Ch 16. Inteoduction To Aerial Apparatus Flashcards
What are the three basic categories of Ariel Apparatus?
Ariel ladders, elevating platforms, and water towers
Per IFSTA, what are the three classifications of elevating platform Apparatus? (Refers to the design of the aerial device)
Aerial ladder platforms,
Telescoping aerial platforms,
Articulating aerial platforms
What types of chassis are found on Ariel ladders?
Aerial ladder devices may be mounted on a straight chassis in either a rear or midmount configuration, or on a tillered trailer.
How are the supporting beans of an aerial ladder constructed?
The supporting beams of the aerial ladder are of aerial ladder truss construction
What are the sections of an aerial ladder referred as?
Bed section and fly sections
What are the two most common materials for construction of Ariel ladders?
The two most common materials are heat treated aluminum alloy and steel
What are three ways that the fabricated structural members of an aerial ladder are fastened together?
The fabricated structural members may be fastened by rivets or may be welded or Heliarced (aluminum alloy)
What are the three main portions of an aerial ladder to which firefighters commonly refer?
Bed rails, top rails, and rungs. The base rails, are commonly called the beams. The top rails are commonly called handrails
Why are Ariel ladders designed and built with K bracing as a standard feature?
K bracing provides greater strength than older designs
What is the stabilizer on an aerial Apparatus?
Stabilizer is the device that transfers the center of gravity of an apparatus and prevents it from tipping as the aerial device, hydraulic lifting boom or A-frame is extended away from the centerline of the chassis. Also called outriggers
How are virtually all stabilizers or outriggers activated a new Ariel devices?
Hydraulic systems
What are the four main components of hydraulic systems?
Actuators
hydraulic fluid
hydraulic pump
hydraulic reservoir
What does a hydraulic actuator do?
The actuator transforms power into mechanical force
What is the medium by which the hydraulic actuator system transmits force?
Hydraulic fluid
In a hydraulic system how is force created on the hydraulic fluid?
Buy a hydraulic pump
How are hydraulic pumps powered on a Ariel Apparatus?
The pump is powered by a PTO arrangement of the vehicles main engine
What types of hydraulic pumps may be used in the hydraulic system?
The pumps used for the hydraulic system may be either load sensing piston pump, rotary vane pump or rotary gear positive displacement pumps
Hydraulic fluid is practically incompressible. In aerial apparatus the fluid may be under pressures of up to ________ psi?
3500
What part supplies or stores the hydraulic fluid in a hydraulic system?
The hydraulic fluid reservoir
Tubes and hoses supply hydraulic fluid throughout the system. What are these hoses typically made of?
Most manufacturers use steel tubing and aircraft tape, steel braided hose
What is the rating standard (strength rating) for steel tubing and aircraft type, steel braded hose?
Steel tubing and steel braided hose must be related to withstand pressures of at least 4x the normal operating pressures
The flow of hydraulic fluid through a system are regulated through a number of different _____________ that open or close to allow fluid movement.
Valves
What valves in a hydraulic system prevent fluid from flowing backwards through a component and act as a safety feature in the event that a leak develops in the system?
Check valves
What valves in a hydraulic system limit the pressure built up within the system?
Relief valves
What valves in a hydraulic system prevent unintentional or undesirable motion of the device from his established position?
Counterbalance valves
What important three-way valve directs fluid to either the stabilizer control valves or the aerial device control valves?
The selector valve a.k.a. the transfer or diverter valve
What unsafe action do selector valves prevent an aerial apparatus?
The selector valve prevents the stabilization and aerial device systems from operating at the same time. This system is governed by a microprocessor or other system
The hydraulic cylinders used for elevation and telescopic control of the aerial device are double acting. What does this allow?
Double acting cylinders are capable of receiving oil pressure from both sides of the piston so that force can be created in either direction
There are two rotary motor systems in Ariel apparatus. What do these rotary motors control?
One rotary motor rotates the aerial device through a ring opinion drive. The other rotary motor operates a winch drive to extend and retract the ladder.
What cylinders are used to operate stabilizers or outriggers?
Stabilizer cylinders
What type of cylinders are used to elevate the aerial device from its stowed position?
Hoisting cylinders a.k.a. elevating or lift cylinders
Hoisting cylinders are often constructed of what material to resist friction and where?
Chrome plating
In a hydraulic cylinder, what is the pivoting end of the piston rod that is connected to the anchor ear by the heel pin called?
Trunnion
Hoisting cylinders are attached to the aerial device or turntable by a ________?
Trunnion
What is the normal hydraulic pressure in the large pistons used in the lifting cylinders?
850 to 3000 psi
What do many new hoisting cylinders come equipped with that lock and hold the cylinder in the event of a leak or a blowout?
Integral safety valves
Many new apparatus are equipped with dual cylinders fitted on the base section used to extend what?
Used to extend the second section of the device.
What is the primary function of the turntable on an aerial ladder device?
The primary function of the turntable is to provide rotation to the aerial device
What are the normal fully extended length ranges, in feet on aerial ladders common in North America?
From 50 to 137 feet
What are the main uses of Ariel ladders?
The main uses of aerial ladders are rescue, ventilation, elevated master Stream application and gaining access to upper levels of an emergency scene
How is the working height for Ariel ladders measured?
The working height for aerial ladders is measured from the ground to the highest ladder rung with the ladder at maximum elevation and extension
What is an elevating platform?
A work platform attached to the end of an articulating or telescoping Ariel device
What is an aerial ladder platform
Power operated ladder, usually employing hydraulics with a passenger carrying device attached to the end of the ladder
What is a telescoping Ariel platform
And elevating platform equipped with piping systems and nozzles for elevated master stream operations. Telescoping Ariel devices are not meant to be climbed and are equipped with a small ladder for escape and emergencies
What is an articulating Ariel platform
An aerial device that consists of two or more booms that are attached with hinges and operate in a folding manner
What is the minimum required floor area for an aerial platform?
14 ft.²
What is the minimum height for the railing that must completely enclosed the floor area with no opening under the railing on a Ariel platform?
24 inches
What are the current standards for gates or doors on Ariel platforms?
Current standards call for Inward opening doors
What is the required height of a kick plate on an aerial platform floor?
4 inches
All elevating platforms are required to have two operator control stations. Where are the stations located?
One at street level and one in the platform. The controls at the street level must be able to override the platform controls. A back up hydraulic system is also required.
What must be built in to the underside of the aerial platform to protect firefighters?
A heat protective shield and a protective water fog curtain nozzle
NFPA 1901 requires a protective fog curtain nozzle on the bottom of the platform. How is this operated and what is the required minimum flow in gpm?
The nozzle is designed to be operated using a quick actuating lever on the floor.
The required Nozzle GPM is at least 75 GPM
What is the minimum load capacity on all elevating platforms when the area device is fully extended and without a charged waterway?
750 pounds
What is the minimum load capacity of an aerial platform if the water delivery system is charged?
500 pounds
What is the minimum flow requirements in gpm and psi for an aerial platform?
The water delivery system must be capable of discharging at least 1000 GPM at 100 psi in any position
Elevating platforms that are 110 feet or shorter should be able to be raised from the bedded position to the maximum elevation and extension and be rotated 90° in how many seconds or less?
150 seconds
There is no time requirement for platforms taller than 110 feet.
What type of accessory outlets are usually provided in the aerial platform?
Electrical, air, and hydraulic outlets
The working height of all types of elevating platforms is measured from the ground to top surface of the highest platform handrail when the aerial device is at maximum extension and elevation. What are the average range of Ariel platform heights?
85 to 110 feet
What is the primary difference between aerial ladder platforms and telescoping aerial platforms?
Aerial ladder platforms are designed with a large ladder that allows firefighters and victims to climb in either direction.
Telescoping aerial platforms are not intended for climbing. Generally they are equipped with a small ladder attached to the boom as a meeting for fire fire escape.
What are the two construction types of telescoping Ariel platform sections?
Box beam construction or tubular truss beam construction
What might be located inside the box beam construction of a telescoping Ariel platform?
Hydraulic lines, airlines, electrical cords and waterways
What is a huck bolt?
A mechanically applied rivet used in the construction of some aerial devices. Huck bolts can only be removed by drilling.
What is a benefit of an articulating Ariel platform?
The articulating elbow like design allows the platform to go “up and over” and into areas that are not accessible with a straight line apparatus.
What is the standard height range of an articulating Ariel platform?
55 to 85 feet
What is an aerial water tower?
Water towers are telescoping or articulating Ariel devices who is primary function is to deploy elevated master streams
What are common heights of Ariel water towers?
50 to 130 feet
What are the maximum capable flows in gpm for a Ariel water tower?
1000 to 5000 GPM
What are the characteristics of a Quint?
Quint must have a fire pump, a water tank, supply and attack hoses, ground ladders, and aerial device or elevated platform
Typically how are the third fourth and fifth if present sections of the aerial device extended and retracted?
The third fourth and fifth sections of the Aerial device are extended and retracted by corrosion resistant cables with very high strength steel called “plow steel”and are resistant to abrasion
Aerials using a main cable drum to extend in retract the area device maybe powered by one of what three means?
The main cable drum can be power mechanically, hydraulically, or electrically
What is the function of a turntable on an aerial device?
Its primary function is to provide continuous rotation on a horizontal plane
How many control levers are on most aerial control pedestals?
- Elevation
rotation
extension
What is an aerial/stabilizer interlock?
Prevents Ariel device function unless stabilizers are fully deployed
What is a body collision interlock
Does not allow ladder to move into regions where it would make contact with the body or cab
What is a rotation (shortjack) interlock?
Does not allow Ariel device to rotate over the side of the Apparatus where the stabilizers are not fully extended
What is maximum elevation slow down interlock?
The device will slow down before reaching maximum elevation or extension
What is the retraction interlock?
Device that prevents complete retraction without activation of the override function
What is the nozzle Stowe interlock?
A device that will not allow the ladder to cradle if the master stream nozzle is not properly position
What is an aerial function interlock?
Device that will not allow the aerial device to operate until the parking brakes have been set and the transmission has been placed in neutral or in the drive position with the driveline to rear axle disengaged
What is a cab interlock?
A device that will not allow the cab to raise if the engine is running
What is the tiller operator interlock
A device that will not allow the engine starter to work unless the tiller operator is seated and belted or a tiller cab start button is engaged
What is a bed ladder pipe?
A section of pipe, usually three or 3 1/2 inches, attached to the underside of the bed. Bed ladder pipes are usually equipped with solid stream nozzles because their inability to telescope prevents a effective fog stream application
What is the minimum internal diameter of a telescoping water pipe?
4 inches
Most telescoping water systems are capable of flows up to 1000 GPM
Portable waterways allow for a master stream to be pinned along to locations. What must be done before a master stream can be unpinned and moved?
The ladder must be fully retracted and the waterway uncharged before the operator adjusts the pin locations
What components are needed for a detachable ladder piping system?
The latter pipe itself, fire hose, whole straps, and a Siamese appliance
Where are detachable ladder pipe systems designed to be clamped?
The ladder pipe is designed to be clamped on the top to rungs of the fly section. It is normally controlled at the tip of the ladder by a fire fighter.
What is the capable flow in GPM detachable ladder pipes?
750 GPM
What is torsional stress?
A twisting action or an applied force resulting in a rotational twist
Why must a detachable ladder pipe be placed evenly spaced in the center of the ladder?
Placing the ladder on either side of the center causes unnecessary torsional stress on the aerial ladder
What is the restricted sideways movement, in degrees, of the nozzle to prevent excessive torsional stress from nozzle reaction?
The nasal movement is restricted to about 15° to either side to prevent excessive torsional twist
What is the size of a discharge used for attaching additional hose lines equipped on most elevating platforms?
2 1/2 inch discharge
Some water towers are equipped with an optional piercing nozzle. What is the stream capable of flowing in gpm?
300 GPM
What is true about NFPA 1901 requirements for breathing air systems on Ariel devices?
NFPA does not require aerial devices to be equipped with breathing air systems. However the standard does contain requirements if they are chosen to be installed.
Aerial apparatus carry electrical power cords to power portable equipment. What is the max length recommended for a common electrical cords?
200 feet
What is a “pole” ladder?
A pole ladder is an extension ladder that is 40 feet in length and requires “stay poles or “tormentors” for stability and leverage during the raising of the ladder.
What is the minimum amount of overhaul equipment required on Ariel apparatus?
NFPA requires aerial apparatus to be equipped with multiple salvage covers and to scoop shovels to assist with salvage overhaul efforts
What is the maximum acceptable steering wheel FreePlay on a tiller system steering wheel?
10° in either direction
When should hydraulic fluid levels be checked?
Only when the stabilizers and Ariel device are all in their stowed position
What should we suspected if an aerial ladder using fully deployed stabilizers begins to lean to one side after a period of time?
A leak in the system should be suspected and repaired immediately
What is deadheading?
Operating a hydraulic pump without allowing flow through the system this generates tremendous heat and pressure and can damage components in
What is nondestructive testing
Method of testing metal objects that does not subject them to stress related damage
How often should nondestructive testing be conducted on Ariel Apparatus?
Nondestructive Testing is conducted every five years, after accidents, when the aerial device has been subjected to unusual stresses or loads, and following major repairs or overhauls.
Aerial apparatus service tests are conducted on at least a yearly basis. What components are inspected during this service test?
Stabilizers
torque box
aerial device
waterways
Most water towers that is designed so their fire streams may be deployed at a range of elevations starting from a few degrees below horizontal to nearly ________ degrees from the ground?
90°
What allows various sections of the aerial device to extend and retract without causing excessive wear on parts of the device that come in contact with each other during operation?
Slides and rollers
What may result in the insufficient lubrication of the permanently mounted coupling system attaching the trailer to the tractor power unit and a tractor drawn aerial?
Insufficient lubrication may cause the coupling system to bind creating difficulty in steering control
What is a loss control activity?
Salvage and overhaul
