Titanic tourist sub goes missing sparking search

[berndo]

Not exactly. DIN thread is 5/8 - 14 BSP (British Standard Pipe). That is different from imperial threads used in US.
It is a relic of the past, but DIN standardised it because that thread was common here in Europe.

If the British 5/8 and the other old British units are not imperial what are they?

 

[BackAfter30]

As said, the only physical quantity relevant for evaluating an explosion/implosion is the energy released, which I estimated at the best of my (limited) knowledge.
If you can provide a better estimate of this quantity, please post your data.
Computing the total force on the vessel is meaningless, as the force is distributed on a convex shape, hence its resultant is null.

If you go back and look at my post, you'll see that it was simply subjectively relating the forces involved to a (for some folks) more understandable expression of those forces. I didn't say your calcs were wrong, simply that they were off point related to my post.

 

[Angelo Farina]

If the British 5/8 and the other old British units are not imperial what are they?

The difference is in the thread angle.
The BSP standard uses a thread angle of 55°.
In US the threads have a 60° angle...

Thread angle - Wikipedia

en.wikipedia.org

 

[BackAfter30]

The Apollo program was entirely done using SI units.
The usage of imperial units in space programs caused some big errors, the most famous one was the crash-landing of the Mars Climate Orbiter: How NASA Lost a Spacecraft From a Metric Math Mistake | SimScale

The fact that imperial units were used at all was the trigger; they probably had no business being in the project at all. It was a project management/system engineering failure that allowed that trigger to result in the loss of the vehicle.

 

[Wookie]

I don't think engineers in the US use inches and feet.

Interestingly, I work in ship design and repair.

Yes, we still use inches and feet, and have imperial wrenches, as well as adjustable wrenches for the crap that slipped by the Buy American program.

The LCS ships are designed in imperial, built in imperial, using commercial off the shelf products that are not subject to Buy American. The German Renk Reduction gears are junk, causing the US Navy to scrap 9 ships less than 10 years old. The diesels are Colt-Pielstick, and we have to bring in tech reps from France, because they just aren't rigorous enough for the job. The Chinese wiring supplied doesn't meet Mil-Spec. So it isn't tinned marine copper, its household copper crap, stranded, but not tinned, resulting in miles of replacement cabling.

Meanwhile Bath and Ingalls built destroyers and carriers are designed and built to last 50 years. They ain't cheap, but they are cheaper than scrapping them every 10 years because the foreign built crap isn't strong enough. Even after they are bombed (Cole), torn up in a collision (Fitzgerald, McCain), or burned in an industrial fire (Oscar Austin) they are worth repairing instead of scrapping.

 

[Angelo Farina]

If you go back and look at my post, you'll see that it was simply subjectively relating the forces involved to a (for some folks) more understandable expression of those forces. I didn't say your calcs were wrong, simply that they were off point related to my post.

And here is the point!
You continue to talk about "force".
Force is not relevant for explaining what happened or for assessing the amplitude of the sound pressure pulse generated by the implosion.
The relevant physical quantity is energy, which can be expressed in many different units.
If you do not like Joules or kg of TNT, we can express this quantity in other units.
For example, 95 kg of TNT are equivalent to 1100 kWh.
Or, if you prefer to use British Thermal Units (BTU), it is equivalent to 3700000 BTU.
Problem is not units, it is using force instead of energy.

 

[berndo]

Yes, we still use inches and feet, and have imperial wrenches, as well as adjustable wrenches for the crap that slipped by the Buy American program.

The nuts and bolts and wrenches but the combustion chambers volumes and the stuff that on the design side in metric, right?
Even the US made cars don't give the engine size in gallons or ounces but in liters or cc, no?
AFAIK, companies like Tesla buy lots of components from Europe and Asia. If all your development is in imperial, it would be a major PITA to use a different system than all your suppliers.
I don't know anything about ship building though.

 

[Manatee Diver]

As stated, Germans invented rockets.

The modern liquid fuel rocket was invented by Goddard in 1926. His was an American from Massachusetts. Van Braun was still a young teenager.

 

[broncobowsher]

It's also interesting to see the number of things designed from scratch in metric units that have a dimension of, say for instance, 25.4mm, or something similarly related to base imperial units.

Like all the electronics stuff. Odd metric spacing is standard, which if converted to 'Merica standards comes out as nice inch spacing.

And lets not forget the Whitworth thread. You probably have some and don't even know it. Camera mounts are Whitworth threads. But the threads cross over to standard American sizes that it doesn't matter and nobody really cares. Even with mis-matched thread pitch the fastening is way stronger than a camera can ever use.

 

[berndo]

Like all the electronics stuff. Odd metric spacing is standard, which if converted to 'Merica standards comes out as nice inch spacing.

What spacing is that?