United Airlines 777 dives after departure | Hacker News Reader

United Airlines 777 dives after departure

flightradar24.com

74 pointsmji49 comments

This article [1] notes that "The incident, ...came the same day 25 people were injured, six seriously, aboard a Hawaiian Airlines flight from Phoenix to Honolulu during severe turbulence in the vicinity of Maui."

A local source [2] comments on the weather that day: "On the day this happened, we recall well that the Hawaiian Islands were in the midst of an exceptionally strong wind and rainstorm that was, even for Hawaii, highly unusual."

Correlation, not causation, but a speculative explanation nonetheless?

[1] https://theaircurrent.com/aviation-safety/united-maui-dive-u...

archive: https://archive.is/RonQy

[2] https://beatofhawaii.com/bad-timing-weather-warnings-hawaiia...

archive: https://archive.is/Fd0C4

Is there an uptick in aviation-related near-incidents lately? Difficult to tell if it’s real, coincidence, or just HN has developed an interest lately.

I'm not a domain expert but a perusal of https://avherald.com/ might indicate if there is an uptick or not.

I think Simon is rate limited, and posts as much as he can from a much larger sample size. So probably not useful in terms of identifying frequency trends.

Something very similar happened to a Qatar Airways flight a few days ago, coming as low as 800 feet from the ocean. Scary stuff.

First time seeing this one. Indeed, quite scary:

> FlightRadar24 tracking data shows that, after taking off at 2am, the Qatar Boeing 787 started losing altitude only a minute later, when the plane was at 1,850ft.

> The aircraft then suddenly dropped 1,000ft in 24 seconds.

https://www.independent.co.uk/travel/news-and-advice/qatar-p...

That's wild, per the article the first officer was flying and simply got disoriented. Aircraft was recovered by the captain. That's the sort of thing you would expect to happen to a newly-minted private pilot in a cesna, not a commercial pilot in a fully-loaded 787!

My own airline had an incident recently where one of our senior captains became so disoriented taking off at night over water that he thought every flight instrument onboard had become unreliable (VERY unlikely). He dove toward the ground but fortunately managed to land before a disaster occurred. His First Officer stated that she knew the problem wasn’t the flight instruments, but didn’t correct the captain adequately.

You’re right, these experienced pilots should know better, but incidents do happen.

What is inconceivable, even for layperson, is that when in doubt you should always gain altitude, not lose altitude.

In addition to what huslage said, there’s something called an aerodynamic stall: in very oversimplified terms, if you go up too steeply without adequate thrust your wings will produce dramatically less lift all at once.

Or even worse, and more likely, just one one side (wing drop). Then you're really doomed. Happened recently on an ATR I think.

I did some flying with a hood - no ability to see outside but I could see instruments. It was uncanny, and I got totally disoriented.

The only thing that saved me is that as a former sim jockey I was used to flying just on the instruments and I knew it was very unlikely that they went wrong just as I was flying blind. So I focussed on the instruments and ignored the feeling that the plane was literally flying on its side.

It is very unsettling.

If you don't know you're going down, you might think you are upside down and going up. Disorientation is a strange thing.

Interesting, link:

https://onemileatatime.com/news/qatar-airways-pilot-loses-si...

I've been wondering the same thing. Could it be the FAA really dropping the ball or the airlines are struggling to manage?

My theory is pilots and maintenance crews are stretched way too thin after the pandemic layoffs and subsequent post covid boom. Therefore, more mistakes are happening.

I have no data to confirm, but as a relative of a pilot, they are reporting taking a lot of "green slips" (uncovered flights) and experiencing some pressure to come in while fatigued, which they are resisting successfully as they have enough seniority and $ to not make it worth it.

Wonder whether a corollary of that would be that more inexperienced pilots are succumbing to the pressure and coming in while fatigued.

Juan Brown of the blancoliro channel on youtube had been talking about this near the beginning of the pandemic. The flying industry came in and asked for a large number of long time pilots to early retire at the start of the pandemic, and I believe a large number did. Then somewhat quickly demand bounced back causing a pilot shortage, leading to the industry putting out a call for new pilots.

https://simpleflying.com/southwest-airlines-lowers-minimum-h...

> Effective February 7th, aspiring Southwest pilots will need at least 500 flying hours on jets or turboprop aircraft, down from the 1,000 the airline currently requires. The Dallas-based budget airline communicated the change in an internal memo addressed to pilots and later explained that the rationale behind this decision is the willingness to increase opportunities for an airline pilot career to more skilled pilots.

https://www.cbsnews.com/news/why-is-there-a-pilot-shortage-c...

> And the military itself doesn't have enough pilots — a Department of Defense report from 2019 says the Air Force has seen shortfalls since 2006, and the service said it was short more than 1,500 pilots at the end of 2016 — "with the deficit expected to grow." By the end of the 2019 fiscal year, it had — to a deficit of 2,100 pilots, according to written testimony submitted to Congress in 2020.

> The military has also struggled for years to meet its own goals for training new pilots.

TLDR There is a pilot shortage. Lots of pilots retired or took buyouts during COVID when air traffic plummeted, and the pipeline is insufficient to meet the demand ramp.

Additional citations:

https://doav.virginia.gov/calendar-and-news/news/2020-june/s...

https://www.cnbc.com/2022/05/15/us-pilot-shortage-forces-air...

I'm not surprised. Getting a pilots license is an expensive endeavor. Then it's lots of years flying in backwoods places for low pay.

From my pal, a 777 United Pilot...

"I was actually flying Hawaii the day after….

I remember because it was the worst turbulence I’d every experienced on that route!

Caused by a massive weather system that hung-out close to hawaii for a number of days while it slowly moved northeast toward the west coast of the CONUS…

So repeating storms: small but ferocious! Heavy rain with gale force winds forcing closure of the airports several times during this period…"

And: https://twitter.com/nwscwsuzoa/status/1605045345691373568?s=...

> The incident was first reported by The Air Current, which analyzed granular data supplied by Flightradar24... UA1722 took off at 00:49.28.882 UTC on 19 December (14:49 local time 18 Dec). It climbed to a maximum altitude of 2,200 feet at 00:50:39.007 before descending to 775 feet at 00:50:57.500. The aircraft recovered from its dive and resumed its climb and safely arrived in San Francisco at 05:03 UTC.

God, what a beautiful world we live in. Even in the event of a catastrophic aircraft failure, rest assured that millisecond-granularity data of your last moments will be recorded, as you plunge into the sea.

Wouldn't want it any other way.

Edit: Wow, I guess a lot of people disagree with this or think I'm being sarcastic. I'm not: I honestly think aviation telemetry is cool, and I left this comment expressing that if I was involved in a crash or near-crash (such as the one we're all discussing), I would think it's cool that the exact flight trajectory was recorded in such detail.

> Even in the event of a catastrophic aircraft failure, rest assured that millisecond-granularity data of your last moments will be recorded, as you plunge into the sea.

If you're close enough to shore that an ADS-B receiver can record your planes' transmissions.

Post MH370, ADS-B data is relayed by Iridium satellites:

> Aireon has deployed a space-based air traffic surveillance system for Automatic Dependent Surveillance-Broadcast (ADS-B) equipped aircraft throughout the entire globe. Aireon is harnessing next-generation aviation surveillance technologies that were formerly ground-based and, for the first time ever, is extending their reach globally to significantly improve efficiency, enhance safety, reduce emissions, and provide cost savings benefits to all stakeholders. Space-based ADS-B surveillance covers oceanic, polar, and remote regions

Very true, although latency is much greater, so you may not get the last (hundreds of) milliseconds, as you would with ground-based receivers.

Why not? That data would still be transmitted, it would just take a little longer to receive..

Yes, excellent point. For some reason, I had in my head that an ack was necessary.

I guess the positive takeaway is that every death makes aviation safer for the future because we almost always learn from the data.

FWIW commercial aviation is already far safer than driving and the telemetry allows us to call out incidents like this and get to the bottom of what happened.

I have experienced a dive like this on a flight before. The airplane had some kind of pressure failure so the pilot intentionally dove from about 10k feet to 1k feet in 30 seconds or something crazy. Extremely scary, nothing communicated over the intercom to us until we were in a fully banked 180 degree turn heading back to the airport. Honesty surprised this didn't go viral on tiktok.

Are you sure you are not recollecting the altitudes or the cause of the dive incorrectly? Depressurisation at ~10 000 feet does not really grant an emergency dive; in fact emergency dives for depressurisation usually end somewhere slightly below 10 000 ft, which is very much in the breathable zone. Furthermore, pressurised aircraft usually have an equivalent pressure (cabin altitude) of ~6-8 000 ft, which is not too far away.

I do not now re: FAA, but EASA regulations permit flight in unpressurised aircraft between 10 to 13 000 ft without onboard oxygen for 30 minutes. Onboard oxygen is required beyond 30 minutes if > 10 000 ft and < 13 000 ft or immediately if > 13 000 ft.

> Extremely scary, nothing communicated over the intercom to us until we were in a fully banked 180 degree turn heading back to the airport.

I can understand that. The primary task of the pilots is to fly the airplane, and I would think they had their hands full doing that.

in that order: "aviate, navigate, communicate"

Shit that must have been scary!

With the OP plane, it carried on going, so it couldn't have been pressure I reckon (not an expert).

Ok people you want to know the truth. I know I am going to take flack for this. Truth. The airlines are hiring pilots that are not experienced. 1500 hours is the minimum. When I had 1500 hours. I didn’t know shit. Many of these young pilots don’t have basic flying skills. They will take any short cut to get to the airlines. Of there is a hard way and a easy way. They will take the easy way every time. Especially if there is an APP to go with it. If you ask a new hire. They are GODs gift to the airlines. Management is just filling seats. HR is in charge of hiring pilots. Pilots are now out of the hiring loop. HR is just filling quotas. The airlines are now scrapping the bottom of the barrel. More accidents will come and happen. Many of the newer pilots have no LOVE for aviation. The older pilots did. The newer pilots just money and good days off. 1500 hour pilots don’t know what they don’t know. I hate to say this. Not everyone can or are made to fly an airliner. Just like I can’t don’t Calculus or Trig. Signed Captain X (Retired) Third Generation Airline

That may be true, but these two pilots had 25000 hours between them.

I have experienced a dive like this (EasyJet Geneva-Copenhagen, 2013). It was really scary, to say the least. But apparently this is a relatively common situation, and aircrafts are sturdy enough to handle this without any problems.

(Also, one of the reasons to fit your seat belt correctly).

I don't think the scary part was the dive by itself, but how close it was to hit the ground/sea. Don't think planes are sturdy enough to handle that :D

I don’t think it’s “common” and certainly it’s not normal.

It's not necessarily about the plane structurally handling it, but that if it occurs shortly after takeoff, there isn't much altitude to pull out of a steep dive before crashing.

The salient point of this post is how close the plane came (withing a few hundred feet) of impacting the ground.

> It climbed to a maximum altitude of 2,200 feet at 00:50:39.007 before descending to 775 feet at 00:50:57.500.

ONE more second and everyone on that flight would have been done.

Pilots need to get paid more.

They kept flying for 5 hours afterwards, which means the CVR will not have record of this incident (unless they pulled the circuit breaker soon afterwards, which is unlikely).

Admiral Cloudberg et al. have spoiled me; this info is boring without analysis.

That is true! I mentally calculated the feet per minute and compared it to some from crashes mentioned by him. About 1500 ft in 20s is 4500 ft/m so pretty steep but his reports I am sure have gone up to the 10000s.

I am interested in: did they stall? I guess FR had speed data so you could guess. Did they land at the destination or do an emergency landing somewhere?

There’s a chart of the speed - it’s around 250 knots so they’re going fast enough (source: personal MS flight simulator experience). The angle of attack is not shown, I think.

I am super curious about this: big dive, probably not a stall (?) but either aircraft was airworth to carry on to destination OR at least the crew thought it was. So all the controls and systems should be working properly, engines working. I am guessing they saw something worth avoiding? Birds? UFO (literally ... not aliens)? Another plane?

The linked article says they landed at destination.

Boeing software problem?

Ha, it's a good question.

I went to YouTube (as I follow a couple of incident analysis-giving pilots, "MentourPilot" and "74 Gear").

Anyway, there were interesting reports from a couple of Emirates 777 flights which appear to have the same issue [[1], [2], pilots zero-ing altitude on autopilot control {MCP}], but it doesn't look like the OP's issue; it's low-trajectory, not diving.

There was also a stall on take off [3] which might correlate with the issue here?? Also, of course, there's compressor stalls which I gather are usually bird strikes?

Certainly not enough information to make any judgement on cause. No doubt there will be reports out in due time.

[1] https://www.youtube.com/watch?v=F7Mbw0vVcS0

[2] https://www.youtube.com/watch?v=23fiDj8Uy6Q

[3] https://www.youtube.com/watch?v=SO3xmzoLzfI

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