Hull Integrity down to such and such percent!!!

I've always wondered (voyager and DS9 are both notorius for this....) During battle, as the ship takes damage and sparks are flying all over, you hear Tuvok, Nog or Reed yell out: "Hull integrity down to __ %!!" What does this mean exactly? If my hull intergrity drops to say 40%, does that mean my ship is physically full of holes? or is it something to do with the molecular structure of my hull being only 40% of what it was before whatever damged me? How would you gauge Hull Integrity in real-time besides basically knowing my hull is damaged and where the damage is? how does that translate to a percentage in real time?

 

It means the ship is about to fall apart and everyone aboard is going to die.

 

Here are actual possibilities as opposed to being full of holes. Either the sensors measure the strength of the hull and hull integrity is the percentage of that hull strength, or it is related to the structural integrity field strength, or perhaps both somehow.

 

I take it as a shorthand for saying that, in its current state, the ship is estimated (by computer simulations) to be able to take about, say, 40% of the beatings it was able to withstand before the start of the battle (be it for weakened structures, actual holes in the ship, or a damaged integrity field).

 

It can also mean that it is under some sort of transient stress. The hull is likely made of material (like steel) that can rebound easily and will NOT fatigue. Unlike aluminum that will eventually break from on and off force being applied to it.

 

Unfortunately I'm not sure of the names of the instruments, but aren't there instruments in the 21st century that can be used to determine if there is abnormal stress on any part of a structure such as a building or bridge? Could that--combined with a measure of the structural integrity field--be in use?

 

It's a plot device used to 'raise the stakes' in an already tense situation

Why didnt they take the Wing Commander 3 road. Give your ships some armour and when torpedoes blow it all away you start taking some critical damage

 

They did that with the Defiant with her ablative armor.

 

It means it's time to send Crewman Deadmeat outside with a roll of duct tape.

 

Since sometimes they indicate hull breaches, even though structural integrity still might be in the 60's, I bet that once it reaches 0 you have total space-frame/SIF failure.

But basically it's just somewhere to go once you say 'shields have failed'.
I prefer "SHIELDS COLLAPSING!" ala Scotty, but that's just not how the 24th Century shows did it.

Bonus: Take a shot every time the word "signature" is used on ENT.

 

It could well be that "hull integrity" actually refers solely to the strength of the structural integrity fields, with 100% indicating full fields and 0% merely the physical strength of the hull itself, which as such may be negligible.

That way, integrity can go down to 40% under heavy fire yet quickly be restored to 85% when the enemy veers off and be back to 100% without the repair efforts of hundreds of welders - and without the need to show any of this in the form of visible external damage to the ship.

Timo Saloniemi

 

Heck, they're actually 20th century technology. Strain gauges.

 

The hull is only able to withstand 40% of the stress it was able to in peak condition. Problem is, such a hull would collapse long before reaching 0%...

 

...Which is why the idea that all these percentage points are "extra", afforded by the structural integrity fields, and that zero percent corresponds to the passive integrity of the hull rather than to total disintegration, is rather helpful.

Timo Saloniemi

 

Yeah, but I never understodd what the "structural integrity field" actually is.

Is it so some sort of energy field that reinforces the Hull? That's quite similar to shields, isn't it?

Hence why I chose to interpret it as a measure of the Hull's resistance itself in that post.

 

Or the scale is calibrated that 0% is 5% above the theoretical collapse point.

 

I;ve always liked the idea of a structural integrity field finding a way to share the strength of something.

Imagine if you will, a heavy steel combat tank with sensitive antenna on top. These would get easily ripped off the tank that would remain. Even before TNG, I had this idea of a way to share strength--to where every bolt had the strength of the total construct--meaning that the force needed to destroy the whole tank was needed just to rip off the antenna--and that was only if you got past the force field.

 

I like this explanation and it's what I would've gone for. As regards the SIF it's a (kind of) forcefield that indeed helps to hold the ship together against, amongst other things, shearing stresses caused across the spaceframe by warp flight

 

They are talking about SIF. They actually call out hull breaches when they happen.

 

One could argue, though, that there are structural failures other than hull breaches, and that the ship could well have structural integrity drop down to 47% before she starts venting gases to space. It's not as if our heroes ever call out things like "upper keel bending!" or "lateral spars five through eight just snapped!".

Timo Saloniemi