Fire Department, Pumpers, Tankers

Aerial Designers Manipulate Many Elements For Tight Spaces

Issue 9 and Volume 15.

Firefighters react as a burning three story house collapses in Paterson, NJ.
Firefighters react as a burning three-story house collapses in Paterson, N.J., on June 30, seeking cover behind Paterson Fire Department Ladder 1, a 2005 E-ONE 95-foot tower. Four people died in the early morning fire, and three were injured. (Fire Apparatus Photo by Michael J. Coppola)
A newark fire department aerial nests among a tree.
A Newark Fire Department aerial, splayed across a sidewalk, nests among a tree, van and a house to get positioned to reach the structure next door.
Delta fire uses a 100-foot smeal platform
Delta Fire in Delta Charter Township near Lansing, Mich., uses a 100-foot Smeal platform to douse a daytime apartment complex fire.
An E-ONE aerial is short-jacked in an alleyway.
An E-ONE aerial is short-jacked in an alleyway.

Squeezing aerials into tight spaces on the fire ground depends on a number of interrelated elements – the truck’s footprint, the length of its ladder, the maneuverability of the rig, the outrigger configuration and sometimes the ingenuity of the operator.

Manufacturers are helping firefighters solve the puzzle of placing aerials in narrow or seemingly-inaccessible spots by improving front wheel cramp angles, shortening wheelbases, reducing outrigger spreads and modifying platform profiles.

Joe Hedges, product manager for aerials at E-ONE Inc. in Ocala, Fla., said most truck makers look at three main areas when considering tight spaces – maneuverability, setting up the aerial and operating the aerial.

“First you have to get the truck there,” he said. “By increasing the cramp angle, you allow the truck to turn sharper and with the big front tires on aerials, 45 degrees is about the maximum cramp angle.”

Wheelbase is another key element affecting maneuverability. “With long cabs, big pump panels and tons of plumbing, the wheelbase grows,” Hedges said. “Wheelbases used to be in the 250- inch range, but now we’re getting out to 270 inches on dual rear axle trucks.”

Single-axle apparatus are typically more maneuverable than tandem-axle trucks. “The beams that hold the rear tires don’t pivot on a tandem, so there’s a different turning radius circle between the tire ahead and the tire behind, each taking a different path,” Hedges noted. “Both will scuff and leave marks on the road surface.”

Even E-ONE’s Bronto, which has a dual-axle rear on a 230-inch wheelbase with a 45-degree cramp angle, leaves tire marks when turned sharply, he said. “A short-wheelbase tandem unit is good for maneuverability,” he said, “but no matter who makes it, the tires will still scuff.”

Shorter Wheelbases

Most fire departments want shorter wheelbases so they can get into tight spots, he said. “They feel they can always replace tires.”

Tim Smits, national sales manager for Pierce Manufacturing Inc. in Appleton, Wis., agrees cramp angles are vital to truck maneuverability. “The difference between a 37-degree and a 45-degree cramp angle means a seven foot difference in turning radius,” he said.

Smits noted that 90 percent of Pierce’s trucks have a TAK-4 independent front suspension with a 45-degree cramp angle.

As for the wheelbase, he said, it depends on the vehicle and type of cab. “We try to shorten the wheelbase as much as possible, especially when building a quint,” he said. “We look at how to package the pump panel into a smaller space to shorten the wheelbase and with the 45-degree cramp angle, that makes it more maneuverable.”

If a fire department reduces the number of seating positions, Smits said a shorter cab can be fitted to a truck, perhaps 57 inches instead of 67 inches. “Take the shorter cab, the 45-degree cramp angle and a shorter pump house,” he said, “and you can make the truck very maneuverable, getting down to a 215-inch to 220-inch wheelbase.”

In quint configurations, he noted Pierce’s PUC configuration, with the pump under the cab, helps reduce the wheelbase.

Captain Mark Roche of the Newton (Mass.) Fire Department was on an apparatus committee that recently took delivery of a 2009 Pierce Arrow XD-100 rear-mount aerial with a fixed 500-gpm waterway.

“Pierce met our requirements of an 11-foot, 3-inch height for a heavy duty aerial because we have some firehouses that can’t accept today’s higher modern equipment,” Roche said.

Notching The Cab

Pierce’s solution, he noted, was to notch the cab to accept the ladder when it is stowed. “We have a 10-inch raised roof over the jump seat and the middle of the cab is notched approximately 4 inches deep for the width of the ladder,” he said.

The Newton Fire Department, which has 188 paid personnel, covers a population of 83,000 in an area of 18 square miles bordering Boston with six engine companies and three ladder companies operating out of six stations.

Roche said the department’s Pierce aerial has a front bumper reduced from 18 inches to 12 inches, a wheelbase of 215 inches, an overall length of 40 feet, 3 inches and a jack spread of 12 feet instead of the traditional 16 feet.

“We have no problem getting that truck into tight alleys and working it there,” he said. “The reduced jack spread makes a big difference on narrow New England streets.”

Paul Christiansen, marketing director for Ferrara Fire Apparatus Inc. in Holden, La., said his firm also offers a low-profile chassis for a rear-mount aerial that takes eight inches off the rig’s travel height.

“We can get a 77-foot aerial down to 10 feet, 9 inches, and a 102-foot ladder down to 10 feet, 10 inches,” he said. “We put a notch in the cab that enables us to bring the turntable down eight inches, which works for both a straight stick and a platform.”

Christiansen said the notched aerial doesn’t affect the handling of the vehicle or aerial operations.

The wheelbase can be shortened, he said, but often the overall length of the vehicle won’t change much because of the length of the ladder. However, he noted Ferrara was able to take four inches off the width of an aerial built for the Provincetown (Mass.) Fire Department to produce a narrower cab and body and reduced the wheelbase to 201 inches to meet special needs.

Provincetown, an old fishing village with narrow streets covering three square miles on the tip of Cape Cod, has many wooden structures, some touching each other on the waterfront pier. The fire department has 60 volunteer members.

Shortened Crew Cab

“Our entire fleet is custom designed,” said Provincetown Fire Chief Mike Trovato. “So we looked for a rear-mount ladder body not to exceed 96 inches [in width], a 200-inch wheelbase and an overall length of 34 feet.”

The result was a 77-foot Ferrara ladder with a shortened crew cab that can carry six, a 1,500-gpm Waterous pump, a 300-gallon water tank and a 10,000- watt generator.

The aerial uses H-type ladder jacks on the rear only, Trovato said, “because most of our terrain is pretty flat. If we had done front and rear jacks, it would have extended the truck an additional two feet, and we couldn’t afford that in terms of overall length.”

Jim Salmi, chief operating officer of Crimson Fire in Lancaster, Pa., said aerial manufacturers offer several outrigger configurations that can help firefighters get into tight places.

There is the traditional H-style outrigger, also known as the out-and-down, where a horizontal beam goes out and the jack goes down to the ground.

There’s also an under-slung style, Salmi said, where the outriggers are positioned underneath the truck.

Outriggers

Then there’s the A-frame or scissors style, where the outriggers are angled down at a fixed angle with no pivot to change their positional attitude.

Salmi said Crimson is currently designing trucks for Chicago, where the fire department faces tight spaces and confined areas of operation. “They’re leaning toward the A-frame jacks in the front, directly behind the cab and only a little wider than the truck so you can get out the door when the outriggers are out,” Salmi said. “The rear are under-slung style with a maximum width of 18 feet.”

If the truck is short jacked, he said, one outrigger would go straight down and the other out and down, which gives a very narrow footprint.

Salmi pointed out there are fire scene situations where the only good method to approach a fire is to operate in a very limited envelope over the front of the truck.

“For example, you might be in a tight street or alley with buildings on either side,” he said. “The primary range of operation would be toward the front of the vehicle. It would be hard to find enough area to rotate the ladder in a situation like that.”

He noted that departments can shrink the truck’s base to about 11-1/2 feet when the outriggers go out-and-down on one side and straight down on the other.

“Typically, that’s done with straight ladders, not platforms, and still gives you full stability,” he said. “If you look at the big cities that have tight streets and alleys – San Francisco, Boston, Washington, D.C. – largely they use ladders, a much higher ratio of ladders to platforms, mostly because ladders are a little simpler to operate and less costly.”

Pete Hoherchak, aerial product manager for KME Fire Apparatus in Nesquehoning, Pa., said KME designed a truck with a set of H-style outriggers at the rear and straight down outriggers behind the cab.

“In tight streets, you only have one side of the truck to consider, so you could set up between two parked cars and short jack the truck,” he said.

Hoherchak noted that all KME trucks have a rotation safety system that only allows operation of the ladder to the jacked side of the truck. KME also designs smaller platforms on its rearmount and mid-mount aerials.

The Bucket

“We don’t make a huge bucket, which is cumbersome to go around power lines, trees and poles and makes it difficult to get close to the building,” Hoherchak said. “We mitered the corners of the bucket, which allows it to be positioned against the building even if the truck isn’t perpendicular to the building. And with the mitered corners, the wall-to-wall turning radius is smaller.”

Jeff Rhein, aerial director of Rosenbauer in Lyons, S.D., said his firm mounts the turntable as far back as possible on the rear of the truck to allow for greater driver visibility. And with its platforms, Rosenbauer puts a walkway around the outside of the basket.

“That allows us a transition point,” said Rhein, “so the firefighter is not stepping blindly onto a roof.”

Rosenbauer also uses electronic envelope control on its aerials. “Our smart technology allows us to set up trucks where we only need to extend the outriggers a foot to allow us to rotate to that side using envelope control,” Rhein said. “The technology allows us to rotate the ladder or platform to the short jacked side, with full operation with limited extension.”

If the aerial is getting near a point where it shouldn’t be operating, he said an alarm sounds and then a yellow light flashes. If maximum extension is reached, he said a red light flashes and operation stops until the ladder is pulled back and raised.

Positioning Between Cars

Ken Creese, director of sales and marketing for Sutphen Corp. in Amlin, Ohio, said his firm’s designs all lead to getting trucks into tight spaces. Sutphen trucks use two out-and-down H-type stabilizers at the vehicle’s mid-point.

“If you’re in a tight spot with cars on both sides,” Creese said, “you can position between cars and not be worried about having to set another set of stabilizers behind them, like you would if you had four stabilizers instead of two.”

Sutphen’s 75-foot aerial uses scissorsstyle jacks in the center of the truck that can spread 14 feet wide.

This year Sutphen introduced a fivesection aerial ladder on a 230-inch wheelbase that’s 43 feet long with an overall height of 10 feet. “It has a center of gravity of 40 inches off the ground at the middle of the truck,” Creese said, “which makes it maneuverable, even at higher speeds.”

Bryan Smeal, regional sales director of Smeal Fire Apparatus Co. in Snyder, Neb., noted his company makes straight wheelbase aerials and tractor-drawn aerials.

“Keeping the wheelbase as short as possible is the biggest driver in maneuverability, along with a good cramp angle,” said Smeal. “You’ll find the straight stick is more maneuverable than a platform because it’s a shorter vehicle and easier to turn.”

Smeal also makes platforms with beveled edges where doors are located. “We use a bifold door with two hinges,” he said. “So if the platform is up tight to the building, you still have the ability to get the door open and out of the way.”

The Daly City (Calif.) Fire Department recently took delivery of a 2010 Smeal 100-foot tractor drawn aerial (TDA). The department, part of North County Fire Authority, runs five Smeal pumpers out of five stations with about 60 paid employees and covers 7-1/2 square miles with a 140,000 population.

Daly City borders San Francisco on the south, and department Capt. Joe O’Brien said mobility was a key consideration because of the hilly terrain. “The angle of approach and departure is so much better with a tiller,” he said. “We’ve been able to take it down the narrowest streets and get it into the tightest spots we have in town.”

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