Preconnected Line Drills With Attack, Supply Engines

Preconnected Line Drills With Attack, Supply Engines


The Volunteers Cornel

The effectiveness of an initial fire attack with a preconnected line is recognized by more and more fire departments and as a result, more than one size preconnected line is being carried on pumpers. If you are already using 1 1/2-inch preconnected lines, the milder weather throughout the country makes this a good time to sharpen up your evolutions with these lines and experiment with the use of 2 1/2-inch and larger preconnected lines.

The use of preconnected lines calls for the use of two engines. The first-in engine goes directly to the fire and starts the initial attack with water from its booster tank. The second engine then is responsible for supplying water to the first pumper. This is done by stretching lines and hooking up to a hydrant or drafting.

In most departments, this means the use of two engine companies—one for the initial attack and the other for water supply. However, this is actually a two-piece engine company evolution in which both the hose wagon and the pumper are pumpers.

Time factor: When training companies in the use of preconnected lines, you can complete more evolutions in a given time if you keep the hose lays short. The less hose you stretch, the more time you will save to devote to more evolutions. But to keep reality in the training, the actual time from the start of the evolution until water is supplied to the first pumper by the second pumper should be the same as it commonly is on the fireground.

When an engine is laying hose, it should not be moving faster than 10 to 15 mph. For drill purposes, let’s settle on 10 mph, which means that the engine is moving at the rate of 880 feet per minute. For convenience, let’s say that an engine will lay out 800 feet of hose a minute.

Working with these figures, you can simulate any fireground situation by stretching hose for a distance of no more than 200 feet, laying out 200 feet of hose in a single line or 400 feet in parallel lines. If you wish to simulate an 800-foot lay, use a watch to start the time when the second engine starts laying out. If it travels 150 to 200 feet to a hydrant, have everyone remain on the apparatus until a minute has passed. Then let them proceed with the hydrant hookup.

For a 400-foot or 1200-foot stretch to a hydrant, require half a minute or 1½ minutes for the hose stretch before hooking up. Times can be varied for other distances, of course.

Booster tank capacity: The first engine in this evolution charges its preconnected line as rapidly as possible and is applying water during the hose stretch and hydrant hookup by the second engine. How much time is available for the second engine to get water to the first engine will depend on the flow through the preconnected line and the size of the booster tank on the first engine.

With a 50-gpm, 1 1/2-inch line and a 500-gallon booster tank, the first engine will not need additional water for about 10 minutes. Remember, if the pumper is headed uphill, all the booster tank water will not drop into the pump. Now, what happens if you use a 100-gpm nozzle on the 1 1/2-inch line, or a 200-gpm fog nozzle (equivalent to a 1-inch tip) on a 2 1/2-inch line? Simple arithmetic shows that the booster tank water time will be reduced to 5 minutes for the 1 1/2-inch line or 2 1/2 minutes for the 2 1/2-inch line.

Develop your own drills: You should plan the training evolutions in accordance with the sizes of your booster tanks and the flows through your preconnected lines. With 800gallon or larger booster tanks, you might wish to try using a deluge set mounted on a pumper for the initial attack. Or you can use 100 feet of 3 1/2-inch preconnected hose with a 500-gpm fog nozzle. These large gallonages get you into the blitz attack area, which is something to think about.

To vary the hose stretch and simulate the first engine going down a long driveway to the fire, have the first engine drop a few lengths of hose and have the second engine pick up the lay and stretch to a hydrant. This time, also apply the time interval to the first engine to simulate laying out hose down 200 to 500 feet or longer driveways or farm lanes.

You can also vary the number of men on each engine. Try using one or two men on the pumper that goes to the hydrant. You can also do this for a drafting situation. Then change the engine assignments so that each engine company becomes familiar with both the attack and supply operations.

To complete the basic evolution, stretch a backup 2 1/2-inch line from the first engine. By the time this is done, this engine should have water from the source pumper.

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