AB BRAKE
The current standard freight car air brake
system. Also see AUTOMATIC AIR BRAKE.
AB CONTROL VALVE
The operating valve of the AB freight car air
brake. It controls the charging,
application and release of the brakes.
ABANDON
To give up. For example, when consignee or shipper
relinquishes or gives up damaged freight to carrier; vehicle left on the
highway, or disowns or disavows any knowledge of.
ABRASION
Abrasion is the rubbing or wearing away of a
surface. Abrasion may also refer to a mark left on a surface. (also see
brinelling.).
ABS
Antilock Braking System or Anti-Skid Braking System.
ABSOLUTE BLOCK
A block which a train is not permitted to enter
while it is occupied by another train.
ABSOLUTE ERROR
The actual numerical value of the error.
ABSOLUTE POLAR MEASUREMENTS
A point on drawing specified in terms of a radius
(distance) and angle (theta) from the drawing origin (0,0).
ABSOLUTE X, Y COORDINATES
A point on a drawing specified in terms of X- and
Y- offset from the drawing origin (0,0).
AC. GENERATOR
An electrical generator that generates voltage and
current by rotating a magnetic field across stationary conductors. Also called alternator, ft produces
alternating current and uses diodes to change the alternating current to direct
current. See DC. generator.
ACCELERATION
(A): The rate of change of velocity with time. A =
vf-vi/t FPS or MPS Acceleration may be either a positive value
(acceleration), or a negative value (deceleration).
ACCELERATION FACTOR
(fa): A
pure number indicating the acceleration of a vehicle.
ACCELERATION OF GRAVITY
(g): The
acceleration of a falling body due to the force of gravity (its weight); a
standard of comparison of acceleration; usually taken as 32.2 ft or 9.81 m sec
per sec.
ACCELERATION SCUFF
A scuff mark made when sufficient power is applied
to the driving wheels to make at least one of them spin on the roadway surface.
ACCELERATION SCUFF
A scuff mark made when sufficient power is supplied
to the driving wheels to make at least one of them.
ACCELERATION SKIDS
A skid mark made when sufficient power is applied
to the drive wheels to make at least one of them spin on the road surface.
ACCELERATION SWITCH
Dashboard switch that enables acceleration feature of the cruise control. ( Detroit )
ACCELERATOR
(or accelerator pedal): The accelerator is the foot pedal which controls the engine speed
and in turn the speed of a vehicle. accelerator pedal depresses accelerator to
increase engine speed.
ACCELERATOR PUMP
The small internal pump which is a part of the
carburetor. It applies additional fuel
to the engine when the accelerator pedal is depressed.
ACCELERATED HEEL POINT
The intersection of the plane of the accelerator
pedal and the top of the floor covering.
ACCENT STRIPES
Fine taped or painted lines applied in contrasting colors to the
finished body to accent certain lines and contours.
ACCEPTANCE RECEIPT
By the consignee of a shipment. That terminates the common carrier contract
for transportation.
ACCESSORIAL SERVICE
A service rendered by a carrier in addition to a
transportation service, such as stopping in transit to complete loading or to partially
unload. Also heating, storage, etc.
ACCESSORY WEIGHT
Is the combined weight (in excess of those standard
items which may be replaced) of automatic transmission power steering power brakes power
windows, power seats, radio ant heater to the extent that these items are
available as factory-installed equipment (whether installed or not.)
ACCIDENT
That occurrence in a sequence of events which
usually produces unintended injury, death, or property damage. An event that produces injury and/or damage. Involves a motor vehicle in transport, and
occurs on a trafficway or while the vehicle is still in motion after running
off the trafficway.
ACCIDENT ANALYSIS:
See cause analysis
ACCIDENT RATE
The rate of the frequency of accidents to the
frequency of some exposure measured such as vehicle miles traveled.
ACCIDENT RECONSTRUCTION
The effort to determine, from whatever information
is available, how the accident happened.
Reconstruction was formally referred to as determining
"behavioral" or "immediate" causes of an accident: level
four of traffic accident investigation.
ACCIDENT SCENE
See scene
ACCIDENT SITE
See site
ACCOMMODATIONS
The structural members which support and adapt the
ACRS module to the vehicle.
ACKERMAN STEER ANGLE
The angle whose tangent is the wheel base divided
by the radius of turn.
ACKERMAN STEER ANGLE GRADIENT
The rate of change of Ackerman steer angle with
respect to change in steady-state lateral acceleration on a level road at a
given trim and test conditions.
ACQUAINTANCE
Any person other than a driver, passenger, or
witness who is acquainted with people or vehicles connected to the accident or
knows the circumstances of the accident
ACRS
(Air Cushion Restraint System) A device to protect
an occupant during crashes by deploying and inflating an air cushion.
ACRS MODULE
An ACRS unit which includes the inflator, manifold,
diffuser and air cushions, but does not include the sensors, body
accommodations or trim cover.
ACTIVE CODE
The status of the diagnostic monitoring in the ECM. ( Detroit ) When a diagnostic code is recognized, the ECM turns on either the yellow (check engine) or red (stop engine) lamp on the dashboard. ( Detroit )
ACTIVE RESTRAINT
An occupant restraint system that requires some
action on the part of the user to make the system functional. (Manual Seat
Belts)
ACTUAL FRONT OF DASH
The vertical line tangent to the foremost normal
surface of the dash panel at the centerline of occupant.
ACTUATION
Cushion deployment caused by a valid vehicle crash
condition..
ACUTE ANGLE
An angle that is less than a right, 90-degree,
angle.
ADAPTER, ELECTRICAL
A device that allows a connection to be made
between two items of equipment having different types of connectors Most often used to connect electrical lines,
particularly a connection between the tractor and trailer, when one electrical
line has four prongs and the other six prongs.
ADAPTOR, SPEEDO
Ration mechanism to correct speedometer reading.
ADJUSTABLE AXLES
See sliding tandem.
ADVANCE MATERIAL
Any material run prior to first regular production
run for purpose of pilot, pre-production or line-fill requirements.
ADVANCE OF A SIGNAL
The side of the signal opposite to that from which
the indication is received.
"A" END OF CAR
The end opposite that on which the hand brake is
mounted.
AERODYNAMIC ANGLE OF ATTACK
Aerodynamic angle of attack is the angle between
the vehicle x-axis and the trace of the resultant air velocity vector on a
vertical plane containing the vehicle x-axis.
AERODYNAMIC FORCES
An aerodynamic force is a force on a vehicle caused
by the flow of air across the vehicle.
An aerodynamic force is also generated by the movement of a vehicle
through still air, since the equivalent effect could be produced by passing air
over the same vehicle at rest.
AERODYNAMIC SIDESLIP ANGLE
The angle between the traces on the vehicle x-y
plane of the vehicle x-axis and the resultant air velocity vector at some
specified point in the vehicle.
A-FRAME SUSPENSION
The A-Frame is a type of automotive suspension
which includes two control arms and a spring.
In one configuration the spring is between two arms. Another configuration places the springs
above the upper control arm.
AFTER-ACCIDENT SITUATION MAP
A scale drawing of the scene after a traffic
accident situation is established; a graphical summary of the results of an
accident without indication of any assumed events of the accident or other
inferential elements
AFTERBURNER
A combustor in which heat is added to the working
fluid after the last expansion stage (SAE J604c).
AFTERCOOLER
Device for cooling air after compression in
turbocharger.
AGENT
A person authorized to transact business for and in
the name of another. A driver becomes
an agent of the trucking company when signing for freight.
AGGREGATED SHIPMENTS
Several shipments from different shipper to one
consignee that are consolidated and treated as a single consignment.
AGITATOR BODY
Truck body designed and equipped to mix concrete in
transit.
AGREED VALUATION
Freight value mutually agreed upon by shipper and
carrier as a bests for transportation charges.
It also may represent an agreed maximum amount that can be recovered in
case loss or damage. agreed wet 0 t A weight set and agreed upon by carrier and
shipper as a basis for charges.
AIR BAG
An inflatable bag that is filled with a gas after
receiving an activation signal. The
inflated bag then cushions the occupant during an impact and provides ride down
to the occupants. An airbag is a
passive restraint system.
AIR BAG
ADI
AIR BAG
AECM
AIR BAG
AMS
AIR BAG
API
AIR BAG
Airbag
AIR BAG
Airbag
Module
AIR BAG
Airbag
System
AIR BAG
All
Fire Pulse
AIR BAG
ATD
AIR BAG
Augmented
Inflator
AIR BAG
Auto
Ignition Material
AIR BAG
Bag
AIR BAG
Bag
Fold
AIR BAG
Ballistic
Tank Test
AIR BAG
Ballistic
Test
AIR BAG
Barrier
Test Vehicle
AIR BAG
BioSID
AIR BAG
Bonfire
Test
AIR BAG
Booster/Enhancer
AIR BAG
Bridgewire
AIR BAG
Bridge
Element
AIR BAG
Burst
Disc
AIR BAG
Burst
Test
AIR BAG
Canister
AIR BAG
Chest
G
AIR BAG
Clock
Spring
AIR BAG
Combustion
Chamber
AIR BAG
Connector
AIR BAG
Cover
AIR BAG
Crash
Sensor
AIR BAG
Cushion
AIR BAG
DAB
AIR BAG
D
Shaft Sensor trigger
AIR BAG
DERM
AIR BAG
Deployment
AIR BAG
Deployment
AIR BAG
Diagnostic
Module
AIR BAG
Diffuser
(Inflator)
AIR BAG
Diffuser
(Module)
AIR BAG
Discriminating
Sensor
AIR BAG
Disk
AIR BAG
D.O.T.
AIR BAG
Dummy,
AIR BAG
Drop
Test
AIR BAG
Dual
Stage Inflator
AIR BAG
ECM
AIR BAG
ECS
Electronic Crash Sensor:
AIR BAG
ECU
AIR BAG
EMC
AIR BAG
EMI
AIR BAG
EMI
AIR BAG
EMS
AIR BAG
ESD
AIR BAG
Effluent
AIR BAG
Energy
Reserve Capacitor
AIR BAG
Eurobag
AIR BAG
EuroSID
AIR BAG
Facebag
AIR BAG
Femur
Load
AIR BAG
Ferrite
AIR BAG
Filter Assembly
AIR BAG
Gas Composition Tests
AIR BAG
Gas Generant
AIR BAG
Gas Generator
AIR BAG
Grain
AIR BAG
HIC Head Injury Criterion:
AIR BAG
Heat Shield
AIR BAG
Housing
AIR BAG
Housing, Inflator
AIR BAG
Hybrid Bag
AIR BAG
Hybrid Inflator
AIR BAG
Hydroburst
AIR BAG
IRS
AIR BAG
Igniter
AIR BAG
Igniter
AIR BAG
Ignition Material
AIR BAG
III
AIR BAG
Impact
AIR BAG
Inflatable Restraint System
AIR BAG
Inflator Assembly
AIR BAG
Initiator
AIR BAG
Inner Cover
AIR BAG
Knee Bag
AIR BAG
Knee Bolster
AIR BAG
Marginal
Indicia
AIR BAG
Minibag
AIR BAG
Module Assembly
AIR BAG
Module Deployment Test
AIR BAG
No Fire
AIR BAG
No Fire Pulse
AIR BAG
OOPO
AIR BAG
PAB
AIR BAG
Particulate Composition Tests
AIR BAG
Pellet
AIR BAG
Pill
AIR BAG
Porosity
AIR BAG
Primary Sensor
AIR BAG
Primer
AIR BAG
Propellant
AIR BAG
Protective Cover/Outer Cover
AIR BAG
RFI
AIR BAG
R.I.M/Scrim
AIR BAG
Reaction Can
AIR BAG
Readiness Indicator
AIR BAG
Recorder
AIR BAG
SAB
AIR BAG
SDM
AIR BAG
SID
AIR BAG
SIR
AIR BAG
SRS
AIR BAG
Safety
switch
AIR BAG
Safing
Sensor
AIR BAG
Screen
AIR BAG
Screen
Chamber
AIR BAG
Secondary
Sensor
AIR BAG
Shorting
Clip
AIR BAG
Sled
Test
AIR BAG
Squib
AIR BAG
Tablet
AIR BAG
Tank
Test
AIR BAG
Tear
Seam A
AIR BAG
Tethers
AIR BAG
Threshold,
Deployment
AIR BAG
Thruster
AIR BAG
Time
to First Pressure (TTFP)
AIR BAG
Torso
Bag
AIR BAG
Transfer
Cord
AIR BAG
VC
AIR BAG
VC
AIR BAG
Vents
AIR BAG
Wafer
AIR BAG
Windshield
Wire Protector
AIR BRAKE HOSE
The flexible connection between the brake pipes of
cars or locomotives.
AIR BRAKE SYSTEM
An air brake system is a braking system in which
air under pressure causes actuation of the brakes at the wheels.
AIR BRAKES
Brakes that utilize compressed air instead of
fluid.
AIR CLEANER
Device for cleaning and purifying air entering
engine. Also called air filter. There may be two, a primary and a secondary.
AIR CLEANER, DRY
Filter element made from dry material such as
paper, fabric or metal.
AIR CLEANER, WET
Air cleaned through oil bath filter.
AIR COMPRESSOR
Device to build up and maintain required air
pressure in the brake system reservoir.
AIR CUSHIONS
Inflatable cloth bags which protect vehicle
occupants by minimizing occupant movement and lessening occupant impact.
AIR FILTER
Same as air cleaner.
AIR FILTER RESTRICTION GAUGE
Registers the flow of air through the aft filter
element. Provides indication of
filter's obstruction by dirt and other materials which would restrict the flow
of air to the engine.
AIR GAUGE
An instrument which indicates the amount of air
pressure in the reservoirs or brake pipe.
AIR HOSE
See air lines.
AIR INTAKE DISTRIBUTING MANIFOLD
Distributes air to the various cylinders of the
engine and attaches to the cylinder heads at the intake ports.
AIR LINES
Used to carry compressed air from one part of the
brake system to another and from tractor to the trailer. One called the emergency or supply line and
is always charged with compressed air.
The other line is called the service or control line. When the air brake treadle valve is
depressed, flows from the supply reservoir through the service line and causes
the brakes to apply.
AIR PRESSURE GAUGE
Measures pressure of air in air tanks in psi. If the pressure drops below 60 psi., a low
pressure warning device (buzzer or light) will operate, indicating unsafe
vehicle. Sometimes there are two. The second gauge indicates pressure used
during braking.
AIR RESERVOIR
(trailer)
Storage tank for compressed air for the trailer brakes.
AIR RESERVOIR
Storage tank for compressed air.
AIR RESISTANCE
Air or wind resistance to moving vehicle.
AIR SLIDER
A cab-controlled sliding fifth wheel that can be
unlocked by air to be moved backward or forward. See sifting fifth wheel.
AIR SUSPENSION SYSTEM
Air suspension systems are used to support the body
of a vehicle and to keep it level. The
compressed air is usually supplied by an air compressor driven by the
engine. A governor to keep the pressure
within limits, an air tank, appropriate piping and valves, and some type of air
bellows or air spring make up the rest of the air suspension system.
AIR TAG
A tag axle that has two bellows-like air bags that,
when filled, force the tractor's rear axle harder against the ground for a
smoother ride and for weight distribution between the two axles of the tractor.
AIR-FUEL RATIO
The air-fuel ratio is the fraction that expresses
the weight of fuel divided by the weight of air in the combustible mixture fed
to an engine.
AIR-LIFT AXLE
An axle with an elevating device operated by aft
that enables the driver to regulate the amount of weight carried on that axle
by raising or lowering it.
AIR-OVER-HYDRAULIC BRAKE SYSTEM
An air-over-hydraulic brake system is a brake
system that uses compressed air to transmit a pressure from the driver control
to a hydraulic brake system which in turn actuates the service brakes.
AIR-RIDE SUSPENSION
(See Air Spring.):
An air spring is a device filled with pressurized air which acts in the
same manner as a conventional metal spring.
Such devices are common on some types of heavy duty vehicles. It is sometimes called an air-ride suspension. Air springs have also been used in some
automobiles.
AIS ( Abb. Injury Scale )
An integer scale developed to rate the severity of
trauma; the scales include 1 minor, 2
moderate, 3 serious, 4 severe, 5 critical, 6 maximum; currently
untreatable. The scale does not
explicitly denotes fatal injury. It was
developed by the American Association for Automotive Medicine.
Setup parameter to enable or disable the alarm output in the ProDriver ( Detroit )
ALCOHOL INVOLVEMENT
An accident is considered to have involved alcohol
in any level of blood alcohol detected in a test on one of the involved persons
(e.g., vehicle operator or pedestrian), or if the investigating officer
indicated that drinking was involved, whether there was a test for alcohol
(i.e., BAC) or not. This includes DWI
and DUI citations and "had been drinking" notation.
ALEMITE FITTING
Grease fitting.
ALERTOR
A device which detects the frequency of the
engineman's movements and initiates an air brake application when the required
frequency of such movement is not maintained.
See Deadman Control.
ALLEY
A street or highway intended to provide access to
the rear or side of lots or buildings in urban districts and not intended for
the purpose of through vehicular traffic;
RR (slang), A clear track for movement through a yard.
ALLOWANCE
(1) A sum granted as a reimbursement or repayment.
(2) A deduction from the gross weight or value of goods.
ALLOY STEEL
A steel to which any alloying element other than
carbon is added to strengthen physical properties.
ALTERNATING CURRENT
Electrical current that changes its direction of
flow many times a second and is used in a building, as opposed to direct
current as used on a vehicle.
ALTERNATOR
Generator producing alternating current.
ALUMINUM KILLED STEEL
(AK) Aluminum killed, cold reduced box annealed
last (also tempered in exposed grades) drawing quality sheet steel for parts
having an extremely severe draw.
A. M. A.
Automobile Manufacturers Association
AMBIENT
The conditions of the surrounding or background
medium, as ambient temperature or sound.
AMBIENT WIND VELOCITY
ambient wind angle is the angle between the X axis
of the earth-fixed axis system and the ambient wind velocity vector.
AMBIENT WIND VELOCITY
ambient wind velocity is the horizontal component
of the air mass velocity relative to the earth-fixed axis system in the
vicinity of the vehicle.
AMERICAN TRUCKING ASSOCIATIONS, INC.
(ATA) A
national federation of independent and autonomous state trucking associations,
each representing all classes and types of truck operation, and thirteen
independent and autonomous conferences, each of which represents a special
class or type of truck operation.
Headquarters location 1616 P Street, NOW., Washington, DC 20036.
AMMETER
Gauge for measuring amperes in electrical system.
AMNESIA
See Retrograde Amnesia.
AMPERE
Unit of measurement of flow of electrical current.
AMPLITUDE
Amplitude of displacement at a point in a vibrating
system is the largest value of displacement that the point attains with
reference to its equilibrium position.
AMPLITUDE RATIO
amplitude ratio (relative magnification
factor) The ratio of a forced vibration
amplitude to the static amplitude.
AMPMETER
An instrument that measures the amount of current
flowing in an electrical current.
ANALYSIS
A process of study and evaluation with the intended
result of reaching a decision.
ANGLE COCK
A two position valve located at both ends of the
brake pipe on locomotives, passenger and freight cars. When open, it allows the passage of air.
ANGLE COLLISION
A collision between two traffic units approaching
or separate roadways or other paths that intersect.
ANGLE OF APPROACH
The minimum
angle between ground line and a line tangent to the foremost end of the
car and through the front wheel ground contact point; also called ramp angle.
ANGLE OF DEPARTURE
Minimum
angle between ground line and a line tangent to the rear-most end of the
car through the rear wheel ground contact point; also called ramp angle.
ANGULAR ACCELERATION
(a): An unbalanced torque (t), acting on a body
of moment of inertia I, and
producing in the body an angular acceleration. T = I*a Torque, moment of inertia, and
angular acceleration are all computed
with respect to the same
axis. The angular
acceleration must be reported in
radians/seconds2.
ANGULAR IMPACT
An angular impact occurs when two vehicles collide
in such a manner that their respective directions of force are not parallel to
each other.
ANGULAR ORIENTATION
The
orientation of the vehicle axis system (x,y,z) with respect to the earth-fixed
axis system (X,Y,Z) is given by a sequence of three angular rotations. The following sequence of rotations (see
Note 6), starting from a condition in which the two wets of axis are initially
aligned, is defined to the be standard:(1)
A yaw rotation, about the aligned z and Z-axis.'-2 A pitch rotation, , about the vehicle y-axis.'-3
A roll rotation, , about the
vehicle x-axis.
ANGULAR VELOCITY
A measure of the change of rotation with respect to
time. Angular acceleration is the rate
change of angular velocity, usually measured in radians per second, or the
vector quantity expressing velocity of a point in the vehicle relative to the
earth-fixed axis system (X, Y, Z). The
following motion variables are components of this vector resolved with respect
to the moving vehicle axis system (x,y,z).
ANNEALING
The process of heating or cooling the metal for the
purpose of softening or removing stresses.
ANTHROPOMORPHIC
A test dummy representative of the size,, shape and weight of a
particular male or female statistical type.
ANTI-LOCK SYSTEM
An anti-lock system is a portion of the service
brake system that automatically controls the degree of rotational slip of one
or more road wheels of the vehicle during braking.
ANTI-LOCK WARNING
The anti-lock warning on a brake system is a
combined audible signal and light that informs the operator of locked brakes.
APCN
(Advanced Product Change Notice) applies only to
parts not yet released for production. See Product Change Notice (PCN).
(Chrysler derived.)
APE HANGARS
Term used for motorcycle handlebars that are at
shoulder height of the rider.
APEX
The point at which two sides of an angle meet or
cross.
API
American Petroleum Institute
"A" PILLAR
The foremost pillar in the upper side structure of
a vehicle. Successive pillars rearward are labeled "B", "C"
and, in station wagons, "D".
"A" POINT
The point at which the centerline of the torso
contacts the seat cushion. Obsolete as a measuring point. (See "H"
point).
APPLICATION PRESSURE AIR GAUGE
Gauge that indicates pressure being applied by
brakes during brake operation. See air
pressure gauge.
APPLIQUE
A decorative panel applied to a basic interior or
exterior panel. May be metal, plastic, or a combination with a bright, brushed,
textured or painted finish.
APPROACH SIGNAL
A fixed signal preceding an interlocking signal,
governing the approach to the interlocking.
APU
Authorized pickup.
APWCS
Advanced Program Weight Control System
ARC
Part of a curve, especially part of a circle,
between two points on the curve.
AREA OF IMPACT
(AOI) has several meanings. It may mean the area of initial contact
between a vehicle and an object on the highway. It may also mean the area at which two vehicles collide.
AREA OF REST
The final after impact position of a
collision-involved vehicle. The
position where a collision-involved vehicle ceases all motion following a
collision.
ARGENT FINISH
A silvery, aluminum-pigmented paint with
approximately the same color and luster as brushed or satin-finished chrome,
aluminum or steel.
ARMATURE
Metal I-beam frame and wheels with a wood structure
- and sometimes styrofoam - used as the base for a clay model and made
approximately 3" under the size of the proposed finished clay shape. (See
also clay buck.)
ARRIVAL NOTICE
A notice, furnished to consignee, of the arrival of
freight.
ARTICULATED
Having parts connected by joints. A tractor-trailer is an articulated vehicle.
ASBE
American Society of Body Engineers
ASPECT
The appearance of a fixed signal conveying an
indication.
ASPECT RATIO
Aspect ratio as applied to a tire is the ratio of
the tire section height to the section width.
ASSIGN
The transfer of property to an another, frequently
for the benefit of creditors.
ASSIGNED CAR
Car which has been assigned to a particular
industry or for use with a specific commodity.
ASSIGNEE
One to whom a right or property is transferred.
ASSIGNOR
One by whom a right or property is transferred to
another.
ASOS
Automated Surface Observation System, FAA
ASTM
American Society for Testing and Materials
ASTRAY FREIGHT
Freight bearing marks indicating origin and
destination, but separated from the waybill.
See over freight.
ASYMPTOTIC STABILITY
Asymptotic
stability exits at a prescribed trim if, any small temporary change in
disturbance or control input, the vehicle will approach the motion defined by
the trim.
AT CRASH
The period of time in a collision sequence from the
point of initial contact to point of separation.
ATMOSPHERICAL REFRACTION
The amount in angular measure, by which the
altitude of a celestial body in increased by the refraction of its light in the
earths atmosphere, being zero at the zenith and maximum at the horizon.
ATOMIZE
Breaking up fuel to mis-like form.
AT-SCENE INQUIRY
Questioning informants at the scene of a traffic
accident for the purpose of obtaining facts required for the official accident
report and such other information as may be readily be available.
AT-SCENE INVESTIGATION
Examine and recording results of the accident and
obtaining additional information at the scene of a traffic accident which may
not be available later and which supplements data obtained for the accident
report. The information is factual as
far as possible. Level 2 of Accident Investigation.
ATTITUDE CHANGES
An object changing its attitude, in contrast to changing
its position, can rotate in any and all of the three planes X, Y, and Z. Yaw is rotation in the X,Y plane. Pitch is rotation in the X,Z plane, and Roll
is rotation in the Y,Z plane.
ATTRIBUTE
Any inherent characteristic of a road, a vehicle,
or a person that affects the probability of a traffic accident.
ATV
All Terrain Vehicle. A three or four wheel motorcycle used primarily for off road
riding.
AUGMENTED INFLATOR
An ACRS inflator which supplements the stored gas
pressure by means of a pyrotechnic heater.
"A" UNIT
A Diesel unit equipped with a cab and operating
controls.
AUTO TRANSPORTER BODY
Truck or trailer body designed for the
transportation of vehicles.
AUTOMATIC AIR BRAKE
A braking system which draws air from the
atmosphere and stores it under pressure.
A reduction in brake pipe pressure, regardless of how it is made,
(bleeding of air by use of a valve, or by a brake in the train line)
automatically applies the brakes. An
increase in brake pipe pressure causes brakes to release.
AUTOMATIC BELTS
(Passive Seat Belts) Occupant restraint system
automatically applied to occupant to provide protection in case of impact or
severe movement of the vehicle.
AUTOMATIC BLOCK SIGNAL SYSTEM (ABS)
A block signal system within the use of each block
is governed by an automatic signal.
AUTOMATIC BLOCK SIGNALING
1), A system in which signals are operated
automatically by a train, a broken rail, an open switch, a car standing on a
turn out, fouling the main track, etc.
2), Railroad crossing flashers and gate operated automatically by the
approach of a train.
AUTOMOBILE CAR
A car specially designed for transporting
automobiles. It may be a type of a box
car or a type of flat car usually called an automobile rack car.
AUTOMOBILE PARTS CAR
A box car specially fitted for transportation of
automobile parts in racks without packing.
AUTOMOBILE RACK CAR
Flat car with steel racks for transporting fully
assembled automobiles. Racks have
either two or three levels, are equipped with tie down devices, and are
cushioned for vertical and horizontal shocks.
AUXILIARY RESERVOIR
A reservoir for storage of compressed air to
operate the brakes of each individual car, and supplied for the main reservoir
on the locomotive through the brake pipe.
AUXILIARY TRANSMISSION
A second transmission connected with the main
transmission to provide a wider range of speeds and gear ratios.
AVAILABLE PATH
The entire area in a trafficway in which a traffic
unit may maneuver without interfering with other traffic units. Available path is not the same as the road
space which a vehicle is legally entitled to travel.
AVERAGE ACCELERATION
Average acceleration is found by dividing the
change in velocity of an object by the
time that is required to gain that velocity, using compatible units.
AVERAGE AGREEMENT
An agreement made between an industry and the
railroad where by the industry is debited for the time cars are held for
loading or unloading beyond a certain period, and credited for the times cars
are released within that certain period.
Demurrage charges are assessed at the end of the month for any
outstanding debits
The calculated average operating load on the engine while it is not in idle mode. This quantity is valid for all three choices of idle mode definition. ( Detroit )
AVERAGE VEHICLE SPEED
Trip Distance divided by Trip Driving Time. ( Detroit )
AWOS
Automated Weather Observation System
AXIS
A straight line about which a body or a geometric
figure rotates or may be supposed to rotate.
AXLE
The axle of a vehicle is the shaft on which the
wheels are mounted. The axle point is
the midpoint of the ails on a semi-trailer having a single rear axle. The axle point of a tandem set is the point
midway between the midpoints of the two axles.
The axle point is used in the analysis of motion of the tractor-trailer
combination.
AXLE ELLIOT
Front axle having forged yokes into which the
steering knuckles rotate.
Axle fore-and-aft shake
Oscillatory motion of an axle which consists purely
of longitudinal displacement.
AXLE RATIO
Ratio of axle to drive line the number of turns of the drive line in
relation to one full turn of the drive wheels.
The higher the numerical ratio, the slower the road speed; The ratio between the rotational speed
(RMP) of the drive shaft and that of the driven wheel. Same Ratio as the gear reduction final
drive, which is determined by dividing the number of teeth on the ring gear by
the number of teeth on the pinion gear.
See gear ratio.
AXLE REVERSE ELLIOT
Front axle having forged ends that insert between
the bosses of the yoked steering knuckles.
AXLE SHAFT FLOATING
Shaft carries no vehicle loads but transmits
torque.
AXLE SHAFT SEMI-FLOATING
Shaft carries vehicle loads as well as torque.
AXLE SIDE SHAKE
Oscillatory motion of an axle which consists of
transverse displacement.
AXLE TEMPERATURE GAUGES
Indicate temperature of lubricant in drive axles.
AXLE WEIGHT
The amount of a rig's gross weight that rest on any
one axle.
AXLE WINDUP
Oscillatory motion of an axle about the horizontal
transverse axis through its center of gravity.
AXLE YAW
Oscillatory motion of an axle around the vertical
axis through its center of gravity.
AXLE, LIVE
Driven axle.
AXLE, PUSHER
Non-powered rear axle, located ahead of drive axle.
AXLE, TAG
Non-powered rear axle (not driven); follows drive
axle.
References
Detroit Diesel
Caterpillar User's Manual