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United 777 "dives" after takeoff from OGG

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United 777 "dives" after takeoff from OGG

Old 12th Feb 2023, 19:08
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Another unreported near-CFIT

UA1722 Maui-SFO 18th December:


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Old 12th Feb 2023, 19:31
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Wow,,,that was close ...

https://theaircurrent.com/aviation-s...22-close-call/
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Old 13th Feb 2023, 07:26
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Dang! It was a Boeing flown by US major with pilots having 25 Khrs combined so we cannot went our very strong feel... I mean: opin... I wanted to say: facts about how Airbus, everyone except the whi... I mean: first world aviators and youn... actually: inexperienced are just a menace to aviation. We can't rant about the weather either, lest we be mistaken as deluded non-thinking fools believing that global warming is real and not just what global conspiracy of lizard-people wants us to believe.

Provided FR24 data are reliable (which they have proven to be more often than not), that must've been a heckuwa rollercoaster ride. Were there any reports of "Scared passenger: we all thought we're gonna die!" in any of the local rags?
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Old 13th Feb 2023, 12:32
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From another website,,

A message from a friend:
Gusty takeoff, heavy rain, heavy plane, short runway, and at night. Used flaps 20.
At accel height, CA (PF) called for flaps 5. FO went through the gate and selected flaps 1. When climb rate dissipated, CA looked over to see the lever and unknowingly banked over as well. CA became disoriented and neither pilot noticed the dive until the GPWS warning. 2.7Gs at 775’ AGL to recover.
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Old 13th Feb 2023, 12:44
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2.7Gs at 775’ AGL to recover.
avorite expletive

At least is was apparently reported to the company
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Old 13th Feb 2023, 15:56
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According to Flight Radar the incident occurred at 1449 local time so daylight and there were no gusts reported in the metar.
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Old 13th Feb 2023, 17:49
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Pilots 'received additional training'.

Ya think? >8000 FPM dive, waited to hear the GPW to recover, within 800' from the water. Finally, advanced technology saves one.
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Old 13th Feb 2023, 19:02
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Originally Posted by Chiefttp
CA looked over to see the lever and unknowingly banked over as well.
There's no appreciable variation in the track during the event, suggesting that there can't have been much in the way of a bank for any length of time.

at 775’ AGL to recover.
The height quoted by FR24 is uncorrected for QNH - the actual minimum height would appear to have been around 150' lower than that.

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Old 13th Feb 2023, 19:44
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2.75g, Jesus Christ, outside of the G Limits for any Passenger Jet and it continued to SFO?
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Old 13th Feb 2023, 19:47
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.. 8000+fpm descend from 2200ft and recover by 800ft..?? Impossible in a B777. . Any pilot could tell that something doesn’t add up here..

Fly safe,
B-757
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Old 13th Feb 2023, 21:32
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Originally Posted by B-757
.. 8000+fpm descend from 2200ft and recover by 800ft..?? Impossible in a B777. . Any pilot could tell that something doesn’t add up here.
Vertical rate (RoD/RoC) is a second-order ADS-B parameter and should be treated with caution in any regime other than a uniform climb/descent.

That said, the elapsed time for the upset from 2200 feet, down to 775 feet and back to 2200 was approximately 28 seconds, so unless doubt is being cast on the instantaneous height values or timestamps, that does indeed appear to be what happened.
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Old 13th Feb 2023, 21:58
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United 777 "dives" after takeoff from OGG

Haven’t seen much about this. United flight 1722 from OGG to SFO experienced a significant drop in altitude after taking off from Maui on December 18. Heavy rain at that time - pilots recovered about 800 feet over the water - then proceeded to SFO. Must have been quite a ride.

More here:

https://theaircurrent.com/aviation-s...22-close-call/


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Old 13th Feb 2023, 22:05
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I was reading the article and was surprised at how reasonable and informed the writing was. Then I saw it was Jon Ostrower; he knows his stuff and doesn't sensationalize.
2.7Gs in a 777 had to be exciting. Weather was bad -- windshear?
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Old 13th Feb 2023, 23:53
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Why wasn't this reported on Dec 18 and why did the crew continue to SFO? What does the NTSB say?
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Old 14th Feb 2023, 03:21
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For those interested, Juan's comments



This comment was posted below the video.

QUOTE:
jdorenbecher

Former pilot and I was on that flight on that day. Shortly after TO the pilot slightly retarded the engines. I noticed it but it was subtle. Then we started sinking. The aircraft did not nose over into a dive. It felt like we were hit with a downdraft. Many screamed and the crew increased thrust and recovered and climbed up to FL39 and smooth air. I normally don't get too bothered by turbulence but I knew we were very close to the water having only been in the air for slightly more than a minute.
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Old 14th Feb 2023, 07:39
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Does Maui have non standard AA? Should be clean well before 2200ft. And selecting flap 1 instead of 5 might not even be noticeable - you’re accelerating anyway. In that weather why not use the autopilot?? Also, not unreasonable to continue the flight to destination. What advantage is there of doing a diversion back to bad weather and maybe even having to dump fuel?
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Old 14th Feb 2023, 08:22
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Originally Posted by Seat4A
For those interested, Juan's comments

https://www.youtube.com/watch?v=1B9mQQnZg_8


This comment was posted below the video.

QUOTE:
jdorenbecher

Former pilot and I was on that flight on that day. Shortly after TO the pilot slightly retarded the engines. I noticed it but it was subtle. Then we started sinking. The aircraft did not nose over into a dive. It felt like we were hit with a downdraft. Many screamed and the crew increased thrust and recovered and climbed up to FL39 and smooth air. I normally don't get too bothered by turbulence but I knew we were very close to the water having only been in the air for slightly more than a minute.
A former pilot but calls it FL39?
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Old 14th Feb 2023, 08:25
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I note that the Jon Ostrower account states that the aircraft arrived in SFO, did a two and a half hour turnaround and then departed to ORD. I have not read the MM for a triple but I would have thought that a 2.7g positive would have required more than a 2.5 hour inspection.

Reminds me of the cartoon of a ground engineer climbing over a farm fence into a field in which two pilots sit amongst a yard sale of smoking aircraft parts and shouts to them, "Don't put it in the book, it's due out in an hour"

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Old 14th Feb 2023, 08:35
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Originally Posted by anxiao
I note that the Jon Ostrower account states that the aircraft arrived in SFO, did a two and a half hour turnaround and then departed to ORD. I have not read the MM for a triple but I would have thought that a 2.7g positive would have required more than a 2.5 hour inspection.
I'd be interested to see the back of the envelope with the "2.7g" calculation, given that we know it didn't come from the FDR.

I'm not saying it's wrong, I'd just like to see the maths.
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Old 14th Feb 2023, 09:12
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Well, the math for the vertical acceleration is simple: -8600 to +8600 fpm (diff = 94 m/s) in (13 s) squared needs appr. 0.6 g, + earth pull makes 1.6 g vertical ballpark. This is of course only a very rough avg. estimate because vert. speeds are secondary data derived from diff between individual ADSB altitude transmissions, therefore peak acceleration could be significantly more.

Last edited by spornrad; 14th Feb 2023 at 09:24.
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