disc and drums, creating heat. Brakes are designed towithstand intense heat; however, brakes can fail fromexcessive heat if you try to slow down from a high speedtoo many times too quickly. Brakes fade (have lessstopping power) when they get hot and may not slowthe vehicle.The correct way to use your brakes for longdownhill grades is to go slow enough that fairly light useof the brakes prevents your speed from increasing.When you go slow, the brakes can cool down.Some operators think that backing off on the brakesfrom time to time (fanning) allows them to cool enoughto prevent overheating. Tests have proven this is nottrue. Brake drums cool slowly, so the amount of coolingbetween applications is not enough to prevent over-heating. This type of braking requires heavier brakepressure than steady application does. The heavierpressure used on the brakes builds up more heat than thelight continuous pressure does; therefore, select the rightgear, go slow, and maintain a lighter, steadier use of thebrakes.Escape RampsEscape ramps are constructed on most steepmountain grades. They are used to stop runawayvehicles safely without injury to drivers or passengers.Escape ramps use along bed of loose soft material, suchas pea gravel or sand, to slow a runaway vehicle.Sometimes, they are used in combination with anupgrade.VEHICLE RECOVERYRecovery is a major operation. During any recoveryoperation, always use a proven procedure. A haphazardapproach to a recovery problem or the use of atrial-and-error method can be a costly mistake. Such amistake can “deadline” the disabled vehicle longer thannecessary, cost valuable time, damage equipment, andinjure personnel. Self-recovery of vehicles, recoverywith wreckers, and recovery with like-vehicles arediscussed in this section.WRECKERSRecovery, using wrecker trucks, should beperformed by trained recovery personnel of Alfacompany or the transportation division. An under-standing of the ability of the vehicle to winch, lift, andtow is very important. For in-depth information, refer tothe operator’s manual that relates to the operation ofspecific equipment and their specific abilities.Mired TruckThe recovery of a mired truck using a wrecker truckis not always an easy task because it involves theresistance of the load, the approach to the load, and thedistance between the wrecker and the mired vehicle. Usea direct pull if the resistance created by the mired vehicleis less than the winch capacity of the wrecker.CAUTIONDo not hook the winch cable around thebumper on a vehicle. Wrapping the tow cablearound the bumper of a mired vehicle will resultin a bent bumper.An example of a simple winching operation isshown in figure 5-6. Some winching operations aremore difficult. The mired truck may have a resistancegreater than the winch capacity of the wrecker. Also, thewrecker may not be able to align itself with the truckdue to terrain. If so, use a 2:1 mechanical advantage anda change of direction pull, as shown in figure 5-7.Nosed TruckThe recovery of a nosed truck using a wrecker truckmay require only a towing operation. Some situationsmay require all three of the capabilities (winching,Figure 5-6.-Simple winch operation (direct pull).5-8
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