to failures in a long chain of events. Pointing to history, they said it's rare for a singular event to lead to a catastrophic end to a commercial jet.

Not fear-mongering, just stating facts, and more since you asked. Given how safe commercial aviation is, ANA's B787 incident likely a non-issue. And in light of controversies surrounding Boeing as of late, regulators likely being more prudent than usual, and they should.

It's more critical than someone throwing a bread roll at an FA, or a catering truck scratching a plane's fuselage on the ground, it may be an indication of how they prioritize the investigation into this rather than severity.

The article that two systems that control the cabin pressure failed, and an alert was shown in the cockpit, they reduced altitude to 10,000 feet. After the descend the 3rd and final system failed, but as they were now at lower altitude, the cabin pressure did not go low enough for the oxygen masks to be released. The plane continued to Tokyo, and landed 12 minutes early. Last a similar thing happened to ANA, double system failure for cabin pressure, was in 2016 on a domestic 737.

I missed the article link in first reading, somehow assuming it was the YouTube link written out.

So, only the cabin pressure systems failed. No other systems. It is bad enough though that all three systems can fail at the same time. I do believe this is a serious incident, and should be investigated. It is an interesting case, and I am curious to know what caused all three systems to fail.

Linking it to the 737MAX issues is in my opinion somewhat of a far fetched point. I did not want to write the f-m term, and I did not. But it was on my mind. All that being said, I do appreciate you taking the time to post the link. I would not have seen the story if not. :)

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