Southwest Airlines Boeing 737 experiences "Dutch roll", lands safely

[thewayne]

No, a Dutch roll isn't a weird sex position. Well, it probably is, but we won't get into that. In an aircraft, it's an uncontrolled side-to-side yawing motion of the tail, and it can be lethal: a 747 experienced that and crashed, killing most all on board. In this case, the plane, less than two years old, experienced it after taking off from Phoenix. The pilots were able to regain control and landed safely. A subsequent investigation found a damaged backup power control unit, which is responsible for power to the tail.

If a Dutch roll is not controlled by the flight crew, it can cause the tail to shear off or otherwise fail catastrophically.

The plane was grounded for several days and then flown to Everett, Washington where one of the airline's major maintenance vendors is located. Reportedly no one was seriously injured in the incident, though many were violently ill.

https://www.npr.org/2024/06/13/nx-s1-5004725/boeing-737-max-southwest-dutch-roll

https://news.slashdot.org/story/24/06/14/0331240/faa-is-investigating-new-incident-involving-a-boeing-737-max-8-jet-in-midair

Comments

[acelightning73]

I saw a crash investigation video about a plane that went into a Dutch roll because the dashpot screw that moves the vertical fin had come unscrewed because a stop nut had come off. The rudder was just flapping in the wind.

And what the hell is the nonsense about FAKE TITANIUM?

[thewayne]

I just saw an article on fake titanium, haven't read about it yet.  That is scary in the extreme!

[acelightning73]

That sounds like the old joke that the sheet metal of the fenders on certain cars was made from aluminum foil gum wrappers. Titanium is an element, with specific measurable properties. Or has someone turned lead into gold, but it turned back?

[thewayne]

Or sending an alloy with less than the specified amount of titanium present?

[acelightning73]

I would think they'd have quality-control testing at several stages of the supply chain.

[thewayne]

According to the HuffPo article, there was substandard material and corrosion noted.

[disneydream06]

Scary thoughts. :o
Hugs, Jon

[kaishin108]

I read that the Dutch Roll is an ice-skating term where they roll from side to side. ;-)

This all just sickens me. Boeing, pfft.

[acelightning73]

Has anybody ever heard of QUality Control? When I worked at Grumman, there were signs all around the plant saying "ZERO Defects!"

[silveradept]

Woof. The problems continue for Boeing. That Dutch roll sounds like something that could be very dangerous.