Aeronautical Terms beginning with P
Pilot Briefing Information
The current format for charted IAPs issued by NACO. The information is presented in a logical order facilitating pilot briefing of the procedures. Charts include formatted information required for quick pilot or flight crew reference located at the top of the chart.
Point-in-Space (PinS)Approach
An approach normally developed to heliports that do not meet the IFR heliport design standards but meet the standards for a VFR heliport. A helicopter PinS approach can be developed using conventional NAVAIDs or RNAV systems. These procedures have either a VFR or visual segment between the MAP and the landing area. The procedure will specify a course and distance from the MAP to the heliport(s) and include a note to proceed VFR or visually from the MAP to the heliport, or conduct the missed approach.
Positive Course Guidance (PCG)
A continuous display of navigational data that enables an aircraft to be flown along a specific course line, e.g., radar vector, RNAV, ground-based NAVAID.
Precision Runway Monitor (PRM)
Provides air traffic controllers with high precision secondary surveillance data for aircraft on final approach to parallel runways that have extended centerlines separated by less than 4,300 feet. High resolution color monitoring displays (FMA) are required to present surveillance track data to controllers along with detailed maps depicting approaches and a no transgression zone.
Preferential Departure Route (PDR)
A specific departure route from an airport or terminal area to an en route point where there is no further need for flow control. It may be included in an instrument Departure Procedure (DP) or a Preferred IFR Route.
Preferred IFR Routes
A system of preferred IFR routes guides you in planning your route of flight to minimize route changes during the operational phase of flight, and to aid in the efficient orderly management of air traffic using federal airways.
Principal Operations Inspector (POI)
Scheduled air carriers and operators for compensation or hire are assigned a principal operations inspector (POI) who works directly with the company and coordinates FAA operating approval.
P-Factor
A tendency for an aircraft to yaw to the left due to the for descending propeller blade on the right producing more thrust than the ascending blade on the left. This occurs when the aircraft’s longitudinal axis is in a climbing attitude in relation to the relative wind. The P-factor would be to the right if the aircraft had a counterclockwise rotating propeller.
Parasite Drag
That part of total drag created by the design or shape of airplane parts. Parasite drag increases with an increase in airspeed.
Payload (GAMA)
The weight of occupants, cargo, and baggage.
Pilot’s Operating Handbook (POH)
A document developed by the airplane manufacturer and contains the FAA approved Airplane Flight Manual (AFM) information.
Piston Engine
A reciprocating engine.
Pitch
The rotation of an airplane about its lateral axis, or on a propeller, the blade angle as measured from plane of rotation.
Pivotal Altitude
A specific altitude at which, when an airplane turns at a given groundspeed, a projecting of the sighting reference line to a selected point on the ground will appear to pivot on that point.
Pneumatic Systems
The power system in an aircraft used for operating such items as landing gear, brakes, and wing flaps with compressed air as the operating fluid.
Porpoising
Oscillating around the lateral axis of the aircraft during landing.
Position Lights
Lights on an aircraft consisting of a red light on the left wing, a green light on the right wing, and a white light on the tail. CFRs require that these lights be displayed in flight from sunset to sunrise.
Positive Static Stability
The initial tendency to return to a state of equilibrium when disturbed from that state.
Power
Implies work rate or units of work per unit of time, and as such, it is a function of the speed at which the force is developed. The term “power required” is generally associated with reciprocating engines.
Power Distribution Bus
A Bus Bar. An electrical power distribution point to which several circuits may be connected. It is often a solid metal strip having a number of terminals installed on it.
Power Lever
The cockpit lever connected to the fuel control unit scheduling fuel flow to the combustion chambers of a turbine engine.
Powerplant
A complete engine and propeller combination with accessories.
Practical Slip Limit
The maximum slip an aircraft is capable of performing due to rudder travel limits.
Precession
The tilting or turning of a gyro in response to deflective forces causing slow drifting and erroneous indications in gyroscopic instruments.
Preignition
Ignition occurring in the cylinder before the time of normal ignition. Preignition is often caused by a local hot spot in the combustion chamber igniting the fuel/air mixture.
Pressure Altitude
The altitude indicated when the altimeter setting window (barometric scale) is adjusted to 29.92. This is the altitude above the standard datum plane, which is a theoretical plane where air pressure (corrected to 15ºC) equals 29.92 in. Hg. Pressure altitude is used to compute density altitude, true altitude, true airspeed, and other performance data.
Profile Drag
The total of the skin friction drag and form drag for a two-dimensional airfoil section.
Propeller
A device for propelling an aircraft that, when rotated, produces by its action on the air, a thrust approximately perpendicular to its plane of rotation. It includes the control components normally supplied by its manufacturer.
Propeller Blade Angle
The angle between the propeller chord and the propeller plane of rotation.
Propeller Lever
The control on a free power turbine turboprop that controls propeller speed and the selection for propeller feathering.
Propeller Slipstream
The volume of air accelerated behind a propeller producing thrust.
Propeller Synchronization
A condition in which all of the propellers have their pitch automatically adjusted to maintain a constant r.p.m. among all of the engines of a multiengine aircraft.
P-static
Precipitation Static.
Parasite drag
Drag caused by the friction of air moving over the aircraft structure; its amount varies directly with the airspeed.
Pilot-in-command (PIC)
The pilot responsible for the operation and safety of an aircraft.
Pilot report (PIREP)
Report of meteorological phenomena encountered by aircraft.
Pilot’s Operating Handbook/Airplane Flight Manual (POH/AFM)
FAA-approved documents published by the airframe manufacturer that list the operating conditions for a particular model of aircraft.
Pitot pressure
Ram air pressure used to measure airspeed.
Pitot-static head
A combination pickup used to sample pitot pressure and static air pressure.
Plan view
The overhead view of an approach procedure on an instrument approach chart. The plan view depicts the routes that guide the pilot from the en route segments to the IAF.
Point-in-space approach
A type of helicopter instrument approach procedure to a missed approach point more than 2,600 feet from an associated helicopter landing area.
Position error
Error in the indication of the altimeter, ASI, and VSI caused by the air at the static system entrance not being absolutely still.
Position report
A report over a known location as transmitted by an aircraft to ATC.
Precession
The characteristic of a gyroscope that causes an applied force to be felt, not at the point of application, but 90° from that point in the direction of rotation.
Precipitation static (P-static)
A form of radio interference caused by rain, snow, or dust particles hitting the antenna and inducing a small radio-frequency voltage into it.
Precision approach
A standard instrument approach procedure in which both vertical and horizontal guidance is provided.
Precision approach path indicator (PAPI)
A system of lights similar to the VASI, but consisting of one row of lights in two- or four-light systems. A pilot on the correct glide slope will see two white lights and two red lights. See VASI.
Precision approach radar (PAR)
A type of radar used at an airport to guide an aircraft through the final stages of landing, providing horizontal and vertical guidance. The radar operator directs the pilot to change heading or adjust the descent rate to keep the aircraft on a path that allows it to touch down at the correct spot on the runway.
Precision runway monitor (PRM)
System allows simultaneous, independent Instrument Flight Rules (IFR) approaches at airports with closely spaced parallel runways.
Preferred IFR routes
Routes established in the major terminal and en route environments to increase system efficiency and capacity. IFR clearances are issued based on these routes, listed in the A/FD except when severe weather avoidance procedures or other factors dictate otherwise.
Pressure altitude
Altitude above the standard 29.92" Hg plane.
Prevailing visibility
The greatest horizontal visibility equaled or exceeded throughout at least half the horizon circle (which is not necessarily continuous).
Primary and supporting
A method of attitude instrument flying using the instrument that provides the most direct indication of attitude and performance.
Primary flight display (PFD)
A display that provides increased situational awareness to the pilot by replacing the traditional six instruments used for instrument flight with an easy-to-scan display that provides the horizon, airspeed, altitude, vertical speed, trend, trim, rate of turn among other key relevant indications.
Procedure turn
A maneuver prescribed when it is necessary to reverse direction to establish an aircraft on the intermediate approach segment or final approach course.
Profile view
Side view of an IAP chart illustrating the vertical approach path altitudes, headings, distances, and fixes.
Prohibited area
Designated airspace within which flight of aircraft is prohibited.
Propeller/rotor modulation error
Certain propeller RPM settings or helicopter rotor speeds can cause the VOR course deviation indicator (CDI) to fluctuate as much as ±6°. Slight changes to the RPM setting will normally smooth out this roughness.
Perceptions
The basis of all learning, perceptions result when a person gives meaning to external stimuli or sensations. Meaning derived from perception is influenced by an individual’s experience and many other factors.
Performance-based objectives
A statement of purpose for a lesson or instructional period that includes three elements: a description of the skill or behavior desired of the student, a set of conditions under which the measurement will be taken, and a set of criteria describing the standard used to measure accomplishment of the objective.
Personal computer-based aviation training device (PCATD)
A device which uses software which can be displayed on a personal computer to replicate the instrument panel of an airplane. A PCATD must replicate a type of airplane or family of airplanes and meet the virtual control requirements specified in AC 61-126.
Personality
The embodiment of personal traits and characteristics of an individual that are set at a very early age and are extremely resistant to change.
Physical organism
A perception factor that describes a person’s ability to sense the world around them.
Pilot error
Pilot action/inaction or decision/indecision causing or contributing to an accident or incident.
Poor judgment chain
A series of mistakes that may lead to an accident or incident. Two basic principles generally associated with the creation of a poor judgment chain are: (1) one bad decision often leads to another; and (2) as a string of bad decisions grows, it reduces the number of subsequent alternatives for continued safe flight. Aeronautical decision- making is intended to break the poor judgment chain before it can cause an accident or incident.
Practical Test Standards (PTS)
An FAA published list of standards which must be met for the issuance of a particular pilot certificate or rating. FAA inspectors and designated pilot examiners use these standards when conducting pilot practical tests and flight instructors should use the PTS while preparing applicants for practical tests. (Obsolete term, replaced by Airman Certification Standards)
Preparation
The first step of the teaching process, which consists of determining the scope of the lesson, the objectives, and the goals to be attained. This portion also includes making certain all necessary supplies are on hand. When using the telling-and-doing technique of flight instruction, this step is accomplished prior to the flight lesson.
Presentation
The second step of the teaching process, which consists of delivering information or demonstrating the skills that make up the lesson. The delivery could be by either the lecture method or demonstration-performance method. In the telling-and-doing technique of flight instruction, this is the segment in which the instructor both talks about and performs the procedure.
Pretest
A test used to determine whether a student has the necessary qualifications to begin a course of study. Also used to determine the level of knowledge a student has in relation to the material that will be presented in the course.
Primacy
A principle of learning in which the first experience of something often creates a strong, almost unshakable impression. The importance to an instructor is that the first time something is demonstrated, it must be shown correctly since that experience is the one most likely to be remembered by the student.
Problem-based learning
Lessons in such a way as to confront students with problems that are encountered in real life which force them to reach real-world solutions.
Psychomotor domain
A grouping of levels of learning associated with physical skill levels which range from perception through set, guided response, mechanism, complex overt response, and adaptation to origination.
Parachute
A device used or intended to be used to retard the fall of a body or object through the air.
Person
An individual, firm, partnership, corporation, company, association, joint-stock association, or governmental entity. It includes a trustee, receiver, assignee, or similar representative of any of them.
Pilotage
Navigation by visual reference to landmarks.
Pilot in command
The person who:
(1) Has final authority and responsibility for the operation and safety of the flight;
(2) Has been designated as pilot in command before or during the flight; and
(3) Holds the appropriate category, class, and type rating, if appropriate, for the conduct of the flight.
Pitch setting
The propeller blade setting as determined by the blade angle measured in a manner, and at a radius, specified by the instruction manual for the propeller.
Positive control
Control of all air traffic, within designated airspace, by air traffic control.
Powered parachute
A powered aircraft comprised of a flexible or semi-rigid wing connected to a fuselage so that the wing is not in position for flight until the aircraft is in motion. The fuselage of a powered parachute contains the aircraft engine, a seat for each occupant and is attached to the aircraft’s landing gear.
Powered-lift
A heavier-than-air aircraft capable of vertical takeoff, vertical landing, and low speed flight that depends principally on engine-driven lift devices or engine thrust for lift during these flight regimes and on nonrotating airfoil(s) for lift during horizontal flight.
Precision approach procedure
A standard instrument approach procedure in which an electronic glide slope is provided, such as ILS and PAR.
Preventive maintenance
Simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations.
Prohibited area
A prohibited area is airspace designated under part 73 within which no person may operate an aircraft without the permission of the using agency.
Propeller
A device for propelling an aircraft that has blades on an engine-driven shaft and that, when rotated, produces by its action on the air, a thrust approximately perpendicular to its plane of rotation. It includes control components normally supplied by its manufacturer, but does not include main and auxiliary rotors or rotating airfoils of engines.
Public aircraft
Any of the following aircraft when not being used for a commercial purpose or to carry an individual other than a crewmember or qualified non-crewmember:
(1) An aircraft used only for the United States Government; an aircraft owned by the Government and operated by any person for purposes related to crew training, equipment development, or demonstration; an aircraft owned and operated by the government of a State, the District of Columbia, or a territory or possession of the United States or a political subdivision of one of these governments; or an aircraft exclusively leased for at least 90 continuous days by the government of a State, the District of Columbia, or a territory or possession of the United States or a political subdivision of one of these governments.
(i) For the sole purpose of determining public aircraft status, commercial purposes means the transportation of persons or property for compensation or hire, but does not include the operation of an aircraft by the armed forces for reimbursement when that reimbursement is required by any Federal statute, regulation, or directive, in effect on November 1, 1999, or by one government on behalf of another government under a cost reimbursement agreement if the government on whose behalf the operation is conducted certifies to the Administrator of the Federal Aviation Administration that the operation is necessary to respond to a significant and imminent threat to life or property (including natural resources) and that no service by a private operator is reasonably available to meet the threat.
(ii) For the sole purpose of determining public aircraft status, governmental function means an activity undertaken by a government, such as national defense, intelligence missions, firefighting, search and rescue, law enforcement (including transport of prisoners, detainees, and illegal aliens), aeronautical research, or biological or geological resource management.
(iii) For the sole purpose of determining public aircraft status, qualified non-crewmember means an individual, other than a member of the crew, aboard an aircraft operated by the armed forces or an intelligence agency of the United States Government, or whose presence is required to perform, or is associated with the performance of, a governmental function.
(2) An aircraft owned or operated by the armed forces or chartered to provide transportation to the armed forces if—
(i) The aircraft is operated in accordance with title 10 of the United States Code;
(ii) The aircraft is operated in the performance of a governmental function under title 14, 31, 32, or 50 of the United States Code and the aircraft is not used for commercial purposes; or
(iii) The aircraft is chartered to provide transportation to the armed forces and the Secretary of Defense (or the Secretary of the department in which the Coast Guard is operating) designates the operation of the aircraft as being required in the national interest.
(3) An aircraft owned or operated by the National Guard of a State, the District of Columbia, or any territory or possession of the United States, and that meets the criteria of paragraph (2) of this definition, qualifies as a public aircraft only to the extent that it is operated under the direct control of the Department of Defense.
Permanent Ballast (fixed ballast)
A weight permanently installed in an aircraft to bring its center of gravity into allowable limits. Permanent ballast is part of the aircraft empty weight.
Payload
(GAMA) Weight of occupants, cargo, and baggage.
Pilot’s Operating Handbook (POH)
An FAA-approved document published by the airframe manufacturer that lists the operating conditions for a particular model of aircraft and its engine(s).
Potable Water
Water carried in an aircraft for the purpose of drinking.
Pressure altitude
The altitude in the standard atmosphere at which the pressure is the same as at the point in question. Since an altimeter operates solely on pressure, this is the uncorrected altitude indicated by an altimeter set at standard sea level pressure of 29.92 inches or 1013 millibars.
Precipitation attenuation
Reduction of power density because of absorption or reflection of energy by precipitation.
Parcel
A small volume of air, small enough to contain uniform distribution of its meteorological properties, and large enough to remain relatively self-contained and respond to all meteorological processes. No specific dimensions have been defined, however, the order of magnitude of 1 cubic foot has been suggested.
Partial obscuration
A designation of sky cover when part of the sky is hidden by surface based obscuring phenomena.
Pilot balloon
A small free-lift balloon used to determine the speed and direction of winds in the upper air.
Pilot balloon observation (commonly called PIBAL)
A method of winds-aloft observation by visually tracking a pilot balloon.
Plan position indicator (PPI) scope
A radar indicator scope displaying range and azimuth of targets in polar coordinates.
Plow wind
The spreading downdraft of a thunderstorm; a strong, straight-line wind in advance of the storm. Also called first gust.
Polar air
An air mass with characteristics developed over high latitudes, especially within the subpolar highs. Continental polar air (cP) has cold surface temperatures, low moisture content, and, especially in its source regions, has great stability in the lower layers. It is shallow in comparison with Arctic air. Maritime polar (mP) initially possesses similar properties to those of continental polar air, but in passing over warmer water it becomes unstable with a higher moisture content. Compare tropical air.
Polar front
The semipermanent, semicontinuous front separating air masses of tropical and polar origins.
Power density
In radar meteorology the amount of radiated energy per unit cross sectional area in the radar beam.
Precipitation
Any or all forms of water particles, whether liquid or solid, that fall from the atmosphere and reach the surface. It is a major class of hydrometeor, distinguished from cloud and virga in that it must reach the surface.
Pressure altimeter
An aneroid barometer with a scale graduated in altitude instead of pressure using standard atmospheric pressure-height relationships; shows indicated altitude (not necessarily true altitude); may be set to measure altitude (indicated) from any arbitrarily chosen level.
Pressure gradient
The rate of decrease of pressure per unit distance at a fixed time.
Pressure jump
A sudden, significant increase in station pressure.
Pressure tendency
Barometric tendency. The change of barometric pressure within a specified period of time. In aviation weather observation, routinely determined periodically, usually for a 3-hour period.
Prevailing easterlies
The broad current or pattern of persistent easterly winds in the Tropics and in polar regions.
Prevailing visibility
In the U.S., the greatest horizontal visibility which is equaled or exceeded throughout half of the horizon circle; it need not be a continuous half.
Prevailing westerlies
The dominant west-to-east motion of the atmosphere, centered over middle latitudes of both hemispheres.
Prevailing wind
Direction from which the wind blows most frequently.
Prognostic chart (contracted PROG)
A chart of expected or forecast conditions.
Pseudo-adiabatic lapse rate
Saturated-adiabatic lapse rate. The rate of decrease of temperature with height as saturated air is lifted with no gain or loss of heat from outside sources; varies with temperature, being greatest at low temperatures.
Psychrometer
An instrument consisting of a wet-bulb and a dry-bulb thermometer for measuring wet-bulb and dry-bulb temperature; used to determine water vapor content of the air.
Pulse
Pertaining to radar, a brief burst of electromagnetic radiation emitted by the radar; of very short time duration.
Pulse length
Pertaining to radar, the dimension of a radar pulse; may be expressed as the time duration or the length in linear units. Linear dimension is equal to time duration multiplied by the speed of propagation (approximately the speed of light).
Positive vorticity
Vorticity caused by cyclonic turning; it is associated with upward motion of the air.
Parallels
Lines of latitude.
Parasite drag
Drag caused by the friction of air moving over the aircraft structure; its amount varies directly with the airspeed.
Payload (GAMA)
The weight of occupants, cargo, and baggage.
Personality
The embodiment of personal traits and characteristics of an individual that are set at a very early age and extremely resistant to change.
P-factor
A tendency for an aircraft to yaw to the left due to the descending propeller blade on the right producing more thrust than the ascending blade on the left. This occurs when the aircraft’s longitudinal axis is in a climbing attitude in relation to the relative wind. The P-factor would be to the right if the aircraft had a counterclockwise rotating propeller.
Phugoid oscillations
Long-period oscillations of an aircraft around its lateral axis. It is a slow change in pitch accompanied by equally slow changes in airspeed. Angle of attack remains constant, and the pilot often corrects for phugoid oscillations without even being aware of them.
Pilotage
Navigation by visual reference to landmarks.
Pilot in command (PIC)
The pilot responsible for the operation and safety of an aircraft.
Pilot report (PIREP)
Report of meteorological phenomena encountered by aircraft.
Pilot’s Operating Handbook/Airplane Flight Manual (POH/AFM)
FAA-approved documents published by the airframe manufacturer that list the operating conditions for a particular model of aircraft.
Pitot pressure
Ram air pressure used to measure airspeed.
Pitot-static head
A combination pickup used to sample pitot pressure and static air pressure.
Plan view
The overhead view of an approach procedure on an instrument approach chart. The plan view depicts the routes that guide the pilot from the en route segments to the IAF.
Planform
The shape or form of a wing as viewed from above. It may be long and tapered, short and rectangular, or various other shapes.
Pneumatic
Operation by the use of compressed air.
Point-in-space approach
A type of helicopter instrument approach procedure to a missed approach point more than 2,600 feet from an associated helicopter landing area.
Poor judgment chain
A series of mistakes that may lead to an accident or incident. Two basic principles generally associated with the creation of a poor judgment chain are: (1) one bad decision often leads to another; and (2) as a string of bad decisions grows, it reduces the number of subsequent alternatives for continued safe flight. ADM is intended to break the poor judgment chain before it can cause an accident or incident.
Position error
Error in the indication of the altimeter, ASI, and VSI caused by the air at the static system entrance not being absolutely still.
Position report
A report over a known location as transmitted by an aircraft to ATC.
Positive static stability
The initial tendency to return to a state of equilibrium when disturbed from that state.
Power
Implies work rate or units of work per unit of time, and as such, it is a function of the speed at which the force is developed. The term “power required” is generally associated with reciprocating engines.
Powerplant
A complete engine and propeller combination with accessories.
Precession
The characteristic of a gyroscope that causes an applied force to be felt, not at the point of application, but 90° from that point in the direction of rotation.
Precipitation
Any or all forms of water particles (rain, sleet, hail, or snow) that fall from the atmosphere and reach the surface.
Precipitation static (P-static)
A form of radio interference caused by rain, snow, or dust particles hitting the antenna and inducing a small radio-frequency voltage into it.
Precision approach
A standard instrument approach procedure in which both vertical and horizontal guidance is provided.
Precision approach path indicator (PAPI)
A system of lights similar to the VASI, but consisting of one row of lights in two- or four-light systems. A pilot on the correct glideslope will see two white lights and two red lights. See VASI.
Precision approach radar (PAR)
A type of radar used at an airport to guide an aircraft through the final stages of landing, providing horizontal and vertical guidance. The radar operator directs the pilot to change heading or adjust the descent rate to keep the aircraft on a path that allows it to touch down at the correct spot on the runway.
Precision runway monitor (PRM)
System allows simultaneous, independent instrument flight rules (IFR) approaches at airports with closely spaced parallel runways.
Preferred IFR routes
Routes established in the major terminal and en route environments to increase system efficiency and capacity. IFR clearances are issued based on these routes, listed in the A/FD except when severe weather avoidance procedures or other factors dictate otherwise.
Preignition
Ignition occurring in the cylinder before the time of normal ignition. Preignition is often caused by a local hot spot in the combustion chamber igniting the fuel-air mixture.
Pressure altitude
Altitude above the standard 29.92 "Hg plane.
Pressure demand oxygen system
A demand oxygen system that supplies 100 percent oxygen at sufficient pressure above the altitude where normal breathing is adequate. Also referred to as a pressure breathing system.
Prevailing visibility
The greatest horizontal visibility equaled or exceeded throughout at least half the horizon circle (which is not necessarily continuous).
Preventive maintenance
Simple or minor preservative operations and the replacement of small standard parts not involving complex assembly operation as listed in 14 CFR part 43, appendix A. Certificated pilots may perform preventive maintenance on any aircraft that is owned or operated by them provided that the aircraft is not used in air carrier service.
Primary and supporting
A method of attitude instrument flying using the instrument that provides the most direct indication of attitude and performance.
Primary flight display (PFD)
A display that provides increased situational awareness to the pilot by replacing the traditional six instruments used for instrument flight with an easy-to-scan display that provides the horizon, airspeed, altitude, vertical speed, trend, trim, and rate of turn among other key relevant indications.
Procedure turn
A maneuver prescribed when it is necessary to reverse direction to establish an aircraft on the intermediate approach segment or final approach course.
Profile view
Side view of an IAP chart illustrating the vertical approach path altitudes, headings, distances, and fixes.
Prohibited area
Designated airspace within which flight of aircraft is prohibited.
Propeller
A device for propelling an aircraft that, when rotated, produces by its action on the air, a thrust approximately perpendicular to its plane of rotation. It includes the control components normally supplied by its manufacturer.
Propeller/rotor modulation error
Certain propeller RPM settings or helicopter rotor speeds can cause the VOR course deviation indicator (CDI) to fluctuate as much as ±6°. Slight changes to the RPM setting will normally smooth out this roughness.
Buy from Amazon
