How New York Uses and Cares for 101 Metal Ladders

How New York Uses and Cares for 101 Metal Ladders

PART 3

BECAUSE OF THE VARIETY of makes and models of metal aerials now in service, the New York Fire Department has no one instruction manual that covers all. Instead the Division of Training under command of Assistant Chief James T. Ward has issued training bulletins that cover the field operation of each one. In addition, manufacturers provide an operating manual for each model they deliver to the department.

Given the proper care, metal aerial ladders are relatively trouble-free. There are some in New’ York which have been in regular service for 16 years and are still going strong. Key to this proper care lies in the manufacturers’ manuals. Technical Assistant Robert J. Ferris of the Division of Repairs and Transportation strongly recommends that operating personnel become familiar with them. Aside from technical data (provided for shop mechanics) they give considerable information on the everyday operation of the aerial. Daily care and maintenance, minor repairs, how to shift gears, proper placement and angling, safe loading and many others all come within the sphere of the manuals.

Maintenance in quarters

Metal aerials require the same care as all other apparatus. But additional care is required for the moving parts that make up the ladder assembly. This care involves mostly lubrication and inspection and is the responsibility of both the chauffeur and officer. Proper records are kept of all such activities. Although many of the moving parts are self-lubricating, there are some that are not and the operating manuals provide diagrams and instructions for servicing those grease cups or oil holes that require attention.

Since the hydraulic oil tank is the key to the whole operation it should be checked frequently. The apparatus leaves the factory with this tank properly filled and if there is no unusual leakage it should last for a year. However, if the supply drops below the figure recommended in the operating manual, it should be replenished. In any event, a complete change of oil should be made yearly and a drain plug is provided in the bottom of the tank for this purpose. In refilling, transmission oil of the type recommended by the manufacturer should only be used and the oil kept absolutely clean. Minor leaks that develop in fittings can be usually stopped by tightening the connections.

The hydraulic system should be checked frequently and regularly, particularly in units where the ladder receives little use. This can be accomplished by taking the ladder out of quarters and raising it. But in inclement weather, if the ceiling of the apparatus quarters permits, the bed can be raised a few feet and the extensions run out. On some makes there is a test valve but the operation of this valve should be generally left to mechanics.

Both the turntable and the fifth w’heel have grease fittings which require attention once or twice a year. The turntable should be rotated during this operation so that all parts of the ball race are lubricated. For the same reason the truck should be jackknifed in both directions while greasing the fifth wheel. There are other grease fittings and oil holes on all makes but these vary from manufacturer to manufacturer and can only be determined by consulting the appropriate manual.

Inspection important

The ladder should be taken out of quarters frequently, raised and fully extended, and then carefully examined rung by rung. Ladder rollers can develop flat spots, generally from not turning because of lack of cleaning and lubrication. If unnoticed, such flattened rollers can cause serious damage to the affected section. Pulleys and cables should also be examined. If needed, all should receive an application of light engine oil.

As required, but at least every six months, the ladder slides should be lubricated with a thin film of waterresistant grease. Before this grease is applied, the ladder should be extended, and the old grease and grime washed off with a solvent. During freezing weather, a more liberal application of grease should be applied to retard ice accumulation.

Bolts that hold the turntable to the platform present another and most critical inspection point. On some makes they have a tendency to work loose and must therefore be checked regularly and tightened if needed. Ignored, they present the possibility of collapse, with destruction of the ladder and death or injury to fire fighters.

Operating precautions

In the field, the greatest care should be taken to see to the ladder’s stability. When placed for operation the aerial should be on as level a surface as possible. If the truck must be positioned on a grade that causes it to tip sidewise, the angle of the ladder, extension and loading must be reduced.

Loading is always a problem. The question comes up: “How many men and how much equipment should be allowed on a ladder at the same time?”

Many variables are involved in the answer to this question. Such variables include the size of the ladder, the degree of elevation, extension of the sections, and whether or not the ladder is unsupported (in cantilever) among others. And the answers can only be found in the manual relating to the particular make and model.

Generally, with the ladder in cantilever there is no need for any men to be on it. But within limitations of angle and extension there may be one man at the top and one half way up. At other times 12 men are permitted on the ladder, and on still others only three—it all depends on the design characteristics and will be stated in the operating manual.

Icing also presents a problem in loading. An accumulation of ice on a ladder can throw all calculations off and might render the ladder unusable. The added weight could be tremendous, particularly in a ladder pipe operation in bitter weather. However, icing presents its biggest problem when it comes time to bed the ladder and return to quarters.

Lubrication points on Mack-Maxim aerial. Other makes and models are similar

A heavy layer of grease as mentioned above helps prevent ice accumulation that binds sections in the slides. But when this fails, other methods must be resorted to. Steam from a thawing apparatus is probably the best method of freeing a frozen ladder, but this is a long drawn-out operation. Another method is to wash down the stuck parts with water from a hose, which water is, of course, above the freezing point and might melt the ice. However this method will only work when the air temperature is only several degrees below freezing and not in real bitter weather. As a last resort the ladder is bedded, if possible, with the sections till extended and the apparatus taken back to quarters to thaw.

Some apparatus come equipped with a de-icing valve as mentioned in Part 1. Operation of such valve permits working pressure to go as high as 1,000 psi or more, and in effect bypasses the relief valve. It should be used with extreme care. Often when the sections are thought to be bound, the problem lies with frozen ladder locks. The ladder-lock control might be in the off position, but the locks themselves are still engaged because of ice. This situation can be generally relieved by having a man ascend the ladder, free the locks and tie them back with a piece of wire if they won’t remain in the off position.

Another precaution to be taken involves the use of operating levers on the pedestal. These levers actually operate a solenoid which, in turn, controls the throttle and hence the pressure in pounds per square inch that is transmitted to moving part selected. Mr. Ferris has observed a tendency by some chauffeurs to feather or baby the controls in an attempt to move the designated part more slowly. He cautions against this since it can result in burnt-out switches.

Should the accelerating solenoid become inoperative for this or any other reason, set hand throttle at 900 rpm to position ladder and when this is done, lower rpm to idle. Chauffeurs should keep a constant eye on pressure and rpm and if either exceeds 1,050 while operating, a mechanic must be called.

Safety in operations

Both the Division of Training and the Division of Repairs and Transportation call for extreme care by personnel using metal aerials. Pressures developed by the hydraulic machinery can snap a man’s arm off or crush his body with the greatest of ease.

For this reason, no one is permitted on a metal aerial while it is being raised from the bed nor while the sections are extending. Occasionally, conditions may warrant a man remaining on a ladder while it rotates, but the operator must make absolutely sure that the ladder locks are engaged. He must also disengage the power take-off and rotate the turntable by the hand crank. As mentioned before, this prevents any possible jerking motions that would endanger the man on the ladder or possibly damage the ladder itself.

Additional safety recommendations, as well as other points of operation too numerous to elaborate on in an article of this scope, can be found in the manufacturers’ manuals. Use them!

How New York Uses and Cares for 101 Metal Ladders

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How New York Uses and Cares for 101 Metal Ladders

Part 2

THERE ARE elaborate charts, diagrams and formulas for placing and raising an aerial ladder at a fire, but New York believes in keeping it simple. Captain Thomas R. Clements, instructor at the chauffeur school, teaches that the center of the turntable should be placed preferably, but not more than, 35 feet from the wall of a building. As can be seen from the accompanying graph, this method is almost foolproof. The wall acts as a barrier which prevents lowering and extending to a point where stability is threatened.

For ladder pipe operation the recommended ladder angle is 70°. At this angle the ladder will have more than adequate stability when the pipe is operated at maximum recommended height and/or extension. However, if the center of the turntable is positioned more than 35 feet from a building, the ladder can be retracted and lowered. The point to remember here is that in any ladder pipe operation, the tip of the ladder should be no more than 35 feet horizontally from the turntable.

Checking the angle

The greater the angle to the ground, the greater the strength and stability of the ladder, and the greater its vertical reach. An 85-foot ladder must be brought to at least an angle of 60° whenever it is fully extended, whether or not it is supported at the tip. And a 100-foot ladder must be at least at a 70° angle under the same conditions.

To guide the operator there is an inclinometer on all inetal aerials from which he can tell at a glance what angle the ladder has in relation to the horizontal. This inclinometer is invariably on the base of the bed ladder adjacent to the operating pedestal. On some apparatus it is coupled with an extension meter that indicates in feet the total extension of the ladder only; the distance from the turntable to ground must be added for total reach.

Manufacturers can provide other and more complex variations of this inclino-extension meter, but all are considered optional equipment. On most New York ladders there is only the inclinometer. However, the department does provide a method for determining the extension of the ladder. It is inexpensive but still adequate.

Wheel chocks and tormentors—a must for every operation—Courtesy American LaFranceNumerals, blown up by artist, are painted on surface of strut facing pedestal

Spaced along the struts on the beam of the bed ladder are numerals painted on the surface of the strut which faces the operator at the pedestal. When the ladder is extended, a reading can be taken by lining up the lowest rung of the first sliding section with the marked strut on the bed ladder. The numerals are calibrated in feet for the maximum vertical extension of the ladder assembly from the ground. To determine extension of the ladder only, subtract distance in feet from the turntable to the ground.

Operations in cab

Operating manuals supplied by manufacturers always recommend that an aerial truck be jackknifed to provide maximum stability when raised. But in a city with cars parked on both sides of relatively narrow streets this action is a practical impossibility. It would also have the effect of blocking off the street to other apparatus.

Chauffeurs therefore are taught that the first step on pulling up to a fire building is to stop the truck parallel to the building with the center of the turntable 35 feet from the building and in line with the objective (window, roof, etc.). Next step is to put transmission in neutral, apply parking and air brakes, and set spring stabilizing control if provided.

Final operations in the cab call for engaging the power take-off which is controlled by a cable connected to a rod that extends through the dashboard or the floor. Either way, depress clutch pedal and pull out. Then release clutch slowly. If the power take-off does not readily engage, the gears are probably butting. Depress clutch, return control to its original position and repeat operation. Power take-off rod also automatically disengages the holddown lock on the bed ladder.

Stability most important

The next step in putting an aerial to work is to see to its stability. While this is the responsibility of the chauffeur and officer, it may be delegated simultaneously to other members of the company. First thing in this phase of the operations is to chock the rear wheels of the tractor to guarantee immobility of the apparatus. Then set tormentors. Division of Training insists that on all makes and models of aerials the tormentors on both sides of the apparatus be extended and set each time the aerial is raised. If footing pads are provided, place them under the base of the tormentors.

When the apparatus is not positioned on a firm roadway such as concrete, large planking—3 by 8’s or better—should be placed under the tormentors or footing pads. Softening of an earth or cinder roadway can be anticipated, particularly from water if the ladder pipe is used.

Failure to properly set tormentors can also result in distortion and weakening of the trailer frame in the area of the fifth wheel. This action in turn could bind the turntable sufficiently enough to cause the relief valve to operate.

At the pedestal

With the apparatus properly positioned and supported, the chauffeur mounts to the operating pedestal. Captain Clements teaches that the sequence of operation is to raise, rotate and extend. Preferably each step should be done separately, but the ladder may be rotated and extended at the same time under extreme emergency conditions. However, great care should be used to rotate the ladder smoothly since the stresses set up by jerking motions are most severe.

Once at the pedestal the chauffeur grasps the raising lever, moving it forward or toward him as the case may be, to raise the ladder assembly from the bed. Occasionally the ladder will bow, indicating power is being applied, but it will not release because the hold-down lock has not functioned. The chauffeur should then return the control handle to neutral and try again —almost always successfully unless the lock is seriously defective.

The bed is then raised, stopped at an angle greater than the final desired angle, and rotated until the rungs are parallel to the wall of fire building. In rotating, the chauffeur should be careful not to strike the side (beam) of the ladder against any obstruction. Metal ladders, in fact all ladders, are least able to withstand a lateral force. Finally, the chauffeur aims the ladder at the objective, reducing the angle of the bed as necessary and extends fly.

For example: Assume that his objective is the sill of a standard doublehung window on the fifth floor of a building. He sights along the beam of the ladder, much as one sights a rifle, aiming not for the sill, but for a point approximately halfway up the window. He then extends the fly to meet this point in so far as possible considering his distance from the objective. Next he lowers the ladder into the sill, making final adjustments as required to line up the locks and rungs. His efficiency in this operation will be greatly aided by the officer or other member standing adjacent to the wall of the fire building and beneath the tip of the ladder, and acting as guide particularly in the final adjustments. As stated in Part 1, the ladder locks must be engaged or at least in the “on” position before ladder is used.

It must be remembered that when the ladder is finally placed it should be in cantilever position (unsup for AUGUST, 1964 ported) about 2 to 6 inches out from the sill. This requirement prevails because when men mount the ladder it will give with their weight and drift into the sill to rest lightly on it. In this way the ladder is under both tension and compression forces that are in reasonable equilibrium.

Remember, too, that the tips of both beams of the ladder should rest equally on the sill or other objective. If one tip is left unsupported, the other will carry all the forces and the ladder will have a tendency to twist. As with lateral force, it is just not designed to withstand this type of stress.

To complete the raising operation, chauffeur locks turntable, and the bed raising lock if provided. Should he leave the turntable, or if ladder will be in use for any length of time, the power take-off must be disengaged, for the sake of safety.

Bedding the aerial is simply the reverse of placing it, with the exception that the ladder is first brought out from the building before ladder locks are disengaged and sections retracted.