Watch how this ship flexes

[David M]

This is actually quite normal. Without flexing it would crack.

https://www.youtube.com/watch?v=PmlTk_3NN_g

[Vasco]

Reminds me of the old Liberty ships. (WWII tonnage). They say that a wag painted a dotted line just forward of the midships accommodation (aft of #3 hatch) with "tear on dotted line" near it.

[blazeit420]

Originally Posted by David M

This is actually quite normal. Without flexing it would crack.

that's crazy, two words, metal and fatigue .

[Sailmonkey]

Originally Posted by blazeit420

that's crazy, two words, metal and fatigue .

Two words

Design life


Sent from my iPhone using Cruisers Sailing Forum

[MarkJ]

Found this one while watching the other.

At 6 minutes see the inside of the cruise ship. And at 9 minutes the cars on the ferry deck.

https://m.youtube.com/watch?v=qHzvTSac1Q4

[ontherocks83]

Very cool

If you really want to freak someone out show them how much a airplane wing or helicopter blade flexes when in flight. You need a slow motion camera to capture it but it freaks people out and has a tendency to make them not want to fly.

[Steadman Uhlich]

And I thought only MacGregor 65s and other ULDBs did that!

Flexibility is something I appreciate more as I get older. But in boats, it is a balancing act of stiffness and flexibility.

Cool video.

[Dennis.G]

Originally Posted by ontherocks83

Very cool

If you really want to freak someone out show them how much a airplane wing or helicopter blade flexes when in flight. You need a slow motion camera to capture it but it freaks people out and has a tendency to make them not want to fly.

[Steadman Uhlich]

Originally Posted by Dennis.G

WOW!

That is amazing!

[crazyoldboatguy]

Trees flex in the wind and we think nothing of it.

There are many DC3s left flying in the world and they have been flexing for 70 years.

[NOLA_sailing]

Originally Posted by ontherocks83

Very cool

If you really want to freak someone out show them how much a airplane wing or helicopter blade flexes when in flight. You need a slow motion camera to capture it but it freaks people out and has a tendency to make them not want to fly.

I was going to say the exact same thing! I love doing this to my wife every time we fly...her reaction is way too entertaining not to. She also makes it abundantly clear that she has no interest in hearing why it's a good thing.

Those in hurricane country know this flexing phenomena is the reason why the tall, skinny, twig-like pines are still standing tall after a storm yet the solid and fat 100 yr old oak is left blown over with its 20' root radius ripped out like a weed from a garden.

[ontherocks83]

Here is the tip of a Helicopter rotor flexing in normal flight. There is a better of video of this I am trying to find that shows what happens to the rotor when you put a load on it. Maybe A64 has some leads on that.

https://www.youtube.com/watch?v=Ug6W7_tafnc

[a64pilot]

I think that is a BO-105, a rigid rotor system, under a load the blade "cone" like the 787 does, blades also lead and lag and do what's called blade flapping to equalize lift, so they are moving forward and aft as well as up and down.
Helicopter aerodynamics are complicated, a Russian designer was quoted as saying you can take all the aerodynamic problems an airplane can have, and they still won't equal the problems of the tip on a rotor blade.
Look up the Brits BERP blade, it's been on the Lynx for years now

[crazyoldboatguy]

Skyscrapers also sway in the wind. The Willis Tower (Formerly Sears Tower) in Chicago, IL reportedly sways as much as 6" from center line in a high wind.

[hellosailor]

Some years ago a number of us rowdy passengers brow-beat an airline that no longer exists into using an unloved Electra during a near blizzard. As I was looking out the window and watching the wings FLAP that way, I decided that when a pilot says "I don't want to use that airplane" it was probably a better idea to agree with him.