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Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

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Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#181

Post by Out_of_Characte »

geekfactor wrote: post #109

I didn't know what it was called, but I've experienced mild Dutch Roll enough on flights, usually on the approach or landing, that I didn't realize that it was all that rare or dangerous. I had come to think of it as a normal result of wind shear. I imagine it's a matter of degree, and I wish there was some mention of the magnitude of the Dutch Roll in this case vs what is considered normal or acceptable. (Edited to…

How did you tell the difference between dutch roll and the plane catching a glideslope?

Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#182

Post by sjm-lbm »

nabla9 wrote: post #139
senordevnyc wrote: post #52

Earlier quoted context omitted.

While true, this was a pretty different situation in that it was 1959 (engineering standards have changed a lot in the last 65 years), and the dutch rolls were being performed intentionally for demonstration purposes.

1985 the dedliest single aircraft accident was due to dutch roll. Japan Airlines Boeing 747SR. 2013 KC-135 Stratotanker broke up in flight due to dutch roll. 2005 Airbus A310 survived with serious structural damage.

> 1985 the dedliest single aircraft accident was due to dutch roll. Japan Airlines Boeing 747SR.

This kind of buries the lede, right? A bad repair caused an explosion that blew off most of the vertical stabilizer (ie, the tail). The dutch roll was part of the series of unfortunate events that followed.

Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#183

Post by epolanski »

throwup238 wrote: post #78
epolanski wrote: post #39

Earlier quoted context omitted.

1) Even if the max had hiccups, plenty of them, it is an absolutely safe airplane by any measure. 2) Your fleet may mostly be formed by Boeing airplanes, having all of those move to Airbus airplanes is also a safety issue. Pilots have to re-learn and even forget things they accrued and evolved to react instantly for decades. At some point you need to weigh the odds of increasing human error vs relatively safer Airbus…

> 1) Even if the max had hiccups, plenty of them, it is an absolutely safe airplane by any measure. Except fatalities.

Even by fatalities.

737 Maxes have flown more than a couple of million of flights, at least, since they entered service, that puts their fatal incident rate at similar levels of the A320.

The only two incidents, also, as you know, were related and both happened 5+ years ago.

Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#184

Post by DiggyJohnson »

FrustratedMonky wrote: post #35
kcplate wrote: post #27

Earlier quoted context omitted.

I guess it’s worse than it looks? The video was kind of a dramatic let down to be honest. I preferred the mystery.

Yeah, could this be caused by turbulence? Winds? Looking at the video, now i'm not sure I haven't been through some dutch rolls also.

For what its worth, that's very unlikely in the last decade or so. More likely to be moderate turbulence, which would be nearly indistinguishable in a non-severe event.

Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#185

Post by fred_is_fred »

dotancohen wrote: post #159
Filligree wrote: post #2

This just isn’t Boeing’s decade.

Until the McDonnell Douglas management retires, Boeing will not recover. It's not a matter of an unlucky decade, it's a matter of replacing engineering with MBAing. It's just that the latency between cause and effect are long on the engineering side of this industry.

The merger was 27 years ago. While it may have been the cause at the time, there’s no more McD to blame. Anyone who was a senior leader in 1997 has long since retired. This is Boeing and only Boeing’s problem.

Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#186

Post by kqr »

MeImCounting wrote: post #124
wyldfire wrote: post #113

Earlier quoted context omitted.

> barrel rolls are generally safe even for large planes since it's a stable 1G maneuver Maybe "safe" here means that merely the stress of the maneuver itself wouldn't destroy the craft? But surely the loss of lift is likely to put it at significant risk, as in your example.

You dont lose lift in a barrel roll, you merely change the direction that lift is being generated.

When the threat is the ground, maybe that's what's worrying anyway.

Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#188

Post by FrustratedMonky »

dboreham wrote: post #112
salawat wrote: post #57

Earlier quoted context omitted.

>The pesky customers want "Safety", and we aren't selling "Safety", got to get some of this "Safety". Guess we better do some re-orgs, some focus groups, some training to make sure everyone knows "Safety" is important. Maybe throw in some training on "Quality". Gah hahahaha. Oh God, don't make me laugh that hard. One does not merely add some more Quality to a product as if it were flour in a cooking recipe. Quality i…

It all starts when psychopaths on wall st install psychopaths in the C suite.

Not even hiding it.

https://www.forbes.com/sites/jackmccullough/2019/12/09/the-p...

Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#189

Post by somenameforme »

krisoft wrote: post #110
somenameforme wrote: post #93

Earlier quoted context omitted.

These numbers are always pretty BSy because the big dangers in flight are take-off and landing. Comparing distances just completely obfuscates everything for no real gain. You can illustrate this clearly with some sort of reductio ad absurdum. Imagine we have an interstellar ship traveling many trillions of miles, but that blows up 90% of the time. If you look at it in terms of this same deaths/mile metric it'd still…

Okay. So let's compare accidents per flights to accidents per trip with bike/car. IATA reports 1.19 accidents per million flights in the 2019-2023 years. [1] Your turn to find a comparable number for road vehicles. 1: https://www.iata.org/en/pressroom/2024-releases/2024-02-28-0...

You pretty quickly shifted the goal posts there didn't you? That's for all flight vessels, not just Boeing's 737 class. You're also misreading your stats (that's per sector, not per million), but in either case I'm more interested in fatality rates. Your site gives a hull loss rate of 1 per 4.94 million flights for jets. For vehicles, the average person makes two trips a day over a total of 29.2 miles. [1] So we can say the average trip is 14.6 miles. And the average fatality rate is 1.33 per 100 million miles traveled [2]. So that's 1.33 fatalities per (100 / 14.6) = 6.8 million trips, or 1 fatality per 5.17 million trips.

So on a first level analysis, vehicles are slightly safer than jets on a trip for trip basis. But the math I'm doing dramatically understates the actual difference, because the mortality numbers I'm using for vehicles are per person, not per fatal incident. In other words 1 PERSON dies per 5.17 million vehicle trips. And I'm comparing that against one entire JET 'dying' per 4.94 million flights, which is generally going to have tens to hundreds of people on it. If you do an apples to apples comparison, vehicles would be some orders of magnitude safer than jets, trip for trip.

Of course ideal would be to ignore population and just look at car incidents with at least 1 fatality vs plane incidents with at least 1 fatality, but I can't find those stats unfortunately.

[1] - https://newsroom.aaa.com/2015/04/new-study-reveals-much-moto...

[2] - https://www.iihs.org/topics/fatality-statistics/detail/state...

Re: Southwest Airlines Boeing 737-8 Max Experienced Dutch Roll

#190

Post by chipdart »

agurk wrote: post #123
umvi wrote: post #81

Earlier quoted context omitted.

Not as scary as flying upside down which is what I originally thought based on title alone. Most people are familiar with "barrel roll" but by comparison this just looks like wiggling. Counterintuitively though my understanding is that barrel rolls are generally safe even for large planes since it's a stable 1G maneuver (some jock irresponsible air force pilot used to regularly barrel roll B-52s until he did one too…

I'm not aware of a B-52 being crashed in a barrel roll, but this did make me think of the 1994 Fairchild crash[0] that was caused by a pilot who was known as dangerous due to excessive self confidence. In this case he banked too tightly at low level causing a stall into the ground. The whole crash was caught on camera[1], which is indelibly burnt into my memory. [0] - https://en.wikipedia.org/wiki/1994_Fairchild_Air_…

Dutch roll, Bud Holland... Netherlands trifecta is in play.
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