View Full Version : Overseas (non US) tactics
FlyingKiwi
09-05-2002, 11:56 PM
I was asked recently for some info on tactics outside the US. This thread in the tactics forum just sort of happened. Give your perspective, especially non USA FF.
Maybe we can get some learning / teaching going.
http://www.firehouse.com/forums2/showthread.php?threadid=40849&goto=newpost
Kia Kaha Brothers and Sisters.
kiwi
BLACKSHEEP1
09-07-2002, 11:12 PM
Try www.firetactics.com they have some interesting thoughts on interior attack vs flashovers. I don't agree with all of what they have to say since I'm kind of a smooth bore guy and I would argue that much of what they do can be accomplished with that nozzle. But it is very well done and documented. They also get into flashover cause/effect and is very interesting reading.
FFMcDonald
09-08-2002, 04:19 AM
Here's something to think about....
Along with the fact that tactics are different - there is something underlying that is also different, and it dictates the tactics and strategy that is used -- Building Construction.
While in the military I was stationed overseas for 3.5 years - and was exposed to varied building construction the world over... from Africa to Europe and the Middle East.
There are also different trains of thought -- like higher pressures and smaller diameter handlines. Sexless couplings - on even the smallest diameter hoses...
I don't know that they are necessarily good ideas... nor are they bad- But rather just a different way of thinking...
FlyingKiwi
09-08-2002, 02:55 PM
in a single level dwelling. :p
CJMinick390
09-09-2002, 10:23 AM
Kiwi, I guess you're supposed to stage in the basement, if you have one.:rolleyes:
EastKyFF
09-09-2002, 11:30 AM
Note to fellow northern hemisphereans: Kiwi's people say they stage below the fire, but since everything in the southern hemisphere is upside down to us, they are actually above the fire. They don't get burned because fire burns down and out in NZ.
Other important Kiwi alterations:
1. Operation of aerials: Lower, rotate, and extend. Kiwi aerials actually drive to the scene with the ladder "up", according to American visitors, but Kiwis know the damn thing is "down".
2. Interior attack: Watch out for flashunder .
3. After the fire: They perform under haul.
4. PPE: They wear turnin gear.
5. Electrical safety: Watch out for underfoot power lines. Everyone's always afraid one of them will fall up.
6. Mistakes: "Don't screw down!" Kiwi commanders might say. And when it hits the fan, they say something is "SNAFD", not "SNAFU". And "it" hits the fan from the front.
7. Ventilation: Kiwi firefighters dig a hole, climb "up" into it, tunnel "under" the structure and cut a hole in the basement floor to let heat and gases sink down.
8. Vapor density: Oh, it's just too hard to explain.
9. Firehouse pranks: Darn tough to put a whoopie cushion on the chief's head, but that's what you have to do.
10. Arriving on the scene: Officer performs a size-down.
I know this is complicated, but in the interest of international understanding, you better try to get it. Otherwise you will get a major dressing up from your superiors. Or is it inferiors?
CJMinick390
09-09-2002, 11:59 AM
Thought that might be what happened, Kristen.:D
Temptaker
09-09-2002, 12:20 PM
Originally posted by FF McDonaldAlong with the fact that tactics are different - there is something underlying that is also different, and it dictates the tactics and strategy that is used -- Building Construction.
Great point. I was in Australia a few years ago, and noticed that A LOT of the houses have tile roofs, but are still wood frame construction. The majority also appeared to be above ground dwellings. Meaning that there is no basement. They are either single level, or ground floor entry with a secondary upper floor.
I was there during part of the wild fire season, and noticed a substantial difference in the smoke that was produced as well. I am assuming here, because of the nature and amount of the oils in the trees there that the wild fires burn hotter. Also the trees form a canopy, very often overlapping each other, making it easier for the fire to spread.
Oh Kiwi... lots of our Quints still carry booster lines ;)
FlyingKiwi
09-09-2002, 03:07 PM
EastKyFF
Thanks for giving every body the low up on the major challenges we face down to every day.
Don't get me started on the challenge of pumping air into the pond to get the water flowing down to the truck.
Oh my head hurts.
Cj, why stage in the basement, that is obviously above the fire anyway.
Kristen, you are supposed to apologise before making a mistake, it is the polite way here.
Tempie, you were probably looking at Eucalyptis trees, where the oil comes from. Nasty things that have a tendancy to explode when they get hit by lightning.
And Quince are a form of fruit to eat down here, we have Trucks. Our trucks are painted red, not yellow like a quince.
Fire304
09-09-2002, 03:43 PM
Kiwi, what do you wear for PPE? Besides the obvious vacuum bottle (sucks the smoke out of the air to make it clean ;) ) do you wear motorcycle brain buckets or FF'r helmets? Hoods? Long or short coats, leather or rubber boots? Etc.
FlyingKiwi
09-09-2002, 04:04 PM
Fire304.
Remember it is hot here in the summer.
PPE means Jandals(thongs) jeans, t-shirt, sunglasses (it is bright in there), a baseball cap. The worst part is having to feed the horses every day, we need them to pull the fire cart.
They make 'em tough down here pal.
Jokes aside.
We have two levels of fire fighting gear for PPE, strangely enough called Level 1 and Level 2, we don't get too complex down here.
Level 1
Used for Scrub / forest fires etc, as well as work around the station.
Leather calf lentgh boots, fire retardant overalls, leather work gloves, and a standard Pacfic helmets k4 battle bucket. (picture attached)
Level 2
We use Ballyclare Turnout gear, tan in colour with reflective striping. Knee length rubber boots with steel toe and heels as well as plates in the sole. Green structural gloves and the battle bucket.
SCBA is either Saber or Draeger, with the Draeger being more prevelant.
At an MVA we will use Level 2, with leather working gloves and rubber surgical gloves underneath. Goggles are also worn and the visor down to prevent blood splashes, and thats before any cutting out starts. A great soggy ball would be an accurate description on a hot day.
All of this gear is standard issue nationwide as we are a national Fire Service. Same with the trucks and equipment on them, it is pretty well standard from one end of the county to the other.
Training is done exactly the same way all around the country, boring eh. It also means when the next Brigade along shows up at your job, you can gaurantee they know exactly what they are doing and will do it the same way as you, handy eh.
Fire304
09-09-2002, 07:42 PM
Originally posted by Flying Kiwi
and a standard Pacfic helmets k4 battle bucket.
OMG! I've found it!!! Tactical Tupperware! :rolleyes: How do you keep it from chafing your chin, since you're always hanging upsides down the strap must bother you? Or is there velco inside the dome?
I figured you progressive guys must wear the european style.
As to the heat, even here, just south of the great white north, it gets warm. It's the second week of Sept and we just set a record of mid 90's today, and more of the same tomorrow. Its also very humid (of course). Last night I went to an MVA and was sweating before I even got my right boot on (left first), gear musta gained 15 pounds of weight in water before i took it off.
How do you do your dispatching is it regional or local? One thing I really hate up here is how hard and fast some of the political boundries are between different FD's. In a department I no longer work for I once sat on the appron with a full 2nd alarm response ready to roll as I watched the smoke from a structure in the next town over (about a 1 mile down the same road as the station was on). Since the chief in that town had not requested it, we were not to roll, period. They lost the building and never called us.
The town I now work in has a wide area of overlapping automatic mutual aid response. Any officer can call for mutual aid, and we do not hesitate if there is a delayed response.
FlyingKiwi
09-09-2002, 08:43 PM
304.
Despatch is carried out by Carrier Pidgeons, which seeing as how they fly upside down, end up pooping on themselves. :D
We runregional despatch centres using GIS mapping. The initial call is processed at one station, and once the address is given, it is pulled up onto the gis map and the incident logged. From this the system also recommends the nearest station/stations for attendance, as well as allocating a job number for the call.
This is passed to the dispatcher who handles the callout, and all incoming messaging. We have message units in the trucks that we can code directly to comms with info such as Arrival, type of incident etc. This is coded to the truck and logs in the system along with the time. Advisory messages over the RT are also logged.
After the incident is finished and we get back to the station we fill out the incident report on line (internet system) and the job is closed off.
One benefit to this system is that with building inspections, evactuation drilss etc being logged as well, we can start to get a pretty good look at a particular properties history.
It is also being used for finding developing trends within areas, regions etc.
We are also moving to having laptops installed in the trucks, giving all this info available to the OIC.
Not bad for a wee country that is the wrong way up eh.
:rolleyes:
FlyingKiwi
09-09-2002, 09:27 PM
Soooo many questions, such little time :rolleyes:
GPS = Global Positioning System.
Or "Where the heck am I"
GIS = Global Information System.
Or "Look at the map on the computer, thats where I am."
GIS can be combined with GPS coordinate systems, we use a private Garmin handheld if we need to give LZ info for rescue helicopters etc.
And as a point of interest, the computer has not got a clue what is happening at the scene Kristen. We get on the radio and give the code "Our pucker factor just hit 10, please send more trucks."
Which to your ear would translate as "Comms, 523. Make pumps X" where 523 is the truck number, and X is the number of appliances we need to lower that forementioned factor.
The laptop system is currently being trialled at a couple of stations.
There was some talk about GPS being incorporated into the trucks messaging units, which would report location every minute or so, I have no idea if or when this may be implemented.
do some searching on the internet, I heard a rumour you can find out about all sorts of things there.
CJMinick390
09-10-2002, 09:57 AM
Hi Kiwi,
Just have to pitch this into the non US tactics discussion. The really old crusties at our station remember a John Bean high pressure engine we had back in the 1960's. This unit produced high pressure fog streams from relatively small lines. I don't believe the stream was variable. At that time, the amount of BA was somewhat limited so the idea was you applied the fog through the door and or windows to smother the fire, much like the steam fire suppression systems ship board. I'm told it worked extremely well. The down side was that you could get really scalded if you were inside and the fog cloud rolled back on you. I think they ended up selling that rig to Saudi Arabia in the early 1970's. To some extent, it seems similar to what you all are doing now, without the option of pulsing a straight stream into the overhead, which I think is a great tactic that I myself use.
Some folks here seem to think that directing a stream into the overhead as you enter an area disturbs the "thermal balance" in the room and brings scalding stream down on the crews. I'm curious as to what your experience has been in this respect. With todays PPE, I'd rather get a little steam than get caught in a flashover.
FlyingKiwi
09-10-2002, 03:55 PM
CJ
The object is to put enough water in the smoke layer to lower the temperature, not turn yourself in a swedish sauna expert.
You pulse for a second or two at a time. Enough to suspend the fog in the smoke layer.
Go read Paul Grimwoods page on the subject at http://www.firetactics.com/GAS-COOLING.htm
Your method with a solid stream is the FIRST technique debunked by scientific studies.
All will be revealed grasshopper.
CJMinick390
09-10-2002, 05:18 PM
Kiwi,
Back in the murky days when I first got into this sort of thing, we were trained to get in close and use a wide pattern fog stream (60 degrees or so) to generate steam which in turn would cool the compartment and "smother" the fire. This seemed to work well, but you had to get in pretty close to the seat of the fire for this to really work well. There were also concerns about "pushing" the fire.
They're teaching the newbies here the "indirect" attack where you use a straight, not solid, stream from a combination nozzle. The idea is that it allows more penetration from the stream, does not push the fire as much, and doesn't bathe the crew in stream. Being a bit of a rebel, I'll set the nozzle so I get about a 30 degree pattern which seems to give a good balance of reach, cool air movement in behind the hose team, and will also generate a decent amount of fog to absorb heat. I'll check out Paul's site when I get a few free moments to digest it. This issue is an ongoing debate here in the states. A number of areas are moving to solid streams from their handlines to increase flow rates at lower pressures, which is a concern with long stretches in some of our larger exposures. This trend may also be partially driven by construction here in the states where buildings are not as well compartmented as they are in Europe and elsewhere. We have homes in our first due area where a single open space in the living area of the home may be in the neighborhood of 500 square feet or more and a wide pattern fog stream may be insufficient to penetrate to the seat of the fire.
From a thermodynamics standpoint, fog into the overhead would seem to be the most effective way of absorbing heat and lowering the flashover potential. I can see that short pulses would absorb the heat without generating inordinate amounts of steam.
CJMinick390
09-10-2002, 05:41 PM
A properly operating sprinkler system should pretty much take care of the fire on it's own or would at least dump enough water to lower a flashover or other explosive event. If the sprinkler system is not controlling the fire spread, I'm immediately thinking defensively since something unusual is happening and I'm going to be real cautious about operations.
FlyingKiwi
09-10-2002, 06:15 PM
CJ
Strangely enough 30 degrees is the recommended angle from the branch over here. moving to solid stream where necessary for penetration.
The scenario I presented in the Tactics forum was a "Pucker Factor 10" situation, where the room went into flashover just as we got to the doorway, my tactic at that point was not to make steam to cool a room, it was to stop from being fried myself.
You will always get steam when putting water on fire, you will not always get it when you are pulsing the thermal layer.
If you are getting it right, the pulses into the thermal layer will produce very litle to no steam.
Also what would you prefer, a bit of steam floating around, or the flashover igniting combustables behind you and your partner. I'll take the steam thanks.
While you are reading the firetactics site, have a browse at the Negative Ventilation situations Paul talks about.
Fire304
09-11-2002, 06:54 PM
Originally posted by Flying Kiwi There was some talk about GPS being incorporated into the trucks messaging units, which would report location every minute or so, I have no idea if or when this may be implemented.
Wow, GPS and horse drawn hand tubs, where do you get the electricity from? Steam dynamo?
FlyingKiwi
09-11-2002, 07:36 PM
Silly 304.
We have attached a wee generator to the crank handle for the siren.:rolleyes:
Tooanfrom
09-12-2002, 06:20 AM
Flying Kiwi--you have not put the order of firefighting as per our American brothers. #1 Person trained to drive truck(and only that)#2 Person trained to wear B.A(only that)#3Person to fight fire on inside/interior(only that)#4 Person to vent(only that)#5 Person to "break and enter"only that#6 Pump operater(only that) #7Ladder person(only that) #8 Hose person(only that) Any one of the 8 that forgets to turn up? Solution easy!! Just get a L.F.B trained guy in--and slot him in anywhere. This is tongue in cheek--so let me hear the howls!!
FlyingKiwi
09-12-2002, 07:31 AM
"Ell-Eff-Bee"
When I get up north next, the beers on me. :D
PS. Methinks the howls will be loud.
PSS. for those who really really like statistics. go to the following link and click on "Last Calls"
http://www.ufba.org.nz
You will notice that the last New Zealand Firefighter lost to fire in a building was in 1957.
FlyingKiwi
09-12-2002, 06:52 PM
Why is it that some days I just can't stop laughing.:rolleyes:
Rough Procedures
1. Pull up at fire.
2. OIC does survey, Driver gets pump running.
3. 3 and 4 get BA on and tags slotted into BA board. Tags have name, and Air Pressure recorded on them.
4. 3 and 4 advance line to structure. Leave a large bight of line outside to assist with movement inside.
5. Driver notes time of entry into structure for 3 and 4, and from the quick calculate list on the BA board, writes down the Time Due Out on the board, based on the lowest Air reading from 3 and 4. Time of entry is written on the tags. The board contains a built in watch.
6. After recieving instructions from OIC, 3 and 4 enter structure.
7. Driver makes a small note on BA board showing point of entry. Just in case you can not follow the line from the back of the truck and figure it out.
If there is no time, the tags may be hooked in a visible spot on the pump panel.
4 people, 5 minutes at the outside and the single level dwelling is searched and attack underway.
the latest gizmo is a small board with slots for the tags, as soon as they are inserted, a digital clock is started for each tag. This is then left at the pump so the driver knows exactly how long you have been wearing.
PS. Just for more fun, our large ladders (10.5 Metres or 34.5 feet) are made of wood.
FlyingKiwi
09-12-2002, 09:17 PM
Why is it that some days I just can't stop laughing.
Sir is the correct form of address for an Officer.
Me, I am one of the workers, call me "kiwi" or "hey you" and I will respond. Say "Sir" and I start looking around for the officer.
Or ducking for cover. :rolleyes:
stillPSFB
09-13-2002, 12:03 AM
Originally posted by Flying Kiwi
PS. Just for more fun, our large ladders (10.5 Metres or 34.5 feet) are made of wood.
Hey at least they don't conduct electricity like our monstrosities - instead of ladder companies, we simply carry a gigantic 3 fly aluminium extension ladder on top of the pumper. I can't remember the exact length but it is somewhere about 75 feet when fully extended. Takes six firefighters just to get it off the truck and deployed. They try to make us feel like a ladder company though by putting wind-down jacks on the bottom of the thing. :)
Great to see that the forums haven't lost their sense of humour in the last few months while I've been away from the computer.
FlyingKiwi
09-13-2002, 03:23 AM
Why is it that some days I just can't stop laughing.
5'3" would not reach the ladder on the back of the truck. :D
No hydraulic thingamy's down here.
Three people raise the ladder following a set evolution. My head hurts from laughing, so I will explain that evolution in a while.
psfb, I wonder why they are made of wood? could it be the electricity trick.
Kristen, it is nothing to do with theory, it is about tactics.
Theory.
When you have all the time in the world to decide what went wrong.
Tactics.
When you have one second to make your mind up, COMMIT and do it.
Fire304
09-13-2002, 01:45 PM
Originally posted by Flying Kiwi Theory.
When you have all the time in the world to decide what went wrong.
Tactics.
When you have one second to make your mind up, COMMIT and do it.
AMEN Brother
An early lesson in the USMC leadership training program is "A bad decision is better than no decision"
USMC = Uncle Sam's Misguided Children:D
Fire304
09-13-2002, 01:53 PM
Originally posted by Flying Kiwi
I wonder why they are made of wood? could it be the electricity trick.
You have electricity down there?
Whoa, that must really complicate things for you. How does electricty function upside down and backwards? :) :p :rolleyes:
Some departments up here use fiberglass ladders for protection from electrons, we use alum because its lighter and common sense to avoid wires and lightning (look up first).
Fire304
09-13-2002, 07:43 PM
Originally posted by stroutkristen
Could you have tactics without theories?
Sure,
Now here's a tactic that does not require much theory!
Run Like Hell
I suppose a little theory required for this one, but not much
When in doubt, punt.
Canadian tactics that require little thinking
I'll drink to that ;)
Or in the New Zeland version
that to drink I'll
While I suppose there is a theory behind it, you don't need to know it
Put the wet stuff on the red stuff
And the tactical golden rule
Play Safe
FlyingKiwi
09-13-2002, 07:59 PM
Brainless tactics.
Uh we need a line here.
Duh put BA on before entering smoke.
Umm need ladder to get to second floor window.
And it is CORPS. announced Core.
A CORP is halfway between a Cough and a Burp.
FlyingKiwi
09-16-2002, 06:20 AM
Just bumping this back up with a partial quote from jimthefireman, from the tactics thread.
Any comments.
A couple of things that we do differntly here in NZ is to connect the booster pump in series with the main pump manifold giving us a working pressure of 500 to 600psi on a flow of 45 US gallons per minute at the (elkhart) nozzle. The higher pressure reduces the droplet size and so increases the heat absorbtion capacity enormously compared to other lines.
When we stretch layflat hose we use 75 foot lengths of two and three quarter inch hose to get the water to the area of the fire with a single 75 foot length of one and three quarter inch hose off the end for its manoeuverability. It gives you the benefit of the 1 3/4" at the sharp end without losing pressure most of the way there from the pump.
Fire304
09-16-2002, 04:50 PM
Most of our hose up here would fly into itty-bitty pieces-parts if you ran more than 400psi into it, some is only rated 200psi. Although I like the idea of small water dropplet.
Your trucks have two pumps on them? Some of our older engines have "dual stage" pumps, but most newer apparatus use a single high volume pump.
We've been known to streach out a 1 3/4 preconect with 2 1/2 for long lays into a building. Sometimes we'll put a wye at the end of the 2 1/2 and feed two hand lines, but at least in my district there is rarely a need to pull that far.
Do you use Class A foam or CAFS at all?
FlyingKiwi
09-16-2002, 05:56 PM
The High Pressure line is a solid reinforced hose, not layflat hose.
The HP line is carried on one or two booster reels, depending on the truck model.
The object of the dual stage pump is the HP line can be operated at the same time you are running the 2 3/4 (70mm) lines at their lower pressure, higher volume.
What you call a wye, we call a Breach. Two types, Collecting Breach, and Controlled Dividing Breach, with the CDB you can get one line working while the other is setting up, then flow the water when required.
yes we use CAFS and Class A. CAFS is not all that common.
Fire304
09-16-2002, 07:26 PM
Originally posted by Flying Kiwi
What you call a wye, we call a Breach. Two types, Collecting Breach, and Controlled Dividing Breach,
Interesting that you use a different name. Your CDB is our gated wye. A collecting breach I'm gonna guess is our clappered siamese.
That's nice that you have the ability to run two pumps that way. One of the reasons I believe we "need" engineers is that trying to pump multiple pressures into different lines without given the boys on the knob a thrill ride requires experiance.
FlyingKiwi
09-16-2002, 07:48 PM
On the prssure gauge for the HP line is a big red stripe, that is the "Do not go Past" setting, go past it and the pump dumps out on the road. Same on the LP lines.
It does not need an Engineer to run it. If you have two LP lines running together it is just a case of balancing the pump output to what the gauges are showing. If one line closes off, then you back off the pressure for the other line.
Simple really.
PS, if you see two sad faced Firefighters pass over the top of the truck hanging on a line, back the pressure off.... FAST.
FlyingKiwi
09-16-2002, 08:27 PM
Forestry Hose.
41mm, 1 1/2" Canvas percolating hose. Has a threaded male / female connector.
45mm, 70mm, 90mm
1 3/4", 2 3/4", 3 1/2"
Layflat hose, non-percolating.
These use the British Instananeous Coupler. Click one into the other and thats it, sealed by the water pressure.
It really is very simple.
Collecting Breach.
COLLECTS water from two lines and puts it into one, straight through no control over flow.
Controlled Dividng Breach.
DIVIDES into two lines, each with its own screw valve to control output.
Adapters.
4" to Instantaneous adapter.
Instantaneous to Forestry Adapter.
Male-Male, Female-Female Instantaneous Adapters, commonly called "Stuff Up" adapters, because you have run a length of line the wrong way you plonker.
So a typical scenario in a rural setting might involve.
Portable pump at water source with a Dividng Breach. Running 2 lines of 3 1/2" to the truck. Two High Pressure Lines being used from the booster reel for the Search/Interior teams. 2 Low pressure 2 3/4" inch lines being used for external work, one of which has a length of 1 3/4" off the end for mobility.
2 x 3 1/2" lines feeding off the first truck to supply a second truck when it arrives on scene. This truck can now run 2 x High Pressure, and 4 x low pressure lines.
10 lines working from two trucks.
Branches are the bits on the end of the fire hose that spray water. Nozzles are personal.
Our main Branches are Elkhart models, variable from jet to fog, and variable output settings.
We pretty much only use solid Branches for Forestry or setting up monitors.
For a temporary monitor we will stuff a length of 2 3/4" line through a length of suction hose, put a solid tip on the end, pack it to the angle we want using coiled hose underneath, and then clear off.
PS. If I started shouting for a "Clappered" anything on the fireground,it would mean I needed something that was already broken.
:rolleyes:
FlyingKiwi
09-16-2002, 10:39 PM
You guys are weird...2 3/4"?
11,000 Firefighters (Kiwi's that actually fight fires) would give you a slap up the side of the head for that one Kristen.
I have been nice and converted the Metric to Imperial measurements for everybody. I am old enough to well remember when we as a country changed to metric, and can change between them easily enough.
So what if we use 70 mm line for our Low Pressure attack line.
Can you PLEASE explain how that makes us weird.
And thanks for explaining how Branches work, I would never have guessed.
When you say 1 1/2"= 125 GPM, is that the maximum pressure for the line, or is it at a set PSI rating, how much water do you get for lower or higher PSI ratings.
How many lengths are involved, what is the vertical rise of the lengths. Ain't friction loss a mongrel.
At the end of the day, when someone over here shouts "More water." they get... More Water.
All of this information comes from me.
FlyingKiwi
09-17-2002, 01:23 AM
And how is sarcasm not offensive?
DON'T BOTHER ANSWERING THAT QUESTION.
FlyingKiwi
09-17-2002, 01:34 AM
.
FlyingKiwi
09-17-2002, 04:46 PM
And thus endeth a simple lesson in tactics.
CJMinick390
09-17-2002, 05:06 PM
Does this mean she is gone again?
NightShade
09-17-2002, 05:06 PM
I do believe if some should stop taking their brain out and playing with it and then not replacing all the parts...................
Fire304
09-17-2002, 11:29 PM
Originally posted by Flying Kiwi
When you say 1 1/2"= 125 GPM, is that the maximum pressure for the line, or is it at a set PSI rating, how much water do you get for lower or higher PSI ratings.
Not sure where she got her numbers from, but "we" (being my group of FF's) tend to plan our flows based on line size. Older 1 1/2" stuff is generally considered good for 100gpm, that's based on the max you can push through the hose before you start to cavitate the hose itself. Any more pressure = no more water and a shorter reach from the "branch". In "normal" situations you can get this flow from the hose regardless of friction loss or elevation up to the point where the hose is so long you have to over pressure it to keep 100psi at the knob. Bear in mind I say "regardless" I mean the engineer is working his ass of to calculate friction loss and such.
Now friction loss is where pumping up here gets "fun". Since we run several different sized hoses, and some companies pull different leangths of preconnect with different nozzles, if you're working 4 lines, each has a different pump pressure to play with to keep the nozzle pressure at 100psi for fog, and 50psi for smooth bores. If one line shuts down you have to adjust all the others to keep from seeing the firemen flying over the truck.
Which reminds me a of a brush fire I went too one. We do have some highpressure trucks up here! Most of our dedicated foresty trucks are designed to run at 400psi (vs. 200 on structural). Actually, they look a lot like your trucks, booser reels, some flat lay, 4wd short chassies. One firefighter was filling indian tanks (portable backpack style personal pump extinguishers used for brush fires) with a HP line when another hand line was shut down. This FF'r was standing in the bed of a pickip truck and not paying as much attention to what was going on as he should have been, nor was the pump operator who did not notice the rapidly increasing pressure. In the end two guys with indian tanks on were face down in the mud, the guy in the pickup few about 20' before he thought of shutting the hose down, and we all got one hell of a laugh seeing this very monety-pythonish attempt at firefighting.:D As luck had it, nobody was hurt.
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