A Closer Look at a New Chassis

The first thing that you notice is a “different” look: the black and silver color scheme; “pug nose”; wide, flat windshield; round headlights; and long, narrow mirrors hanging down from the front cab corners. A closer look at the new Pierce Velocity chassis reveals a number of innovations designed to improve firefighter comfort and safety.

Pierce unveiled two new chassis designs at Fire-Rescue International in Dallas this past September. The Velocity is a more high-end product that offers higher horsepower engines and 10-person seating. The Impel is the baseline design, incorporating many of the advanced features of the Velocity for the more price-conscious purchaser, with mid-sized engines and seating for up to eight firefighters.


(1) The new Pierce Velocity chassis for 2007. (Photos by Ron Jeffers.)

When I first saw the front of the cab design, I searched my memory for where else I had seen a pumper that looked like this. I finally located a photo on-line of a 1983 Continental custom pumper. The resemblance was striking!


(2) Mirrors mounted at the forward cab corners provide a good field of vision with the driver looking forward.

In my article “Change in Emission Standards Set for 2007” (Fire Engineering, February 2006), I predicted that the redesigned engine configurations and critical routing of the exhaust systems would require wider and taller engine enclosures in the already cramped cabs, especially with engines in the higher horsepower range. With a cab reconfiguration a possibility, Pierce asked firefighters across the country what improvements they would like to see in a new chassis design. Five specific critical areas were identified and addressed:

  • Interior space.
  • Safety and visibility.
  • Storage and clutter management.
  • Seats.
  • Easier maintenance.

INTERIOR SPACE

With the 2007 compliant engine design, the choice was to have the engine enclosure protruding farther into the passenger compartment or to expand the width of the cab. Pierce opted to expand the cab from a typical width of 96 inches to 100 inches. Up until now, many manufacturers offered a 100-inch-wide body, but the cabs remained 96 inches. The 100-inch-wide cab might take some getting used to, especially in the Northeast, where old, narrow fire station doors are the norm. To reduce the overall width, Pierce incorporated the Federal Motor Vehicle Safety Standard (FMVSS)-111 compliant One-Eleven mirrors hanging down from the corners of the cab out in front of the Velocity. Pierce literature states that this reduces the overall width by as much as eight inches compared with conventional door-mounted mirrors. The Impel has standard door-mounted mirrors, with the One-Eleven mirrors available as an option.


(3) The wide door opening allows easy access to the cab.

The One-Eleven mirrors provide a good view of the sides of the rig as well as straight down in front. The driver can keep his eyes forward, watching the road and his mirrors without shifting his head from side to side. In addition, the person sitting in the right seat doesn’t obstruct the driver’s view. Having driven many trucks and being familiar with the old-style “West Coast” mirrors on the doors and the cowl-mounted forward mirrors, I thought that the new mirrors might obstruct the driver’s view of the oncoming traffic lane, especially at an intersection. After sitting in the driver’s seat, I see that it will just take some time for the driver to become accustomed to positioning himself to get the needed view.


(4) The cab floor extends out to the edge to eliminate a foot well in front of the outboard seating positions.

The doors on the cab and crew cab are wider and the floor is lower without recessed step wells in the rear, allowing firefighters to enter and exit more easily. In addition, firefighters riding in the outboard crew cab seating positions will not have to ride with their feet dangling down in the step well. Full-height doors are standard on the Velocity with the shorter “barrier-style” doors provided on the Impel. Larger and deeper handrails and door handles also assist in cab entry and exit.

The interior of the cab is quite spacious. Pierce moved the engine forward seven inches, which increases room for the rear occupants.

SAFETY AND VISIBILITY

For several years, Pierce has offered side roll protection in the form of side curtain air bags, seat lowering system, and seat belt pretensioner to hold the firefighter securely in his seat during a side roll. The company plans to install frontal air bag protection in both the Velocity and the Impel beginning in the spring of 2007.

A single, one-piece windshield gives a wide, unobstructed view of the road, almost like a wide screen television. The corners of the glass lack the wrap-around design, which might create some distortion in the corners.

Pierce provides three windshield-wiper arms to keep almost the whole windshield clear during inclement weather. The Pierce TAK-4 independent front suspension is standard in both chassis.

STORAGE AND CLUTTER MANAGEMENT

Storage of equipment in the apparatus cab has always been a challenge. Oftentimes, map binders, clipboards, and portable radios are haphazardly placed on the engine tunnel, resulting in a cluttered work space and safety issues in a collision. The addition of computers and mobile data terminals (MDTs) compounds the problem even further.


(5) Storage for accessories is integrated into the engine cover.

The Velocity has a molded console that provides space for binders, portable radios, and cup holders and a wide, flat work space for the officer. The area across the dashboard from the officer is flat, and there is a glove compartment, which has been missing from fire apparatus for many years.

SEATS AND EASY-TO-USE SEAT BELTS

In my opinion, among the most visible and welcome improvements are the Pierce PS6 seats. The seats are extremely comfortable and well padded. While most seat backs are perpendicular to the cushion, the new seats have a 7 1/2 -degree angle of recline built in. This places the firefighter in a more natural seating position rather than being totally erect. The seats have self-leveling air suspension provided for comfort as well as an integral part of the side roll protection.

One of the biggest challenges, according to apparatus safety experts, is getting personnel to use seat belts whenever the apparatus is in motion. Personnel claim the seat belts are not long enough to easily wrap around them while wearing full gear and SCBA. Sliding the buckle up the belt and locating the mating end next to the seat is difficult at best. To address this, Pierce has provided a system with the male end of the buckle attached to two belts with independent rollers at the waist and shoulder levels. Even with my rather large frame in the seat, it was easy to grasp the belt end, draw the seat belt across the body, and plug it in to the easy-to-locate female receiver. Seat belt usage, or lack thereof, is monitored as part of the built-in chassis electronic package.


(6) Dual seat belts and retractors make attaching the seat belt easier.

Another issue the NFPA Apparatus Committee is examining is the mounting of SCBA in cab seats. The standard did away with the old-style spring steel clamps that would easily allow the SCBA to be launched into the cab in a collision. It now states that the SCBA must be mounted with a positive latching mechanical means to hold the device in its stowed position. This requirement resulted in a number of different designs of clamps and straps, all of which required the user to activate a release mechanism. This caused concern with many firefighters who were buckling their coats, attaching SCBA straps, attaching seat belts, and releasing the SCBA holding device while en route to a fire. The problem of retaining SCBA units in the cab became so apparent that some advocated taking them out altogether. (I think this is a mistake, as it would just lead to SCBAs on the floor of the cab without any type of restraint!)


(7) Inertia-activated clamp allows easy removal and replacement of the SCBA but will secure the cylinder in a collision.

Pierce, in conjunction with Lifeguard Technologies, has addressed this problem with an inertia-activated, hands-free SCBA bracket. The seat bracket has a clamping device that the SCBA cylinder snaps into and out of without any type of release mechanism, similar to the old spring clamp. The difference is that the inertia mechanism locks the cylinder in place during a collision. It acts much like the shoulder seat belt in your car, where it allows routine movements but locks up when violently pulled.

EASIER MAINTENANCE

Several features to improve apparatus maintenance have been incorporated into the new chassis. The front hood opens for access to some of the maintenance items and all of the windshield wiper components. An interior maintenance compartment in the rear of the engine enclosure allows access for checking and filling fluids (like most other chassis).


(8) The hood under the windshield opens to allow access for maintenance without tilting the cab.

Wire raceways with removable panels have been built into the cab to expedite tracing wiring harnesses for troubleshooting and repair. Circuit breakers and components are located behind a hinged panel on the officer’s side at floor level. In addition, a three-piece overhead console provides quick access to other electrical components.


(9) Wiring raceways are built into the cab to simplify troubleshooting. The cover on the demonstrator has a plastic viewing window to show this feature.

A big plus for the maintenance department is a lift/tow frame extension that can tow the vehicle without any special equipment. I have seen inexperienced tow operators damage the front of apparatus trying to lift the front of the rig by the bumper extension, which was never designed for such punishment.

A DIFFERENT CHASSIS DESIGN

I have covered many of the significant design features. Many more features and improvements that are a departure from the standard Pierce product line have been incorporated into these chassis.

As Pierce representatives said at the unveiling, “We take credit only for building it. All of the ideas came straight from firefighters.”

By the way, it does come in colors other than black with silver reflective flames on the sides!

William C. Peters retired after 28 years with the Jersey City (NJ) Fire Department, having served the past 17 years as battalion chief/supervisor of apparatus, with the responsibility of purchasing and maintaining the apparatus fleet. He served as a voting member of the NFPA 1901 apparatus committee for several years, representing apparatus users. He is the author of Fire Apparatus Purchasing Handbook (Fire Engineering, 1994); two chapters on apparatus in The Fire Chief’s Handbook, Fifth and Sixth Editions (Fire Engineering, 1995); and numerous apparatus-related articles. He is a member of the Fire Engineering editorial advisory board and of the FDIC Executive Advisory Board. He lectures extensively on apparatus purchase and safety issues. He can be reached at fireappwp@aol.com.

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