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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

Something the article doesn’t mention is why this was phased out. Was it replaced with something similar?

> 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 Napier Deltic has a very distinctive sound. You can hear it in locomotive form on youtube. If you are into that sort of thing there are some really good videos on the Rolls Royce Crecy engine as well.

SysAdmin related: I was once talking to a fire chief and I asked about how much water the fire engines carried. He said that they carry about enough to put out the typical house fire. The first engine on scene immediately jumps to fighting the fire. The second engine on scene hooks the first engine up to the water supply before going on to fight the fire.

I've often thought about that when there's a work crisis: If I'm the second on the scene, what can I do to support those fighting the fire right now, before jumping in.

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

Anyone else struck by this bit?

Mack was awarded the contract to build the truck in 1964 and by the end of the year, the unit was nearly ready to hit the streets of NYC.

Seems amazingly fast by current standards. Those were the days!

And while we're talking about highly specialized firefighting apparatus... while I don't think Chicago FD ever ran anything quite like the FDNY Mack Super Pumper, they are well known for their use of a piece of apparatus known as a "turret wagon". Basically, it's a big-ass truck with a huge deluge gun (aka "monitor" or "turret") mounted on the back, and with a big intake manifold for receiving multiple supply lines. You could think of a "turret wagon" as being conceptually akin to the "Satellite" units that were part of the FDNY Super Pumper System.

Anyway, one of the best known Chicago Turret Wagons was "Big John" (aka 6-7-3).

https://chicagoareafire.com/blog/2013/04/chicago-fd-turret-w...

https://chicagoareafire.com/blog/2013/04/chicago-fd-turret-w...

Not sure if CFD still maintain any Turret Wagons in contemporary times or not, but variations on the concept are still found, particularly in industrial fire departments that protect high hazard sites like oil refineries, certain chemical plants, etc.

This thing feels like a mortal danger to the (up to 8x!) iron pipes / hydrants it's pulling from, that it'd want to just chew up the very pipes themselves! Or to the building it's hurling 37 tons of water a minute at! I don't understand how a connector hose wouldn't collapse, how it maintains any cross-section rather than being sucked into collapse.

Also wondering: what replaced this!

(Ed: great reply from Mindcrime. Also, the new Ferrara Super Pumper shows a very impressive ribbed(?) 8-inch "hard suction" hose! There's a whole wikipedia section for these drafting/vacuum hoses: https://en.wikipedia.org/wiki/Suction_hose)

Ah, the Mack Super pumper. Shame Mack started to struggle in the 60s until the 80s and got out of the fire truck business. They had some very interesting designs in terms of cab design and components. I always loved the F model cab-over which were produced until the early 80s which is what the CF fire truck was built on.

How do you extinguish an oil-well fire? Enter the "Big Wind" with two jet engines on a tank chassis. "The water is moving at a maximum rate of 220 gallons of water a second," https://www.caranddriver.com/features/a15138374/stilling-the...

There was a fire station we used to walk past when my little boy was about 2 years old. Often the fire trucks were out the front being cleaned. The fire fighters always let him sit in the cabin. Heaven for 2 year olds obsessed with trucks.

Indirectly related, for anyone interested in the topic, Pirault and Flint's Opposed Piston Engines[1] is a nice survey. Unfortunately it seems to be commanding a shocking price these days though.

[1] https://www.amazon.com/-/he/Martin-Flint/dp/0768018005

For the curious: most locomotive desiel engine designs have marine origins. That's because ships transitioned to desiel power (from steam) before trains did. At least in the UK. The general design constraints are similar and so when folks began looking into making diesel locomotives they generally selected existing marine designs and adapted them. Often de-rating the maximum power to improve reliability.

When the UK converted from steam to diesel it was easier to switch the locomotives while leaving the coach stock as-is. Modern trains aren't like this: they're "multiple units" with more than one drive car. Anyway, a steam engine can generate much more power than a 1950s diesel engine can, particularly factoring in the UK loading gauge which restricts engine height. So in order to make a diesel locomotive capable of taking over from A4 Pacific steam engines on the east coast main line, it was necessary to design a locomotive that had two desiel engines, with a high power to weight ratio. Hence the class 55 cited in the article. The deltic engines were very complex and costly to maintain but solved a problem arising from the transition away from steam. In the 1970s they were in turn replaced by trains with a DMU configuration (HST), featuring a permanently coupled power/van car at each end, removing the need for a single very high power locomotive.

That https://en.wikipedia.org/wiki/Napier_Deltic is pretty interesting.

You would initially think that the ignition events would be evenly spaced, but that's not the case. For every delta triplet, the ignitions come rapidly one after another, close together in the cycle.

In that second animation on the page, showing the firing order among 6 delta piston assemblies, if you keep your eyes fixated on any of the six columns, you can see the three firing events. Always C, B, A order.

I have a question for folks who handle pumps regularly. Almost all pumps are made for water, or sewage. How do you identify if a pump is rated to handle liquid metal or hot fluids (heated chemicals, or contents under extreme pressure)

I have never heard of a standard class of pumps for this....other than basically finding a manufacturer who specialized in these sort of pumps.

In case someone is interested in the engine powering this thing, a good writeup at https://oldmachinepress.com/2019/09/05/napier-deltic-opposed...

Simply posting here to introduce people to the Snozzle. https://youtu.be/_DNyAKcEe6A

Hello hath no fury like a lithium ion battery fire.

2400 hp sounds like a lot, but a Model X Plaid is 1020 hp. I assume it couldn't output 1020 hp for as long though.

The 'Curious Droid' video on this engine is fascinating. If I were more helpful, I'd leave a link to it

>and flow over 10,000 gallons per minute at low pressures if the situation called for it. When the pressure was ramped up to to 350psi, it could move 8,800 GPM.

That sounds counterintuitive . What about higher pressure will slow water down?

The price of the system was huge. It's a theme that as we move to better and more efficient systems they become more boring. Most of the magic of driving is lost in electric vehicles, biplanes, and the propellor planes of ww2 capture the imagination in a way jets don't. The monstrously complicated cabins of old 747s are fascinating in a way that modern far more capable planes are not. Back then you had 2 pilots and a guy whose main job was stopping the plane from falling out of the sky! Now it's a bunch of very clever computers under the cockpit that does all of that. It's worth noting that steam engine which was the driving element in the Industrial Revolution and maybe the most important invention in history was originally developed to pump water from mines. Some of these distant ancestors of modern engines are on display in London. James Watt might have predicted a pump like this, but he probably never guessed it would be pulled by anything but a team of horses!

Compare that to Sam Altmans wild prediction that agi will capture "the light cone of all future profits in the entire universe", maybe true, but it will never be as interesting as a steam engine, where the collective ingenuity of a century of engineers and metallugrists is on display in all it's glory.

the station: https://maps.app.goo.gl/Tc2Hs8kdwbFcbaxC6