Just a little survey to see what people think about hitting a fire with big water in an initial attack from tank water. Let's use a 500 gallon tank for the example.
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Thread: Blitz attack from tank water
02-23-2000, 01:39 PM #1BIG PAULIEFirehouse.com Guest
Blitz attack from tank water
02-23-2000, 02:24 PM #2e33Firehouse.com Guest
We are lucky (if u can call it that) to have 1000 gallon booster tanks. Our 1st due has 4" tank to pump piping with full flow valves. Our water supply can be questionable at times once tankwater is used, but thats for a different day.
Had some fires in the last few months that both seemed like classic tankwater blitz senarios. Both were shortstaffed crews with heavy fire showing. With the prepiped deck gun from the street I still feel alot of fire would have been snuffed. As the MPO runs the gun the other one or 2 guys could have been stretching the handlines to put them in service once the main fire was blasted. Instead the 125GPM handlines came off first and water was wasted..both places were a loss. I cant say for sure, but I have to believe a 500-1000GPM stream would have mad life easier and saved property. Try to convince the old schoolers that you arent wasting water though and maybe we will move into the future. Ill likely get a bad rap for this if anyone reads it, but its true. I wish there was a way to show them how well it works in real life. I really want to get some blitz handlines on the engines too. Our current 3" line has a nozzle only capable of 250GPm on it. If I could get a higher flow nozzle or a tailboard deck gun on each engine I'd be happy.
The opinions and views expressed herin are solely mine and not on the behalf of any department or organization I belong to.
02-23-2000, 02:56 PM #3DaronFirehouse.com Guest
I am a firm beleiver in big water for big fires. In most situations you are better off hitting the fire fast and hard to at least slow down its growth if not knock it down. In most, but not all, fires that I have encountered this holds even more true for limited water supply problems where you have to wait for additional equipment to establish a steady flow of good water. One of the engines I run on has a 1000 gal booster tank as well which makes this a whole lot easier but I do run on a engine that has a 500 gal booster tank too and the same applies to it. You can knock most fires with this and wait for additional water if that is what it takes. Most of our water is being used for overhaul anyway. When you consider that the average fire doubles in size every minute you have to at least slow it down as soon as you can to prevent a fully involved fire. I do have to agree with e33 that this is almost impossible to tell this to the old timers. Most that I have talked with also say you must conserve your water in these situations. This only insures you will need lots more water as the fire is going to keep growing. I have the same problems talking about LDH, they say there is not enough water there to used this size hose but in reality the less water supply you have and the further you have to carry it the better off you are with LDH but that is again another story.
02-23-2000, 07:01 PM #4Capt. ZadaFirehouse.com Guest
Our blitz line is either a 2-1/" or 3" hose with an 1-1/4" solid bore tip at 50 NP. This gives us around 325 g.p.m. At least we hope that it is at least 50 NP. Without a Pitot or flow meter, it is just a calculated guess. I would like to push it to 400 g.p.m. at 80 NP, but our tank to pump piping is only 2-1/2" and might cause pump cavitation.
The next truck will have extra large tank to pump and discharge plumbing to enable us to give it a squirt with a "Big Paulie" & or "Blitz Attack Vindicator". Oops, I mentioned them again.
Edit: I forgot to answer the question. Yes, yes, & yes use your water and hit it as hard and as soon as possible.
[This message has been edited by Capt. Zada (edited February 23, 2000).]
02-23-2000, 07:26 PM #5Dalmation90Firehouse.com Guest
Excellent tactic, used with caution and understanding a little math.
Sorry Paulie, but it's tough for me to think in terms of "500 gallons"...our two Engine-Tanks are 1200 gallons; our Engine is a 750 gallon (unfortunately, no 2.5" preconnect and no room to fit one, but it's primarily an LDH water supply truck); and we have low-water tactics used with our Ladder and Service (both 200 gallon tanks)
I will say usually we will use 1.5" and 1.75" lines to cut off fire spread first if there are interior partitions to work with. 95gpm+135gpm=230gpm...1200 gallon tank will last just a hair over 5 minutes.
Which works out real well because we can figure on the 2nd in ET arriving about 5 minutes after the 1st.
But then we have a real fast ramp up -- figure on water arriving at the following intervals, since all are dispatched simultaneously:
1st due........1200 gallons......0 minute
2nd due........1200 gallons......5 minute
3rd due........1000 gallons......6 minute
4th due........1000 gallons......7 minute
So we can pretty much figure at 6 minutes in, we've exhausted the first 1200 gallons and have 3200 gallons still to work with.
So we have two choices in blitzin...
One) Blitz off the first ET -- 350gpm = 3.5 minutes of water. As a former Chief told me, great if it works, but make damn sure you get it on the first shot 'cause if the 2nd due ET is slow getting there you look really incompetent to the property owners with fire burning and no more water.
Two) Confine the fire with small lines. Meanwhile get the 2.5" in position, and as the ETs start pulling in at the 5 minute mark begin a Blitz -- 350gpm will last 9 minutes (your now 5min + 9min in...14 minutes so you have time that either a laid line is in place or the next round of mutual aid tankers are arriving) Alternately, you could stretch 2 -- 2.5" blitz lines or a 3" to master stream and use 700gpm x 4.5 minutes. You're now talking some serious knock down; you're only 10 minutes in when the tankers give out so it might be tight to have established a long laid line or for the next round of tankers to arrive.
Two variations I've seen -- 1, using the blitz attack to cut off extension since there was no interior partition to work the small lines against and only a short lay to a pond was needed for big water to be flowing to take over from the Blitz, and 2, a good sized (3500 sq ft?) building fully involved. It was on the district line so two ETs arrived simultaneously from opposite directions. Hydrant was 300' away, so both pulled up and whopped the snot out of the fire with a two deck guns and dumped 2200 gallons on the fire in 1 minute, while handjacking a 5" line to the hydrant for mop up afterwards.
Blitzing has been a popular tactic that most of the trucks in our area have been setup for since the sixties/seventies; partly an outgrowth of pump-to-tank plumbing tests done in the 60s in our area that got trucks that could pull 500, 750, 1000+ gpm out of their tanks and made the blitz possible. I've got a picture somewhere of Muddy Brook using a 4 man, 4' long piece of iron pipe with handles welded on and a fog nozzle on the end back in the sixties! Actually, if you work the math back in one of the scenarios above, I am counting on tank to pump flows of at least 700gpm to support them.
Anyway, the math above is pretty simple for anyone to figure out. Probably not at 3 in the morning, but you do it one slow afternoon. You know what you carry; you know what you have coming in and how long you usually take to get water supply established. It's from knowing that math and how long our mutual aid usually takes to arrive we can figure 5 minutes with small lines & always water vs. 3.5 minute blitz to knockdown and a 1.5 minutes before next water. Again, that means if we're confident of the fire size & that the m/a tankers are responding, we'll blitz. If we're not confident the blitz will knock it down enough or especially if the m/a tankers are delayed, we'll position small lines to cut off extension and conserve water until the tankers arrive.
Hopefully if you have only 500gallons to work with, you have a hydrant nearby to hookup to after the blitz
One last thing, fully agree with not using small lines on the big fire -- but we're not using them to hit the main body, there being played against interior walls, etc to keep/slow the fire from extending into new areas of the building. Walls are your friends -- they can make the water/class A/cafs go a lot farther in confining a big fire than putting a little water directly on it would.
02-23-2000, 07:36 PM #6StaticPressureFirehouse.com Guest
I am not going into Calculus on this issue, but it is safe to say that a fast hard hit will help you out. As for pre-planning a specific trucks arrival time and basing your attack on that you are getting into troubled waters. In an urban area, where I am we often have stations a mere 1/4 mile apart and you can sit around and say the second due will be here in 2 minutes. But Mr. Murphy raises his head and the second due won't crank. Anyway, hit it hard but remember that the tactics you play with you have to live with. Stay Safe!
Disclaimer: The views expressed in this post are purely mine and not that of the department or any associations of which I am a member. They have their own ridiculous views.
Stay Safe and Stay In the House!
02-23-2000, 08:02 PM #7SOMLFirehouse.com Guest
Heavy fire on arrival...blitz it.
even though we run 1000 gal engines my answer would not change with 500 on board. Hit it hard and knock it down quick. we use the prepiped deck gun and a 2 1/2" preconnect on a regular basis.
works great on attached garage fires.-
02-23-2000, 08:38 PM #8Dalmation90Firehouse.com Guest
It's not entirely pre-planning specific trucks...we know how much time it usually takes. Then the Officer-in-Charge needs to make sure they actually got on the road in the expected time frame, and factor in things like snow storms, etc! A blitz in a blizzard takes more thought since if you don't get it, your next water maybe another 15 minutes away. Maybe plan 350gpm for 2 minutes, then use the remaining 500gallons sparingly until more water gets there. You're in the same situation if you already have one working fire and nearby companies are tied up there -- long delay to resupply.
At least with three more ETs coming, hopefully at most two will hit each other on the way and third will still arrive!
02-23-2000, 09:29 PM #9benson911Firehouse.com Guest
A question to those who advocate the "Blitz attack" from a pre-piped deck gun...Noone's home right? How do we know this? In the time it takes to make sure everyone's out, you can position your 2.5" and apply the water to the seat of the fire not just flowing at the fire showing from the street.
I guess I just don't understand the need for the blitz attack unless you're protecting an exposure by knocking down the venting fire.
I'm not trying to be mean or facetious...just explain to me the advantage to hand lines, other than keeping FF away from fire (safety.)
02-24-2000, 09:01 AM #10Bob SnyderFirehouse.com Guest
I've seen companies do this over and over again, and it has rarely produced good results...the typical scenario goes like this:
Engine pulls on the scene and sees fire through the roof and out 1/2 of the windows and immediately wagon-pipes it. 30 seconds later (500 gals through a 1000 gpm gun), the fire is still blowing out all over the place, the surrounding trees and brush are catching, and the engine sits there empty, waiting for supply to be established, unable to support the already slim chances of search and rescue, unable to cover exposures, unable to protect itself from the ensuing brush fire, etc.
Before you open that gun (or that high-volume line), you've got to consider whether the water you have on board will get the job done in a blitz situation, when you can expect a water supply to be established, whether the water you have would be more effective if strategically deployed through a few hand lines, whether you have more useful and important things you could do with that water, like cover a search or protect uninvolved exposures, or whether blowing the tank will leave your rig (and you) in danger.
Just putting the wet stuff on the red stuff fast isn't always your best option. In fact, there are occasions when attacking the original fire is one of the lowest priorities.
02-24-2000, 09:48 PM #11LT trk106Firehouse.com Guest
WHAT ABOUT THE PRECONECT PORTABLE MONITER? WE CARRY OURS WITH 100FT OF 2 1/2" AND PUMP IT AT 120LBS. WITH A 1.25" TIP.HITS IT HARD AND FAST WITH LIMITED MANPOWER(4 MAN SHIFTS.)
500 GALLONS WILL GO A LONG WAY IF USED RIGHT.AND PAUL WE PUT OUR 1 3/4" UNDER A FLOW METER WITH THE 1"TIP FROM OUR 21/2" PLAYPIPE.HOWS 303GPM SOUND FOR A BLITZ LINE?
02-25-2000, 11:06 AM #12chiefjay4Firehouse.com Guest
An offensive-defensive attack?
Like the theory. Have one crew pull out the deck gun,2 1/2(smoothbore), or portable monitor, while the other stretches the 1 3/4" for a interoir mop up. Flow the big water for 30-60sec(enough to knock down the heavy fire),shut down the big water and quickly shift to the offensive with the 1- 3/4". You should also consider using PPV on the interoir attack.
It works well!!
02-29-2000, 08:47 AM #13STATIONTWOFirehouse.com Guest
Blitz=Apply large amounts of water for a short period of time in hopes of knocking the fire down to where an aggressive attack with smaller lines can be affective.If water is applied at 350 or more for 40 to 60 seconds and a knockdown is achieved,the total gallons applied will not usually exhaust the water tank.The blitz line should not be used for more then 1 minute, the objective is a short, powerfull delivery to the seat of the fire.
02-29-2000, 12:41 PM #14PLAYPIPEFirehouse.com Guest
Benson911, you hit it right on the head.
You can come ride with us anytime.
Needed: one pair of X-ray vision glasses to see through building walls (from the outside) to check for occupants.
Until I can get a pair, we're goin' in.
Nobody said this job was safe.
02-29-2000, 10:03 PM #15Lieutenant GonzoFirehouse.com Guest
I agree with Benson 911...you can't blitz if there are occupants in the house. Even if you opt for the blitz to protect an exposure, if you run out of water, the exposure is still threatened and your second due engine is still to far away, you've really "screwed the pooch"!
Take care and stay safe...Lt. Gonzo
[This message has been edited by Lieutenant Gonzo (edited February 29, 2000).]
02-29-2000, 11:32 PM #16STATIONTWOFirehouse.com Guest
JUST CAN'T COMPETE:
THE POST STATED WHAT DO YOU THINK ABOUT BLITZING ON TANK WATER.I THINK FOR THE MOST PART ITS A GOOD IDEA. WE PRACTICE IT. JUST ANOTHER TOOL IN ARE BAG OF GOODIES.ARE FIRST DUE HAS 1500 GALLONS.KNOCK THE SNOT OUT OF THE FIRE,VENT, SEARCH. I WILL GRANT YOU THAT IT WON'T WORK ON ALL, BUT WILL ON SOME.
[This message has been edited by STATIONTWO (edited March 01, 2000).]
03-01-2000, 01:06 PM #17T.D / 1122Firehouse.com Guest
One word describes this idea! "STUPID". Not a good idea at all unless you are prepared to write the structure off! Common guys think here.. what is going to be a better route? Say you do have 500 or 1000 gallons.. that amount will be better applied to the seat of the fire via 1 or 2 1 3/4 handlines. If the fire is that big then think of the amount of water that is actually penetrating into the fire! If you have an established water supply then that's different, but it's not so in this case. Like "Gonzo" said.. you better get it right should you try this because if you don't then you're gonna look pretty stupid standing there by a fire truck with your thumb up your a@#!
just my thought!
03-01-2000, 04:28 PM #18pete892Firehouse.com Guest
Years ago we modified a 500/500 pumper so that we could use a preconnect 2 1/2 in line.Currently our first out is a 50ft telesqurt with 1000 gal tank. 2- 2 1/2 precons plus the tower. Double piped out of the tank. Great knockdowns but SOP calls for the first 2 1/2 to get inside. Maybe we should call this a modified blitz. (Still knew at this computer stuff)
03-01-2000, 06:20 PM #19BIG PAULIEFirehouse.com Guest
STUPID is pretty harsh don't you think. Relax this is just a discussion. You asked the guys to think on this one. That is something you did not do . Did you read the opening statement. All It said was a fire. It did not say occupants or not it did not say fully involved or not. Just a fire. Lets give you a little more to think about. How about a fully involved two story 2000 sq. ft. home. fire blowing out of every orifice. If any one is home they are dead.
There is exposures on either side a hydrant 200' away and you are using 5" hose. Oh yea you have a 4 man crew. It sounds like you would hit the seat of the fire with one or two 1-3/4" handlines unknown gpm. Lets say 125 gpm each. With a structure fully involved there will be a very large seat, agree? With a 500 gallon booster tank you will be out of water in 2 minutes and I could just about gaurentee the fire will not be knocked down. To me this is wasting water. Now lets Blitz the snot out of this place. 500 gpm delivered to the seat of the fire as much as possible. Because of the many rooms in a house the seat is hard to completely reach. What do you think of a 25 second knockdown using roughly 250 gpm. This a true story. I did it. We used alot less water than if we would have tried to **** on it with 1-3/4".
I don't think any one would Blitz a fire that involved one or two rooms or when a saveable live was involved or at least I hope not.
03-01-2000, 06:50 PM #20BurlFirehouse.com Guest
250 gpm for 2 minutes will hurt the fire more than 100 gpm for 5 minutes. Big Fire= Big water
Engineer, Travis FD
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