P

 

 

P RELEASE

Production release pilot.

 

P.T.O.

Power take-off, used to transmit power from engine to auxiliary equipment.

 

PACKAGE

Concept of organization of vehicle including dimensions.

 

PACKAGE CAR

A car containing several less-than-car load shipments.

 

PACKAGE DRAWING

Guide for use by engineering and design functions in completion of design of total vehicle.

 

PACKAGE TRAY

The shelf-like portion of the interior between the top of the rear seat and the backlight.

 

PAD

Process Assembly Document

 

PALLET

A portable platform for holding material for storage or transportation.

 

PALLETIZED

Stacked on pallets.

 

PAN

Those panels which constitute the lower closure of the floor pan and rear compartment pan.

 

PANEL BODY

Small, fully enclosed truck body often used for small package delivery.

 

PANTOGRAPH

A device located on the top of electric equipment which collects power from an overhead contact wire by means of a sliding contact shoe.

 

PARALLEL CIRCUIT

A circuit in which all control and current consuming devices are arranged in several independent branches.  Each branch provides a separate current path through the circuit components on this branch only.  See series circuit.

 

PARALLEL HOP

parallel hop  is the form of wheel hop in which a pair of wheels hop in phase.

 

PARALLEL SPRINGING

Describes the suspension of a vehicle in which the effective static deflections of two ends are equal; that is, the spring center passes through the center of gravity of the spring mass.

 

PARTIAL IMPACT

An impact in which motion is continuous between the parts of colliding objects which are in contact with each other; sideswipe.  Compare with full impact.

 

PARTICIPATING CARRIER (tariff)

A railroad which is a party, under concurrence, to a tariff issued by another railroad or by a tariff publishing agent.

 

PASSENGER

Any Person in or on a vehicle involved in an accident other than the driver.

 

PASSENGER CAR

Any motor vehicle that is 1.) a convertible,   2.) a 2-door sedan,  3.) a 4-door sedan or hard top,    4.)a 3 or 5 door hatchback coupe,  5.) an automobile with a pick-up body, or 6.) a station wagon.

 

PASSIVE RESTRAINT

An occupant restraint system that does not require any action on the part of the user for its activation or use.

 

PATTERN

Model for making a mold in casting.

 

PAVEMENT

That part of a roadway having a constructed surface for the facilitation of vehicular traffic.

 

PAVEMENT GROOVING

Channels cut into the surface of a pavement for the purpose of drainage.  Usually placed in curves and aligned in the direction of travel.

 

PAWL (wheel brake)

A pivoted bar adapted to fall into the notches of teeth of a wheel as it rotates in one direction, and to restrain it from backward motion.  See ratchet and brake ratchet.

 

PCI DATE

Date of issuance of "Product Change Information" or "Release".

 

PCN

(Program Change Notification) A form that provides notice and a series of instruction for a product change. (Chrysler internal)

 

PCP

(Program Chassis Package) A "Concept" package which includes Basic Engineering Product Assumptions, Serviceability Objectives (including Seating), Instrument Panel, Controls, Heater, Air Conditioning, Ventilation, Safety Restriction, etc.

 

PCR

Product Change Request

 

PEAK DECELERATION

The maximum value of the passenger compartment deceleration in a crash.  This is normally some 20% to 50% greater than the mean deceleration.  This can also be important in assessing crash severity, particularly for restrained occupants.

 

PEAK LINE

An intersection of two planes, or a sharply defined ridge in a metal surface.

 

PEAK-TO-PEAK AMPLITUDE

Peak-to-peak amplitude of displacement at a point in a vibrating system is the sum of the extreme values of displacement in both directions from the equilibrium position.

 

PEDALCYCLE

A vehicle operated solely by pedals, and propelled by human power.

 

PEDESTRIAN

Any person afoot; any person not in or upon a motor vehicle or other road vehicle.

 

PEDESTRIAN IMPACT KINEMATICS

The motion of the pedestrian resulting from impact.

 

PERCENT DEFLECTION

The static deflection expressed as a percentage of the unloaded section height above the top of the rim flange.

 

PERCEPTION

The general process of detecting some object or situation and comprehending its significance.

 

PERCEPTION DELAY

A time from the point of possible perception to actual perception.

 

PERFORMANCE

The agree to which reaction corresponds to a decision relating to evasive tactics or driving strategy; how well the decision is executed.  Performance is not necessarily the success of reaction, because an excellent performance of a bad decision may have an unfortunate result.

 

PERIOD

Period of an oscillation is the smallest increment of time in which one complete sequence of variation in displacement occurs.

 
Periodic Maintenance

One of three configurable Periodic Maintenance parameters. ( Detroit )

PERIODIC VIBRATION

Periodic vibration exits in a system when recurring cycles take place in equal time intervals.

 

PERISHABLE

Commodities easily spoiled or damaged because of weather or delay in transit.  Usually describing food stuffs.

 

PERSPECTIVE GRID

A parallelogram (usually square or rectangle) of known size placed on a flat surface so as to appear in a photograph as a basis for locating marks or points which also show in the photograph of the surface.

 

PERT

Programmed Evaluation Review Technique

 

PF

(Performance Standard) Specification of performance  of a mechanical, electrical or other operating unit installed in a vehicle. (Chrysler derived)

 

PGM

Poly-Gel Mitigator

 

PHOTOGRAMMETRY

The use of photographs for map making.

 

Pi

Constant used in solving properties of a circle ( = 3.1416).

 

PIGGY BACK

The transportation of truck trailer and containers on railroad flat-cars.

 

PILLAR

A vehicle roof support structure.  The pillars between the windshield and the front seat side windows are the A pillars, those between the front and rear seats are the B pillars, and those at the back of the rear seats are the C pillars.  There are left and right A, B, and C.  The roof support structure at the back of a station wagon is the D pillar.

 

PILOT

An employee assigned to a train when the engine man or driver of a track car is not qualified on the physical characteristics or rules of the railroad.

 

PILOT PROGRAM

Initial program for tryout of new tooling and fixtures, engineering procedures, etc., plus the building of advance program bodies for show and engineering test, etc.

 

PINCH WELD  DLO

Window opening in the body formed by the raw edges of a pinch-weld.

 

PINK REPORT

A listing of all product problems accepted by Car Engineering for funding and timing.

 

PINTLE HOOK

Coupling device at rear of truck for the purpose of towing trailers.

 

PISTON

A device that moves up and down in the engine cylinder and provides power to the crankshaft.

 

PITCH

Rotation of a body about its lateral axis.

 

PITCH VELOCITY (q)

 The angular velocity about the y-axis.

 

PITCHING MOMENT COEFFICIENT

(C M y)  is based on the yawing moment deriving from the distribution of aerodynamic forces acting on the vehicle.

 

PITMAN ARM

The pit men arm of a steering system is a rod connected to the output shaft of the steering gearbox   As the pitman arm rotates through an arc, the end of the pitman arm, which is connected to the steering linkage, causes the steering linkage to move to the right or left.

 

PIVOT PIN (coupler)

Another name for the knuckle pin.  It is so called from the fact that the knuckle, when opening, swings about the pin as a pivot.  See coupler.

 

PK SETUP

Checking the fit-up of detail parts by assembling a complete body-in-white with screws or rivets.

 

PLACARD

Paper forms of various designs used to identify cars or trailers requiring special attention; eg. Hazardous cargos.

 

PLAN VIEW

A view looking down on the subject.

 

PLANETARY DRIVE

Gear reduction system with sun gear transmitting reduction through planetary gears to main output shaft.

 

PLATEAU

a surface extending above the normal sheet metal.

 

PLATFORM BODY

Truck or trailer body with a floor, but no sides or roof.

 

PLENUM CHAMBER

Ventilating duct in the front end of the body through which air flows from the outside to the inside of the body.

 

PLENUM-MOUNTED STEERING COLUMN

A steering column which is required for the driver's ACRS. This column is mounted entirely on the center duct reinforcement so as to be isolated from rearward movement of the dash panel (fire wall).

 

PLP's

Principal locating points for assembly fixtures.

 

PLUG DOOR

A door on refrigerator or box cars which is flush with side of car when closed.  To open, it is swung out and rolled to one side.  Also called sliding flush door.

 

PLUMBING

The pipes, hoses, fixtures and other apparatus concerned in the distribution and use of compressed air in the vehicle's brake system.

 

PLY

A ply is a layer of rubber-coated parallel cords in a tire.

 

PLY RATING

The term ply rating is used to identify a given tire with its maximum recommended load when used in a specific type of service   It is an index of strength and does not necessarily identify the number of cord plies in the tire

 

PLY SEPARATION

Ply separation is I parting of rubber compound between adjacent plies of  tire

 

PNEUMATIC TIMING

The time required for transmission of air to or from brake chambers upon brake actuation or release.

 

PNEUMATIC TIRE

A pneumatic tire is a mechanical device made of rubber, chemicals, fabric, and steel or other materials, which, when mounted on an automotive wheel provides the traction and contains the gas or fluid that sustains the load

 

POD

A streamlined compartment to house various mechanical implements; e.g., lights, dials, gauges, etc. It is usually round or elliptical.

 

POINT OF ACTUAL PERCEPTION

The point of actual perception is the point at which an object actually was detected and recognized as a potential hazard.

 

POINT OF NO ESCAPE

The place in time after or beyond which the accident cannot be prevented by a particular traffic unit.

 

POINT OF ORIGIN

The terminal as which a shipment is received by a transportation line from the shipper.

 

POINT OF POSSIBLE PERCEPTION UNDER EXISTING CONDITIONS

The point of possible perception under existing conditions is the point at which it would have been possible to detect an object under the conditions of weather, light, roadway, etc. , existing at the time the incident actually occurred

 

POINT OF POSSIBLE PERCEPTION UNDER NORMAL CONDITIONS

The point of possible perception under normal conditions is the point at which it would have been possible to detect an object in the absence of any unfavorable conditions of weathers light, roadway, etc.

 

POINT OF TANGENCY

The point on a curve where the tangent touches it; PT; on a roadway, usually the point where a curve begins or ends.

 

POINTS

Exact locations on a model, usually derived from a blueprint or from the model itself to duplicate the opposite side of the model.

 

POLARITY

Indicating positive or negative electrical system; positive polarity indicates positive ground and vice-versa.

 

POLE TRAILER

Trailer composed of a single telescopic pole, a tandem rear-wheel unit, and a coupling device used to join the trailer to a tractor.  Pole trailers are used to transport logs or similar items, when chained together becomes a rigid unit thereby serves as its own trailer body.  Pole trailers are adjustable in length,

 

POOL CAR

Specially equipped cars of different ownerships assigned to a specific company or location.

 

PORK CHOP

An extension of the instrument panel shape on the door, usually an integral part of the door garnish molding.

 

PORT OF ENTRY

A port at which foreign goods are admitted into the receiving country.

 

PORTLAND CEMENT CONCRETE

A concrete made with Portland cement.

 

PORTS

Apertures in engine block for the passage of gas or liquid.

 

POSITION CONTROL

That mode of vehicle control wherein inputs or restraints are placed upon the steering system in the form of displacements at some control point in the steering system (front wheels, Pitman arm, steering wheel), independent of the force required.

 

POST CRASH

The period of time in a collision sequence from the point of separation to the occurrence of the last event which significantly influences the vehicles or occupants of those vehicles.  The post crash period will usually extend beyond the cessation of motion.  Fire, tow out damage to vehicles, aggravation of injuries to occupants due to inappropriate medical care are examples of post crash events.

 

POST IMPACT

See post crash

 

POST-EVENT INFORMATION

Information acquired after the event is over, that can be integrated into the witness’ original memory for the event.

 

POST-HOC SIMPLIFICATION

When faced with a seemingly unrelated set of events, people will reconstruct the situation in such a way as to make the events be as internally consistent as possible.  Then they will remember whatever they need to add, in order to simplify the situation.

 

POSTURE ANGLE

Angle between the spine and the upper legs of a manikin in a sitting position.

 

POTENTIAL ENERGY

Potential energy is the energy possessed by a body by virtue of its being elevated above a certain datum.  It is expressed analytically as.  P.E. = Mgh

 

POWER

Power is the rate of doing work

 

POWER ASSIST STEERING

Power assist steering comprises the usual elements of a manual steering system (steering shaft, gearbox, steering linkage) plus, a hydraulically operated device to multiply the steering shaft torque so that the forces supplied by the hydraulic unit assist the operator in steering or turning the vehicle

 

POWER HOP

An oscillatory hopping motion of a single wheel or of a pair of wheels which occurs when tractive force is applied in forward or reverse motion of the vehicle.

Power Interrupt
The total duration of all power interrupts in HH:MM:SS duration format. This is the only time reported without seconds resolution. ( Detroit )

Power Interrupts
Number of times that power to the ProDriver was disrupted Detroit )

Power Interrupts
The engine hours at the start of the most recent power engine hour interrupt. ( Detroit )  

POWER STROKE

Phase of the four-stroke cycle when fuel is ignited and combustion takes place.

 

POWER TRAIN

The series of parts that transfer the power of the engine to the wheels.  Same as drive train.

 

POWERED AXLE

See drive axle, commonly called a live axle.

 

POWER-LIFT TAIL GATE

A power-operated tail gate capable of lifting load from street level to the level of the truck or trailer floor.

 

PPC

Product Planning Committee

 

PPI

(Pre-Production Part Index) Total number of characteristics within specification divided by the total number of characteristics checked. (Chrysler derived)

 

Ppk

(Preliminary Process Capability Index) is an index similar to  Cpk but based on data from early, short-term studies of new processes.

 

PPPI

(Preliminary Process Potential Index) is an index similar to Cp but based on data from early, short-term studies of new processes.

 

PPQR

(Priority Parts Quality Review) Chrysler program to review product design and manufacturing feasibility to produce a quality product.

 

PR/R

(Problem Reporting & Resolution, GP-5) is a generic process for GM to report and resolve problems between customers and suppliers.

 

PRE-CRASH

The period of time in the collision sequence from the first significant event associated to a cause of the collision to initial contact   A driver's medical history, mechanical work done on a vehicle, or driver's actions leading up to collision are examples of pre-crash events

 

PRE-IMPACT

(See Pre-Crash)

 

PRELIMINARY  PAR

Advanced working copy of a pilot action request from a pilot program for action on proposed change.

 

PRESSURE REGULATOR

(fuel} A bypass valve to regulate the pressure of the fuel supplied to the injectors.  By passed fuel flows back to the suction side of the gear pump.

 

PRE-TRIP INSPECTION

See inspection.

 

PRIMARY CAUSE

A misnomer loosely applied to the most obvious or easily explained factor in the cause of an accident or the most easily modified condition factor.

 

PRIMARY SAMPLING UNIT

A city, county, or group of contiguous cities or counties with an aggregate population of at least 50,000 which defines a geographic area for accident investigation.  PSU selection is the first stage in the probability sampling of accidents for NASS.

 

PRIMARY SHOES

Primary Shoes are the brake shoes in a drum brake system which are mounted on the brake plate in the front position   Each wheel has a primary (front) shoe and a secondary (back) shoe

 

PRINCIPLE DIRECTION OF FORCE

(PDOF) Refers to lines of force during the collision of vehicles

 

PRINT

An imprint of liquid or fine dust picked up by a tire or shoe sole at one place and left at another, usually showing the pattern of the tire or shoe that made it.

 

PRIVATE CAR

A car having other than railroad ownership.

 

PRIVATE SIDING

A side-track owned or leased by an individual or firm.

 

PRIVILEGED VEHICLE

In any situation, the vehicle which has the right-of-way over other vehicles under the law.  Also see burdened vehicle.

 

PRNDL

(Pronounced "prindle") The automatic transmission indicator dial made up of the initial letters of the words Park, Reverse, Neutral, Drive and Low.

 

PROBABLE ERROR

Probable error is the investigator's estimate of error in measurement which might be expected as a result of influences beyond his control

 

PRODUCT ACCEPTANCE SPECIFICATIONS

(PAS) These communicate design instruction s and requirements such as durability and reliability levels, performance factors, safety considerations, appearance (items not specified by "Styling"), package, and other appropriate "end-results" information required to design acceptable systems and components. The manner in which these requirements are met is not normally specified, but tests which are necessary to conform that requirements have been met should be defined. PAS are normally published in two sections:  1. General PAS (GPAS) which define requirements which are common to several vehicle lines.  2> PAS Exceptions (PASE), which define unique and specific requirements for a particular model year vehicle.  Together these two sections constitute the PAS for a given vehicle program.

 

PRODUCT OBJECTIVES

A consensus of what has been determined to be the most marketable product for a given model year; this identifies basic appearance, performance, cost objectives, etc.

 

PRODUCT PLANNING

Is the activity having responsibility for, but not limited to, the identification of product needs and opportunities, the development of alternatives as required, and the selection of a preferred plan. Product Planning also secures management approval of recommended products, monitors implementation, and provides surveillance and controls within established precepts as the program progresses.

 

PRODUCT/ENGINEERING LETTERS

These are official communications by which product direction is transmitted to the various corporate organizations. This direction delineates additions, deletions and revisions to the rpoduct offering.                       Approval of these letters prior to issuance is generally a reciprocal action, with "Vechicle Engineering" reviewing and concurring in capability with regard to Product Letter actions and Product Planning providing agreemtn that any effect on "Product Content" as propsed in Engineering Letters is within the precepts of the program plan. Sepcial Committees are normally established for the review and approval of these letters.                Issuance conveys to the recipient that all financial, timing and manpower considerations have been approved to cover the action directed in this regard, therefore, limitations of action must be clearly defined and the following is a listing of "work classifications" which may be elected for Product/Engineering.                                  LETTERS:  1. "Action Release" - complete all phases of engineering work up to and including release for production.  2. "Investigation through Feasibility" - complete all design development and testing required to establish cost, design, and manufacturing feasibility. Prototype tooling is authoorized as required but no realse action is to be initiated.  3. ""Inveestigation - Paper Study" - complete drawings (new or marked-up), sketches or text descriptions, compile add and delete lists together with any additional data required to estimate/evaluate engineering, production tooling and piece costs.  4. "Other" - actions not covered by 1., 2., or 3. above e.g., installations for management appraisal where prototype tooling is not authorized, program concellations, etc.   When using this work classification, specific detail of the engineering work to be performed is to be included in the test letter.

 

PRODUCTION SAMPLES

Vehicle component parts, produced from production tools, which are shipped in limited quantities upon request, in support of prove-out and sign-off requirements mandatory to the authorization of "volume" shipments for production. (Normally 6 months prior to Job #1.)

 

PROFESSIONAL RECONSTRUCTION

The effort to determine, from available information, how the accident happened.  Reconstruction is the fourth level of traffic accident investigation.  It involves studying results of the accident, considering other circumstances, and applying scientific principles to form opinions relative to events of the accident which are otherwise unknown or are a matter of dispute.

 

PROGRAM CONTENT

A translation of the Product Objectives into basic Engineering terminology (normally by Vehicle Engineering and Product Planning), which includes the Vehicle Weight, Cost, Timing,  Serviceability and Package Objectives, Body Types (including a definition of all derivative models to be considered in design) Wheelbases, Tread, Overall Length and Height Engine/Transmission and Brake Combinations and Regular Production Options (RPOs).

 

PROGRAM TIMING

The activity having prime responsibility for, but not limited to:  1. Establishment and control of program timing plans.  2. Coordination of product changes.  3. Analysis of all vehicle product changes for obsolescence prevention control.  4. Establishment and control of the vehicle "Pink Report".  5. Coordination and reporting part complexity counts.

 

PROGRESSIVE SHIFTING

A process of shifting high torque rise engines that involves shifting at lower rpm’s at slower speeds, and at progressively higher rpm’s as the speed of the vehicle increases. 

 

PROHIBITED ARTICLES

Articles of freight which will not be handled.

 

PRONY BRAKE

Mechanical device used to determine the brake horsepower of an internal combustion engine.

 

PROPELLER SHAFT

Driveshaft used to transmit torque from engine or transmission to rear axle.

 

PROPORTIONING VALVE

A device (valve) in the braking system used to balance the braking force between the front and rear brakes

 

PROVEOUT MODEL

A clay model developed to verify surface drawing conformation with the appearance of the model originally approved by management. A record cast subsequently is made in Fiberglass. (See record model).

 

PS

(Process Standard) Specification of a production process to be followed in processing a part of achieve a satisfactory result. (Chrysler derived)

 

psi

Pounds per square inch - English unit of pressure.

 

PSP

(Problem Solving Process) The GM Quality Network's Problem Solving Process Action Strategy. The process contains four tasks: Select, Contain, Correct, and Prevent. Described in GP-5.

 

PUBLIC SERVICE COMMISSION

A name usually given to a State body having control of, or regulating public utilities.

 

PUDDLE

A wet area on the road or roadside where dribble accumulates after a vehicle has come to rest.  A puddle often marks the final position of a vehicle after an accident.

 

PULL THE PIN

Release the fifth wheel lock.

Pulse Width
The number of engine revolution degrees that an injector is open to deliver fuel. ( Detroit )

Pump On Distance
The distance traveled by a fire rescue truck which pumps water and moves at the same time. ( Detroit )

Pump On Fuel
The fuel used while operating in the pressure governor mode. ( Detroit )

Pump On Time
The time the engine is running in the pressure governor mode. This mode is active when the engine is used to drive a water pump in a fire truck application. ( Detroit )

PUP

(Slang) A short four-wheel trailer which is pulled behind a semi-trailer or a straight truck.

 

PURE PYRO INFLATOR

An ACRS inflator which contains a pyrotechnic gas generator but not stored gas.

 

PUSH GUN

single Tip Weld Gun

 

PUSHER

An extra engine at the rear of a train used to assist a train in climbing a grade.

 

PUSHER AXLE

A non-driven (dead) axle installed forward of the driven axle(s) to increase the permissible gross weight, and consequently the payload.

 

PUT ON THE AIR

(Slang)  Apply the brakes.

 

PUT ON THE IRON

(Slang)  Put on the tire chains.

 

PVS

Product Verification Specification

 

PYROMETER

An instrument that registers the temperature of the exhaust gases.

 

PYROTECHNIC

An explosive substance to operate, ignite or heat by means of rapid combustion.

 

References

Detroit Diesel

Caterpillar User's Manual