The Apparatus Architect: Part 16

Tom Shand and Michael Wilbur continue their discussion on designing ladder company apparatus.

The next step is to look at the fire station that will house the new truck to insure that you have sufficient space in the bay, particularly the clear height of the bay doors for the new ladder truck. Most all manufactures produce aerial equipment with a variety of overall travel heights, ranging from just under 10 feet to over 121/2 feet.

The travel height of ladder trucks is dependent upon many things, including cab height, suspension and frame heights, body design and ground ladder packaging, as well as the height of the handrails on the ladder or tower sections. Remember that mid-mounted aerial devices tend to have a lower travel height than rear-mounted aerial devices. If height in your jurisdiction is a major concern (i.e., low underpasses), this fact may dictate a major portion of the apparatus design. Always verify the clear height of your door opening and any other obstructions that may limit the design of the new rig. In addition, be careful to look at the ramp and angle of departure to insure that the ladder truck will move in and out of the apparatus bay without restriction.

If possible, do not design the apparatus to fit the fire station, but design or renovate the fire station to fit the apparatus. Some fire departments become very shortsighted when it comes to this issue. They will spend huge sums of money for the ladder truck and spend nothing to house the vehicle. Then everyone in the department is mystified when apparatus mirrors, doors and tower ladder buckets are ripped off and left on the apparatus apron. You are just asking for trouble by trying to house a modern-day aerial device in a turn-of-the-century fire station originally designed for horse-drawn apparatus. Dollars spent today to properly house the vehicle could save thousands of dollars on unnecessary apparatus repair bills.

There has been a dramatic trend in apparatus design over the past few years to do more with less. In the world of ladder truck design the quint has become one of the most common aerial ladder devices as it allows departments to bring everything with them on one rig. We will cover some of the design considerations of quints in a future article; however, their popularity bears some discussion at this point.

Some of the positive aspects of the quints are: it increases your pump capacity, increases the total number of available ladder companies, provides multiple master streams and generally places the ladder truck in front of the fire building. However, there are drawbacks to the quint and some of these may significantly impact the operations of your department. First, to be effective on the fireground you must train all of your personnel to be proficient in both engine and truck operations. Second, the apparatus positioning for the quint will be different depending upon its intended use and depending upon the design of the apparatus, compartment space and ground ladder storage will be less than a non-quint unit.

Before your committee decides to place a fire pump, tank and hosebed on your next aerial device, make sure that you have carefully considered the overall impact with a larger piece of apparatus. Also, by adding a pump you have decreased compartment space, added thousands of dollars to the cost of the apparatus and may have increased the apparatus wheelbase, which will in turn affect the vehicle's maneuverability.

The size of your ladder truck in terms of wheelbase, overall length and jack spread will have a direct impact on the ability of the unit to set up and operate on the fireground. Just because the apparatus will fit into your station is no guarantee that the truck will maneuver and operate in the first-due area. Bigger is not always better; however, you need to insure that the apparatus is properly designed to carry the necessary tools, equipment and ground ladders to protect your district. The NFPA minimum requirements for a ladder truck include a 50-foot vertical reach, 250-pound tip load, 1,000-gpm waterway, 40 cubic feet of compartment space and 115 feet of ground ladders.