61–70 of 127 posts
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Tangentially related and recommended. Werner Herzog's film that also features longer sections on the fire fighting efforts on the oil fields. https://en.wikipedia.org/wiki/Lessons_of_Darkness
For lighter viewing there is Sorcerer (1977) [0] with Roy Scheider. [0] https://en.wikipedia.org/wiki/Sorcerer_(film)
That "deltic" engine just for the water pumping is incredible, I'd never seen that cylinder layout before. > https://en.wikipedia.org/wiki/Napier_Deltic
> The Napier Deltic engine is a British opposed-piston valveless, supercharged uniflow scavenged, two-stroke diesel engine Any tech that includes the word “scavenged” must be cool and efficient
Generally speaking at least, two stroke diesel engines weren't super efficient, but did offer great power output relative to their size.
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Our engine holds 1200 gallons. It goes in first* and starts putting the wet stuff on the red stuff. As the engine drives in it drops a 3" hose along its path. Next is our big tender with 3000 gallons. It stops at the street and connects to the dropped hose to pump more water up to the engine. The tender also has a drop tank -- think about a portable kids' wading pool but much larger and deeper. Shuttle tenders refill…
H-h-how did you learn this?
Earlier quoted context omitted.
Tangentially related and recommended. Werner Herzog's film that also features longer sections on the fire fighting efforts on the oil fields. https://en.wikipedia.org/wiki/Lessons_of_Darkness
For lighter viewing there is Sorcerer (1977) [0] with Roy Scheider. [0] https://en.wikipedia.org/wiki/Sorcerer_(film)
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The article says the "super pumper" could supply 8,800 gallons per minute, and it came with three "satellite trucks [...] not burdened with a pump of their own" Your basic modern fire pump unit can pump 2,200 gallons per minute (if you can find a water source that'll give you that much) and it'd typically have a crew of 4-5 firefighters on board. So you'd probably replace it with 4 regular fire trucks? Then you've go…
(if you can find a water source that'll give you that much) Note that, for what it's worth, fire pumps are generally rated for their capacity when drafting from a static water supply (think, pond, lake, river, etc). Basically all modern fire pumps can easily exceed their rated capacity by a pretty good margin when pumping from a pressurized source, but then you're back to your point of "do you have a source that can…
At the major Grenfell Tower fire, the water network could only supply ~4,320 litres per minute (1141 us gallons per minute) [1] despite firefighters asking the water suppliers to maximise the water supply.
And that fire was attended by seventy fire engines and two hundred and fifty firefighters, as they needed pretty much all the breathing apparatus in the city. So they had substantially more pump capacity than they had water available.
[1] https://www.insidehousing.co.uk/news/lfb-did-not-follow-even...
My dad worked on the Space Shuttle main engine program in the 80s. One of the things they built was the turbopump [0], which generated 23,000HP (and could drain your average home swimming pool in one minute). Seeing the test firings of the pump was pretty amazing, draining one "swimming pool" and filling another in a minute. [0] https://en.wikipedia.org/wiki/RS-25#Turbopumps
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(if you can find a water source that'll give you that much) Note that, for what it's worth, fire pumps are generally rated for their capacity when drafting from a static water supply (think, pond, lake, river, etc). Basically all modern fire pumps can easily exceed their rated capacity by a pretty good margin when pumping from a pressurized source, but then you're back to your point of "do you have a source that can…
In the UK a large-scale fire will often be attended by far more fire engines than the local water network can supply. At the major Grenfell Tower fire, the water network could only supply ~4,320 litres per minute (1141 us gallons per minute) [1] despite firefighters asking the water suppliers to maximise the water supply. And that fire was attended by seventy fire engines and two hundred and fifty firefighters, as th…
> During a fire in the Bronx, firemen laid 7,000ft of hose to get to a suitable water supply and the truck pumped as though it was dipping its feet into the ocean. "7000 ft" sounds wrong to me. That's over a mile of hose. Feels like that's unnecessarily long. I'd love to learn more about this. Anyone know when or what fire this was?
The article mentions that the main pumping unit could draw water from 8 hydrants at once. So 7000 ft of total hose to get to 8 hydrants sounds like it makes sense. I wonder if maybe it can't even use hydrants that are too near each other in the plumbing graph.
There's a lot of variables in that equation. For example, say you have a "dead end" main that ends somewhere near the fire. If you connect to the last hydrant on the main and start flowing water, there's a good chance you won't get a lot of additional water by connecting to the next hydrant up the street. But if you connect to a hydrant that's on a main that is part of a loop, there's a better chance you'll be able to get more water by doing that.
And without getting into too much detail that would be boring to non-firefighters (probably)... there's actually two big variables for a given hydrant: the maximum volume of water it can supply (in GPM) and the pressure available at the hydrant. And those two things are related. Anyway, net-net, you can have a hydrant that is capable of - in principle - flowing, let's say 2000 GPM. But the pressure at the hydrant is only, say, 40 psi. That means you only have 20 psi (approximately) available[1] to overcome the friction loss in the supply hose between the hydrant and the engine. And that friction loss in turn is a function of the hose size and the flow rate.
Anyway, that results in a situation where you might have a hydrant that could supply you 2000GPM, but if your fire is, say, 1500 feet away, you might effectively only be able to take advantage of maybe 500GPM of that.
And that in turn leads into stuff like using a "four way" or "hydrant assist" valve, or having a relay engine sitting right on the hydrant (to minimize friction loss between the hydrant and the engine) and then using its pump to boost the pressure going to the attack engine. By using multiple engines like that, you can get closer to achieving that hypothetical 2000GPM (or whatever) flow.
It gets pretty complicated, but fortunately fires in urban areas where the municipal water system is the limiting factor seem to be relatively uncommon (but not unheard of!) in this day and age.
[1]: because you don't want to pull the residual pressure down too low or it can damage the water system, supply hose or your pump.