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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

#121

Post by yurishimo »

shdon wrote: post #22
ragebol wrote: post #12

For anyone else (besides me, being Dutch) wondering about the name: https://en.wikipedia.org/wiki/Dutch_roll?useskin=vector#Name TL;DR: it's from ice skating where there's a similar move. But no idea why it's called that in ice skating.

Ice skating... Interesting... My guess was it having to do with ships rocking side to side. Maar waarom een schaatsterm?

At first I read that as `schatsterm` and thought it was cute, but then I looked it up to double check and it's still cool!

But now I know that the word I thought it was is actually a `bijnaam`. Your language is fun and I have been enjoying learning it over the last couple of years. :)

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

#122

Post by FabHK »

exabrial wrote: post #107

What the news about Boeing has done is make me pay more attention to commercial aviation in general. The number of aviation incidents is actually pretty crazy, and no, Boeing is not at the center of them despite what the media would have you believe. What is amazing though is the actual injury and fatality rate is really low due to well trained crews and measured responses by air controllers.

> the actual injury and fatality rate is really low due to well trained crews and measured responses by air controllers.

It’s the crew and ATC staff, definitely, but also

- the amazingly well engineered airplanes (despite recent Boeing hiccups - just goes to demonstrate the high standards) with many redundancies;

- the archaic, but robust ATC system; and

- last but not least the excellent safety culture, which investigates problems thoroughly to the root, but without blaming individuals.

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

#123

Post by agurk »

umvi wrote: post #81
blakesterz wrote: post #4

"Dutch Roll is a coupled out of phase movement of the aircraft as result of weakened directional stability (provided by the vertical tail and rudder), in which the aircraft oscillates around its vertical as well as longitudinal axis (coupled yaw and roll)." That sounds pretty scary. I wonder why it wasn't bigger news when it happened last month?

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_Force_Base_...

[1] - https://theaviationgeekclub.com/the-story-of-bud-holland-the...

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

#124

Post by MeImCounting »

wyldfire wrote: post #113
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…

> 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.

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

#125

Post by matt-attack »

rollulus wrote: post #108

As a Dutchman the endless list of apparent “Dutch” things never ceases to surprise me. Uncles, courage, ovens, double, going, etc., and a new one to my list: rolls. And none of them means any good.

Don’t forget Angles.

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

#127

Post by FabHK »

marcus0x62 wrote: post #24

Years ago, my father in law ( a heavy jet mechanic) got sent to China for two months as part of a team to diagnose and fix a recurring dutch roll complaint on a particular airframe. This was for a A300-series flown by a large freight carrier. The local mechanics couldn’t figure it out, so this team was assembled from the mechanics at headquarters to fix the plane. They inspected the plane and found no damage. They ha…

> they simply did not like this particular plane.

…and employed a face-saving (though probably very expensive) way of communicating it.

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

#128

Post by code_runner »

rollulus wrote: post #108

As a Dutchman the endless list of apparent “Dutch” things never ceases to surprise me. Uncles, courage, ovens, double, going, etc., and a new one to my list: rolls. And none of them means any good.

dutch babies are a pretty decent desert!

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

#129

Post by kleiba »

rollulus wrote: post #108

As a Dutchman the endless list of apparent “Dutch” things never ceases to surprise me. Uncles, courage, ovens, double, going, etc., and a new one to my list: rolls. And none of them means any good.

Half of them refer to "German" things, where the word "deutsch" underwent some pronunciational variation.

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

#130

Post by drstewart »

somenameforme wrote: post #93
bradleyjg wrote: post #53

Earlier quoted context omitted.

Do you think your car (or bike) is safer or more dangerous than the least safe Boeing plane in service?

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…

>The most reasonable way would be safety per average trip

Let's reductio ad absurdum this. I take my 1000CC motorcycle around the block every 10 minutes for a year. Safest transportation mode on the planet! Way safer than walking (which I did once down the middle of a highway, blindfolded)

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