12 ms·
United flight from Hawaii plunged to within 800ft of Pacific Ocean
- sposeray 4y ago[dead]
- bombcar 4y agoThe verbs here are a bit alarmist - descended from 2200 to 800 feet over 45 seconds sounds less horrible - though this should have been reported even if just to NASA.
- blessedwhiskers 4y ago"Flight tracking data analysis revealed that the Boeing 777-200 had reached an altitude of roughly 2,200ft when it began a steep dive, descending at a rate of about 8,600ft a minute" The article additionally says the entire ordeal lasted 45 seconds, but clearly part of that 45 seconds was a steep dive.
- netsharc 4y ago2200-775 = 1425ft total dive. At a rate of 8600ft/min, they were in a dive for about 10 seconds. But obviously levelling off means a rate of dive a lot less than 8600ft/min.
- LeFantome 4y agoYa, at the rate described, it would have been more like 10 seconds of dive. Pretty scary if you are looking out the window I imagine. I mean, at the rate given, they were about 5 seconds from the water. I think that would have felt plenty dramatic to me.
- pdx_flyer 4y agoI would assume that situational awareness for those inside the plane would have actually been pretty poor. They were climbing through clouds when the dive began so seeing the orientation of the plane to the earth would have been very spotty.
- cactacea 4y agoAs a passenger, even if I couldn't see out the window, you'd definitely know you weren't going "up" anymore at that rate of decent. Combined with "we just took off" I'm certain that at least a few people in the cabin knew something really bad might have been about to happen.
- inferiorhuman 4y agoAs a passenger, even if I couldn't see out the window, you'd definitely know you weren't going "up" anymore at that rate of decent. No, you really wouldn't. Even for the pilots spatial disorientation is a real problem and they have instruments to show which end is up.
- runnerup 4y agoI follow most of my flights (especially takeoff/landing) with all the sensors in my smartphone. In flights without emergency events, the most useful for me is barometric pressure. When they suddenly drop the pressure by 20+% after achieving cruising altitude, half the plane shortly goes to sleep. I presume due to the lower partial pressure of oxygen.
- inferiorhuman 4y agoSure, but then you're talking 10,000 ft or more. The pressure differential between 2,200 ft and 775 ft is much smaller. It's possible some folks' ears popped, but IMO unlikely that they would've attributed it to a steep descent. Instead I'd expect folks chalked it up to the cabin pressurizing if they even noticed. If passengers noticed and thought there was something wrong this would've made news much sooner. I presume due to the lower partial pressure of oxygen. Probably the lower oxygen content. My pilot friend claimed to have raised the cabin altitude a smidge back in the DC-10 days if FAs complained about e.g. noisy babies. I assume he's full of shit, but you never know.
- runnerup 4y ago
- inferiorhuman 4y agoThe verbs here are a bit alarmist Nah, they're appropriate. Getting that low (less than 775 ft) is bad, doing that on climb out is worse. There's no margin for error at that height. Moreover the plane pulled 2.7G which is in excess of what the plane is rated for (2.5G). The pilots should've returned (to Maui or the Big Island) for an inspection instead of continuing on with the flight. though this should have been reported even if just to NASA. What I've read is that the incident was reported after the flight landed at SFO.
- mdmglr 4y agoWhat would NASA do with this information? Do they have an aviation incident response I’m not familiar with?
- sveiss 4y agoYes, they operate the Aviation Safety Reporting System[1] in the US. It’s intentionally kept separate from the FAA, which has the enforcement role, to encourage reporters to come forward. The second ‘A’ in NASA is ‘Aeronautics’, after all, so it’s a reasonable place to put this function. Reporting to ASRS comes with a certain degree of immunity to enforcement actions, and keeping it separate from the FAA reinforces that. They have a monthly publication, Callback, which includes anonymised snippets of reports, with each issue presenting lessons learned and usually centred around a specific theme. It’s worth a look if you have an interest in how the US aviation system tries to prioritise safety. [1] https://asrs.arc.nasa.gov/ https://asrs.arc.nasa.gov/
- pdx_flyer 4y agoOriginally reported by The Air Current here - https://theaircurrent.com/aviation-safety/united-maui-dive-ua1722-close-call/ https://theaircurrent.com/aviation-safety/united-maui-dive-u... "The aircraft quickly recovered, but not before descending below 775 feet. Two people familiar with the incident said the climb produced forces of nearly 2.7 times the force of gravity on the aircraft and its occupants as that steep descent transitioned to an 8,600 foot per minute climb. The entire incident appears to have stretched no more than 45 seconds and in between radio calls with air traffic controllers in Maui, according to LiveATC recordings reviewed by The Air Current" Later on in the article it states that no mention of the incident was made to Air Traffic Control and the flight continued on as normal.
- etempleton 4y agoA bit concerned that all of the layoffs, forced retirements, and cost reductions in the airline industry have reduced the safety of commercial flights. There have been so many near incidents lately and they have all been unforced errors either by pilots or air traffic controllers who are either undertrained or overworked. It seems especially crazy today where one could imagine much of the process could be heavily assisted by computers if the investment were to be made.
- SQueeeeeL 4y ago'Luckily, no accidents have happened yet, so we still have nothing to worry about' -The US Govt
- rolenthedeep 4y ago'oh, no, those accidents don't count'
- cinntaile 4y agoHave they really? Or have airline near-crash stories for some reason been more popular on HN lately?
- bmitc 4y agoThe article itself mentions all the recent events.
- bmitc 4y agoIt's also disturbing that this wasn't self-reported. It isn't clear from the article what triggered the investigation. It isn't even clear why this happened or why the plane entered into such a steep ascent afterward or why the flight wasn't canceled.
- deleted 4y ago[deleted]
- 4y ago
- kej 4y agoBetween the passengers and the people who monitor aviation radio data, I'm surprised this story didn't come out sooner.
- throwawayx134ax 4y agoCould have been really crappy weather and a very turbulent flight. I'm not sure I would be able to tell the difference between 2.5g and some of the severe jolts I've been in.
- throwawayx134ax 4y agoHuh, given the steep dive, and equivalently steep climb-out, I wonder if they got hit by a microburst?
- bombcar 4y agoExactly - do we have confirmation it was actually a dive and not a downdraft/updraft? Because flying into a sudden downdraft would barely be noticeable by anyone who wasn't looking at instruments (you can still be climbing in air that is descending).
- kioleanu 4y agoThis is eerily similar with this recent incident: https://avherald.com/h?article=504d75c7&opt=0 https://avherald.com/h?article=504d75c7&opt=0 In the Qatar case, they mentioned that the pilot insisted on manually taking off and lost his bearing. The conditions look similar here and I wonder if it’s the same story.
- mzs 4y agoprobably not: https://news.ycombinator.com/item?id=34766838 https://news.ycombinator.com/item?id=34766838
- egberts1 4y agoI am surprised that the plane did not return back to its departure due to having exceeded manufacturing spec for maximum 2.3 G force to inspect for cracks in wings and fuselage. Hopefully, that plane will be taken out of service in SFO.
- inferiorhuman 4y agoHopefully, that plane will be taken out of service in SFO. Ron Howard as the narrator: it wasn't. Edit: The article I read said it was not. Actually, I don't see anything on the Guardian's article indicating any inspection was performed. https://theaircurrent.com/aviation-safety/united-maui-dive-ua1722-close-call/ https://theaircurrent.com/aviation-safety/united-maui-dive-u... The Boeing widebody … was quickly turned around at SFO and departed to Chicago on its next flight about two and a half hours later.
- throwawayx134ax 4y agoThe article said it was inspected on landing at SFO.
- egberts1 4y agoso United wanted the full(er) inspection to be done at United O'Hare Maintenance Facility, got it.
- inferiorhuman 4y agoso United wanted the full(er) inspection to be done at United O'Hare Maintenance Facility, got it. No. United has a massive maintenance base at SFO and this sort of inspection is important enough that you wouldn't put a plane back in revenue service without conducting a check.
- egberts1 4y agoCOO Toby Enqkvist is stationed in Chicago. And only the most rigorous inspections are done in O'Hare facility where all the best equipments are and under watchful eyes of executives. This is expected given how many times FAA has hit United Airline in last 12 months for not doing safety inspection. So I am guessing it went to ORD.
- empressplay 4y agoI fly back and forth from Australia fairly often and it always gets bumpy south of Hawaii -- the worst was a thousand-foot drop that threw people around the cabin. I always keep my seatbelt on when transiting that area!
- Havoc 4y agoUS seems to be having more aircraft drama than usual lately, no?