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Abatement:

The method of reducing the degree of intensity of noise and the use of such a method.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

https://www.massport.com/environment/environmental-reporting/noise-abatement/

Absolute Altitude:

The measurable height of an aircraft above the actual terrain.

AEROFILES http://www.aerofiles.com/glossary.html

Acoustics:

The science of sound, including its production, transmission, and effects.

http://asa.aip.org/pierce.html

AGL:

The distance Above Ground Level.

Aileron:

The movable areas of a wing form that control or affect the roll of an aircraft by working opposite one another -- up-aileron on the right wing and down-aileron on the left wing.

AEROFILES http://www.aerofiles.com/glossary.html

Amplitude:

The instantaneous magnitude of an oscillating quantity such as sound pressure. The peak amplitude is the maximum value.

ANCA:

Airport Noise and Capacity Act of 1990, prohibits U.S. airports from adopting overly restrictive or outright punitive anti-noise ordinances.

http://maps.macnoise.com/newmacnoise/index2.php?section=resources&page=glossary

ARTCC or "Center"

Air Routine Traffic Control Center-A facility established to provide air traffic control service to aircraft operating on IFR flight plans within controlled airspace and principally during the en route phase of flight. When equipment capabilities and controller workload permit, certain advisory/assistance services may be provided to VFR aircraft.

AEROFILES http://www.aerofiles.com/glossary.html

Air Speed Indicator:

An instrument or device that measures the air speed of an aircraft through an air mass.

AEROFILES http://www.aerofiles.com/glossary.html

ATC:

Air Traffic Control - A service operated by the appropriate authority to promote the safe, orderly, and expeditious flow of air traffic.

AEROFILES http://www.aerofiles.com/glossary.html

Air Traffic Controller-This person works in the control tower and talks to pilots by radio. An Air Traffic Controller tells the pilots when and where they can land their planes at the airport.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

ATCT:

Air Traffic Controller Tower-A terminal facility that uses air/ground communications, visual signaling, and other devices to provide ATC services to aircraft operating in the vicinity of an airport or on the movement area. Authorizes aircraft to land or takeoff at the airport controlled by the tower or to transit the Class D airspace area regardless of flight plan or weather conditions (IFR or VFR). A tower may also provide approach control services (radar or non-radar).

Altimeter:

An adjustable aneroid-barometric cockpit instrument used to measure an aircraft's altitude.

AEROFILES http://www.aerofiles.com/glossary.html

Amphibian, Amphibion

A seaplane or floatplane with retractable wheels for use on land, as well. The latter spelling was used in the '20s and '30s but has since fallen out of favor.

AEROFILES http://www.aerofiles.com/glossary.html

Angle of Attack:

The acute angle at which a moving airfoil meets the air stream.

AEROFILES http://www.aerofiles.com/glossary.html

ANSI:

The American body that publishes the standards used by the acoustics professionals, stands for the American National Standards Institute Glossary of Common Noise Terminology.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

ANSI 12.3:

ANSI S12.3-1985 (R 2006) American National Standard Statistical Methods for Determining and Verifying Stated Noise Emission Values of Machinery and Equipment.

ASNA:

Aviation Safety and Noise Abatement Act of 1979, principle law supporting federal efforts to identify and reduce noise and non-compatible land uses around civil airports in the U.S.

http://maps.macnoise.com/newmacnoise/index2.php?section=resources&page=glossary

ASTM:

The American body that publishes standards outlining how to carry out certain acoustic measurements so that the results can be compared between different users, stands for the American Society for Testing Materials Glossary of Common Noise Terminology.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Average Noise Level:

the average single number noise level over a given period of time with a stated exchange rate.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

A-Weighted Scale:

The A-weighted scale is a scale that adjusts frequency content to approximate how the ear hears. It is implemented using A-weighted decibels (dBA). The dBA is the most common unit used for measuring environmental sound levels. It adjusts, or weights, the frequency components of sound to conform with the normal response of the human ear at conversational levels. dBA is an international metric that is used for assessing environmental noise exposure of all noise sources.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

https://www.massport.com/environment/environmental-reporting/noise-abatement/

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Background Noise:

The overall sum of all the noise present at a specific location and time usually measured or referred to without the presence of the main noticeable offending noise.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Bernoulli Effect:

Since the pressure of a fluid is proportional to its velocity, airflow over the upper surface of an airfoil causes suction [lift] because the air stream has sped up in relation to positive pressure of the airflow on the lower surface.

AEROFILES http://www.aerofiles.com/glossary.html

Broadband Noise:

Noise covering the whole of the audio range of frequencies and usually measured with one of the standard frequency weighting filters.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

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Camber:

The convex or concave curvature of an airfoil.

AEROFILES http://www.aerofiles.com/glossary.html

Cargo:

Any type of goods that a plane is carrying, including suitcases, golf bags and boxes.

Philadelphia -Kid's Corner Common Aviation Terms

http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

Center:

An Air Route Traffic Control Center (ARTCC).

AEROFILES http://www.aerofiles.com/glossary.html

Certificated Airport:

An airport operating under FAR Part 139. The FAA issues airport operating certificates to all airports serving scheduled or unscheduled air carrier aircraft designed for more than 30 passenger seats. Certificated airports must meet minimum safety standards in accordance with FAR Part 139.

AEROFILES http://www.aerofiles.com/glossary.html

Chord:

The measurable distance between the leading and trailing edges of a wing form.

AEROFILES http://www.aerofiles.com/glossary.html

Class G Airspace (Uncontrolled Airspace):

Airspace not designated as Class A, B, C, D or E.

AEROFILES http://www.aerofiles.com/glossary.html

Cockpit:

Area located at the front of the plane where the Pilot and Co-Pilot sit. All of the instruments and controls needed to fly the plane and talk to the control tower are also located in this area.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

Community Noise Equivalent Level:

The 24 hour average noise level of all hourly Leq measurements with a 10 dB penalty added to the levels between 2200 and 0700 hours and a 5 dB penalty added to the levels between 1900 and 2200 hours to reflect people's extra sensitivity to noise during the night and the evening.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Contact Flight:

Navigation in which altitude and flight path can be maintained by visual reference to the ground and its landmarks. Similar to VFR.

AEROFILES http://www.aerofiles.com/glossary.html

Contour Flight:

Contact Flight in and around mountainous areas following visual reference to the terrain's contours.

AEROFILES http://www.aerofiles.com/glossary.html

Controlled Airspace:

An airspace of defined dimensions within which air traffic control service is provided to IFR flights and to VFR flights in accordance with the airspace classification. Controlled airspace is a generic term that covers Class A, B, C, D, and E airspace. Controlled airspace is also that airspace within which all aircraft operators are subject to certain pilot qualifications, operating rules, and equipment requirements in FAR Part 91. For IFR operations in any class of controlled airspace, a pilot must file an IFR flight plan and receive an appropriate ATC clearance. Each B, C, and D airspace area designated for an airport contains at least one primary airport around which the airspace is designated (for specific designations and descriptions of the airspace classes, refer to FAR Part 71.

AEROFILES http://www.aerofiles.com/glossary.html

Control Tower:

This is the building where Air Traffic Controllers work. From here, the Air Traffic Controller talks to pilots who are on the ground and those who are in the air.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

Co-Pilot:

Person who sits in the cockpit with the Pilot. The Co-Pilot is also known as the first officer and monitors the plane's controls and gauges while the Pilot flies the plane.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

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Day Night Level (DNL):

The 24 hour average noise level of all hourly Leq measurements with a 10 dB penalty added to the levels between 2200 and 0700 hours to reflect people's extra sensitivity to noise during the night.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

dBA:

The A-weighted Decibel (dBA) is the most common unit used for measuring environmental sound levels. It adjusts, or weights, the frequency components of sound to conform with the normal response of the human ear at conversational levels. dBA is an international metric that is used for assessing environmental noise exposure of all noise sources.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

https://www.massport.com/environment/environmental-reporting/noise-abatement/

dBC:

The C-weighted Decibel (dBC) is the method of measuring sound which takes into account the low frequency components of noise sources, such as aircraft operations, and reflects their contribution to the environment.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

https://www.massport.com/environment/environmental-reporting/noise-abatement/

Descent:

The process of decreasing altitude.

http://www.bradleyairport.com/community/noise-glossary.php

Decibel:

A dimensionless unit of acoustic measurement in sound level meters where 0dB is the threshold of normal hearing and 130 dB is the threshold of pain.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Dirigible:

A lighter-than-air craft capable of being propelled and steered for controlled flight.

AEROFILES http://www.aerofiles.com/glossary.html

Dorsal Fin:

A lateral fin/rudder extension on the top of a fuselage.

AEROFILES http://www.aerofiles.com/glossary.html

Drag:

The resisting force exerted on an aircraft in its line of flight opposite in direction to its motion. Compare Thrust.

AEROFILES http://www.aerofiles.com/glossary.html

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Echolocation:

A physiological process for locating distant or invisible objects (as prey) by sound waves reflected back to the emitter (as a bat) from the objects.

http://www.merriam-webster.com/dictionary/Echolocation

Elevator:

The movable part of a horizontal airfoil which controls the pitch of an aircraft; the fixed part being the Stabilizer.

AEROFILES http://www.aerofiles.com/glossary.html

En Route Air Traffic Control Services:

Air traffic control services provided aircraft on IFR flight plans, generally by centers, when these aircraft are operating between departure and destination terminal areas. When equipment, capabilities, and controller workload permit, certain advisory/assistance services may be provided to VFR aircraft.

AEROFILES http://www.aerofiles.com/glossary.html

EPNdB:

The Effective Perceived Noise Level (EPNdB) is another unit of measure for aircraft noise. It is based on how people judge the annoyance of sounds they hear with corrections for the duration of the event and for pure tones. The Federal Aviation Administration (FAA) uses EPNdB in the certification of large transport planes for Federal Noise Regulations (FAR Part 36).

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

https://www.massport.com/environment/environmental-reporting/noise-abatement/

ETA:

Estimated Time of Arrival.

AEROFILES http://www.aerofiles.com/glossary.html

ETD:

Estimated Time of Departure.

AEROFILES http://www.aerofiles.com/glossary.html

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FAA:

Federal Aviation Administration, the federal agency that is responsible for the safe and efficient movement of aircraft through the National Airspace System. The FAA has broad legislative authority to create and enforce Federal Aviation Regulations.

http://maps.macnoise.com/newmacnoise/index2.php?section=resources&page=glossary

Fixed-Base Operator (FBO):

Fixed-Base Operator, a commercial operator supplying fuel, maintenance, flight training, and other services at an airport.

AEROFILES http://www.aerofiles.com/glossary.html

Fast Response:

A 1/8 second averaging time in the detector of a sound level meter.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Federal Air Regulation (FAR):

Federal Aviation Regulations (FARs) are rules provided by the Federal Aviation Administration. The FARs are part of the Code of Federal Regulations (CFR). CFR Title 14 provides regulations for aeronautics and space. Detailed information can be found at CFR Title 14 Aeronautics and Space.

The topics for some of the FARs follows. FAR Part 91 -General Aviation (portions apply to all operators) FAR Part 103 -Ultralight Vehicles FAR Part 105 -Parachute Jumping FAR Part 108 -Airplane Operator Security FAR Part 119 -Certification: Air Carriers and Commercial Operators FAR Part 121 -Domestic, Flag, and Supplemental Air Carriers and Commercial Operators of Large Aircraft FAR Part 123 -Travel Clubs FAR Part 125 -US Civil Airplanes, seating 20 or more passengers or a maximum payload capacity 6,000# or more FAR Part 127 -Air Carriers using helicopters for scheduled interstate flights (within the 48 contiguous states) FAR Part 129 -Foreign Air Carrier and Foreign Operators of US registered aircraft engaged in common carriage FAR Part 133 -Rotorcraft External Load Operations FAR Part 135 -Air Taxi Operators and Commercial Operators. FAR Part 137 -Agricultural Aircraft Operations. FAR Part 141 -Flight School.

http://ecfr.gpoaccess.gov/cgi/t/text/text-idx?sid=5046beff5d002977d4d117f0877f26b1&c=ecfr&tpl=/ecfrbrowse/Title14/14tab_02.tpl

Federal Interagency Committee on Aviation Noise (FICAN):

A committee formed in 1993 to provide forums for discussion of public and private sector proposals on aviation noise and to identify and encourage needed research. All Federal agencies concerned with aviation noise are represented on the committee, including the Department of Defense (Air Force, Army, Navy), Department of Interior (NPS), Department of Transportation (FAA), Environmental Protection Agency, National Aeronautics and Space Administration, and Department of Housing and Urban Development.

http://overflights.faa.gov/apps/GetFile.CFM?File_ID=118

FIN:

The fixed part of a vertical airfoil that controls the yaw of an aircraft; the movable part being the Rudder. Sometime referred to as Vertical Stabilizer.

AEROFILES http://www.aerofiles.com/glossary.html

FLAP:

A movable, usually hinged airfoil set in the trailing edge of an aircraft wing, designed to increase lift or drag by changing the camber of the wing or used to slow an aircraft during landing by increasing lift. Also see Fowler Lap, Slotted Flap, and Split flap.

AEROFILES http://www.aerofiles.com/glossary.html

Flight Attendant:

This person helps you find your seat on the plane, reviews safety information prior to takeoff, and serves you snacks and beverages while the plane is in the air.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

Flight Plan:

Specified information relating to the intended flight of an aircraft that is filed orally or in writing with an FSS or an ATC facility.

AEROFILES http://www.aerofiles.com/glossary.html

Flight Services Station (FSS):

Air traffic facilities which provide pilot briefing, enroute communications and VFR search and rescue services, assist lost aircraft and aircraft in emergency situations, relay ATC clearances, originate Notices to Airmen, broadcast aviation weather and NAS information, receive and process IFR flight plans, and monitor NAVAIDs. In addition, at selected locations, FSSs provide Enroute Flight Advisory Service (Flight Watch), take weather observations, issue airport advisories, and advise Customs and Immigration of transborder flights.

AEROFILES http://www.aerofiles.com/glossary.html

Frequency:

The small fluctuations in a sound that cover the audible range of tones from about 20 Hz to about 20 kHz for the normal hearing of an adult Glossary of Common Noise Terminology.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Frequency Analysis:

Analyzing an overall broadband noise to identify the different contributions in different parts of the audio spectrum.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Fuselage:

An aircraft's main body structure housing the flight crew, passengers, and cargo and to which the wings, tail and, in most single-engine airplanes, engine are attached.

AEROFILES http://www.aerofiles.com/glossary.html

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G or g:

See Load Factor.

AEROFILES http://www.aerofiles.com/glossary.html

Gates:

This is where you wait for your plane. Gates usually have seats that you can sit in and televisions that show information about the Airport and current news. Gates are also the areas where you leave the airport building to board your plane. You can either walk through a jetway/loading bridge or walk outside to get to your plane.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

General Aviation:

That portion of civil aviation which encompasses all facets of aviation except air carriers holding a certificate of public convenience and necessity from the Civil Aeronautics Board and large aircraft commercial operators.

AEROFILES http://www.aerofiles.com/glossary.html

Glide Slope:

(1) The angle between horizontal and the glide path of an aircraft. (2) A tightly-focused radio beam transmitted from the approach end of a runway indicating the minimum approach angle that will clear all obstacles; one component of an instrument landing system (ILS).

AEROFILES http://www.aerofiles.com/glossary.html

Global Positioning System (GPS):

Global Positioning System; satellite-based navigation.

AEROFILES http://www.aerofiles.com/glossary.html

Green Light:

Approval for landing. A carryover expression from days when aircraft for the most part had no radios, and communication from a control tower was by means of a light-gun that beamed various green, red, and yellow signals to pilots in the air and on the ground.

AEROFILES http://www.aerofiles.com/glossary.html

Gross Weight:

The total weight of an aircraft when fully loaded; aka Takeoff Weight.

AEROFILES http://www.aerofiles.com/glossary.html

Ground Control:

Tower control, by radioed instructions from air traffic control, of aircraft ground movements at an airport.

AEROFILES http://www.aerofiles.com/glossary.html

Ground Speed:

The actual speed that an aircraft travels over the ground -- its "shadow speed"; it combines the craft's airspeed and the wind speed relative to the aircraft's direction of flight.

AEROFILES http://www.aerofiles.com/glossary.html

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Hanger:

An enclosed structure for housing aircraft. Originated with the floating homes of the original German Zeppelins in which they were "hung" from cables,which explains the erroneous, oft-seen spelling of "hanger."

AEROFILES http://www.aerofiles.com/glossary.html

Helicopter:

A wingless aircraft acquiring its lift from revolving blades driven by an engine about a near-vertical axis. A ROTORCRAFT acquiring its primary motion from engine-driven rotors that accelerate the air downward, providing a reactive lift force, or accelerate the air at an angle to the vertical, providing lift and thrust.

AEROFILES http://www.aerofiles.com/glossary.html

Hushkit:

An aircraft-engine quieting device added to aircraft engines originally certified as Stage 2 in order to meet more stringent Stage 3 standards.

http://www.oharenoiose.org/glossary.htm

Hypersonic:

Speed of flight at or greater than Mach 5.0.

AEROFILES http://www.aerofiles.com/glossary.html

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Instrument Flight Rules (IFR):

Instrument Flight Rules, governing the conduct of flight under instrument meteorological conditions.

AEROFILES http://www.aerofiles.com/glossary.html

Instrument Meteorological Conditions (IMC):

Meteorological conditions expressed in terms of visibility, distance from clouds, and ceiling less than minima specified for visual meteorological conditions (VMC).

AEROFILES http://www.aerofiles.com/glossary.html

Integrated Noise Model (INM):

A computer model developed, updated and maintained by the FAA to predict the noise impacts generated by aircraft operations.

http://www.oharenoiose.org/glossary.htm

Intelligibility:

Capable of being understood or comprehended.

http://www.merriam-webster.com/dictionary/Intelligibility

For detailed discussion see the section on speech intelligibility methods in:Classroom Acoustics

International Organization for Standardization (ISO):

The international body that publishes the standards used by the acoustics professionals, stands for the International Standards Organization, deals with how acoustic measurements are to be performed.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

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Knot:

One nautical mile per hour, about 1.15 statute miles (6,080') per hour.

AEROFILES http://www.aerofiles.com/glossary.htm

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Lavg:

The average noise level over a period of time that uses an exchange rate of 4, 5 or 6 in the calculation of the final value.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Leq:

The equivalent continuous noise level that contains the same amount of noise energy as the actual varying noise, the Leq is a special case of the Lavg with the Q=3 exchange rate.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Lateral:

Situated on, directed toward, or coming from the side.

http://www.merriam-webster.com/dictionary

Lift:

The force exerted on the top of a moving airfoil as a low-pressure area that causes a wing form to rise.

AEROFILES http://www.aerofiles.com/glossary.html

Lift Drag Ratio:

The lift of a wing divided by the drag, or the lift coefficient divided by the drag coefficient, as the primary measure of the efficiency of an aircraft; aka L/D Ratio.

AEROFILES http://www.aerofiles.com/glossary.html

Load Factor:

The proportion between lift and weight commonly seen as g (sometimes capitalized) -- a unit of force equal to the force of gravity times one.

AEROFILES http://www.aerofiles.com/glossary.html

Lmax:

'''Maximum Noise Level (Lmax)' measures noise at its highest level during one noise event.

LORAN:

Long Range Navigation system, which utilizes timing differences between multiple low-frequency transmissions to provide accurate latitude/longitude position information to within 50'.

AEROFILES http://www.aerofiles.com/glossary.html

Loudness:

The subjective judgment of intensity of a sound by humans. Loudness depends upon the sound pressure and frequency of the stimulus.

http://overflights.faa.gov/apps/GetFile.CFM?File_ID=118

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Mach or m:

A number representing the ratio of the speed of an object to the speed of sound in the surrounding air or medium in which it is moving.

AEROFILES http://www.aerofiles.com/glossary.html

Masking:

To make indistinct or imperceptible.

http://www.merriam-webster.com/dictionary/masking

Maximum Sound Level:

The highest reading with a specified frequency weighting and time response in a sound level meter.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Minimum Sound Level:

The lowest reading with a specified frequency weighting and time response in a sound level meter.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Monocoque:

Type of fuselage design with little or no internal bracing other than bulkheads, where the outer skin bears the main stresses; usually round or oval in cross-section. Additional classifications are (1) Semi-Monocoque, where the skin is reinforced by longerons or bulkheads, but with no diagonal web members, and (2) Reinforced Shell, in which the skin is supported by a complete framework or structural members.

AEROFILES http://www.aerofiles.com/glossary.html

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National Airspace System (NAS):

The common network of US airspace; air navigation facilities, equipment and services, airports or landing areas; aeronautical charts, information and services; rules, regulations and procedures, technical information, and human resources and material. Included are system components shared jointly with the military.

AEROFILES http://www.aerofiles.com/glossary.html

NCP:

Noise Compatibility Program, a list of actions the airport proprietor, airport users, local governments, and the FAA propose to undertake to minimize existing and future noise/land use non-compatibilities.

http://maps.macnoise.com/newmacnoise/index2.php?section=resources&page=glossary

NEM:

Noise Exposure Map, describes the airport layout and operation, aircraft-related noise exposure, land uses in the airport environs, and the resulting noise/land use compatibility situation.

http://maps.macnoise.com/newmacnoise/index2.php?section=resources&page=glossary

NMS:

The Noise Monitoring System (NMS) is a sophisticated, acoustical system which monitors noise impacts by time of day, season and on an annual basis. It also monitors noise levels generated by a variety of outside aircraft activities and obtains accurate data of aircraft flight tracks and fleet mix. Massport's NMS uses ENOMS (Environmental Noise and Operations System) to collect and process the same information in a similar manner. The NMS has 29 locations in the Logan area and 6 locations at Hanscom.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

https://www.massport.com/environment/environmental-reporting/noise-abatement/

NOMS:

Noise and Operations Monitoring System, collects aircraft flight track data and noise event information for the analysis of flight patterns and the resulting noise impacts.

http://maps.macnoise.com/newmacnoise/index2.php?section=resources&page=glossary

Noise:

Most often defined as the presence of unwanted sounds, can be damaging to hearing if it is too loud or can be just annoying if it interferes with the normal enjoyment of others.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Noise Contour Map:

A map representing average annual noise levels summarized by lines connecting points of equal noise exposure.

http://www.oharenoiose.org/glossary.htm

Noise Reduction Rating:

The single number figure that gives an approximate method for choosing personal hearing protectors for workers in noisy industries, compare with the figure on the protector to choose the best one for the specific noise source under investigation.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Non-Auditory:

Not experienced through hearing.

http://www.merriam-webster.com/auditory

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Octave Band Analysis:

Analyzing a noise into smaller ranges of frequency where the normal audio range is split up into 9 or 10 separate bands each of which is an octave wide.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Ordinance:

A law passed by a local town or city or state to indicate any limits that have been imposed on the production of offending noises in the community, may be written in simple overall 'A' weighted terms or may require octave band measurements to control tonal problems.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

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Passerines:

Relating to the largest order (Passeriformes) of birds which includes over half of all living birds and consists chiefly of altricial songbirds of perching habits.

http://www.merriam-webster.com/dictionary/passerines

Pattern:

The path of aircraft traffic around an airfield, at an established height and direction. At tower-controlled fields the pattern is supervised by radio (or, in non-radio or emergency conditions by red and green light beams) by air traffic controllers.

AEROFILES http://www.aerofiles.com/glossary.html

Peak Response:

An equivalent averaging time of less than 0.0001 seconds in the detector of a sound level meter.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Peak Sound Level:

The absolute highest sound pressure of the noise signal of either the positive or negative part of the sound wave.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Percentile Sound Level:

The noise level, in decibels, exceeded for N % of the total measurement time such that the 10% level for an hour is the noise level exceeded for 6 minutes in total.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Periods:

The regular storage of noise levels during a run over medium to long term intervals such as 1 minute to 1 hour duration.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Permissible Exposure Level:

The 8 hour allowable long term noise level for a working days exposure.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Physiology:

A branch of biology that deals with the functions and activities of life or of living matter (as organs, tissues, or cells) and of the physical and chemical phenomena involved.

http://www.merriam-webster.com/dictionary/Physiology

Pilot:

Person who sits in the cockpit with the Co-Pilot and flies the plane.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

Pink Noise:

Broadband noise across the whole audio spectrum that contains an equal amount of energy in all octave or third octave bands.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Pinnipeds:

Any of an order or suborder (Pinnipedia) of aquatic carnivorous mammals (as a seal or walrus) with all four limbs modified into flippers.

http://www.merriam-webster.com/dictionary/Pinnipeds

Pitch:

(1) Of the three axes in flight, this specifies the vertical action, the up-and-down movement. Compare ROLL and YAW. (2) The angle of a propeller or rotor blade in relation to its arc; also the distance advanced by a blade in one full rotation.

AEROFILES http://www.aerofiles.com/glossary.html

Positive Control:

The separation of all air traffic within designated airspace by air traffic control.

AEROFILES http://www.aerofiles.com/glossary.html

Preferential runway use:

Taking off or landing on specified runways during certain hours to avoid residential areas.

http://www.casellausa.com/store/page.cfm?pageID=79504A404E

https://www.massport.com/environment/environmental-reporting/noise-abatement/

Profiles:

The storage of regular noise levels during a measurement to show how the noise varied with time, usually taken at short intervals such as 1 sec up to 1 minute.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

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RAPCON:

Radar Approach Control Facility A terminal ATC facility that uses radar and non-radar capabilities to provide approach control services to aircraft arriving, departing, or transiting airspace controlled by the facility. This facility provides radar ATC services to aircraft operating in the vicinity of one or more civil/military airports in a terminal area. The facility may provide services of a ground-controlled approach (GCA). A radar approach control facility may be operated by FAA or a military service, or jointly. Specific facility nomenclatures are used for administrative purposes only and are related to the physical location of the facility and the operating service generally:

AEROFILES http://www.aerofiles.com/glossary.html

Roll:

Of the three axes in flight, this specifies the action around a central point. Compare PITCH and YAW.

AEROFILES http://www.aerofiles.com/glossary.html

Rotary Engine:

A powerplant that rotates on a stationary propeller shaft. An American invention by Adams-Farwell Co (1896), it was first used for buses and trucks in the US (1903), then copied by French engineers for early aircraft engines (1914).

AEROFILES http://www.aerofiles.com/glossary.html

Rotorcraft:

A heavier-than-air aircraft that depends principally for its support in flight on the lift generated by one or more rotors. Includes helicopters and gyroplanes.

AEROFILES http://www.aerofiles.com/glossary.html

Rudder:

The movable part of a vertical airfoil which controls the yaw of an aircraft; the fixed part being the FIN.

AEROFILES http://www.aerofiles.com/glossary.html

Run-Up:

A routine procedure for testing an aircraft engine at a high power setting. Engine run-ups are normally conducted by airline maintenance personnel checking an aircraft engine or other on board system following maintenance.

http://www.oharenoiose.org/glossary.htm

Runway:

A strip of level ground, usually concrete, that airplanes takeoff and land on.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

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Security Checkpoints:

These are used to protect the flight crew and passengers from possible dangers when flying in the plane. These checkpoints prevent people from carrying weapons and dangerous materials onto the plane.

Philadelphia -Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

Speech Interference Level (SIL):

The speech interference level provides a way to evaluate how much a noise will interfere with the reception of speech. It is the arithmetic average of the levels in the octave bands that are most important for the understanding of speech. The octave bands centered at 500, 1000 and 2000 Hz are typically used in the calculation.

Separation:

The spacing of aircraft to achieve safe and orderly movement in flight and while landing and taking off.

http://www.bradleyairport.com/community/noise-glossary.php

Shock Waves:

A compressional wave of high amplitude caused by a shock (as from an earthquake or explosion) to the medium through which the wave travels.

http://www.merriam-webster.com/dictionary/shock%20wave

Signal-To-Noise Ratio:

Signal-to-noise ratio is the dimensionless ratio of the signal power to the noise power contained in a signal.

http://www.scholarpedia.org/article/Signal-to-noise_ratio

Slats:

Movable vanes or auxiliary airfoils, usually set along the leading edge of a wing but able to be lifted away at certain angles of attack.

AEROFILES http://www.aerofiles.com/glossary.html

Slot:

A long, narrow, spanwise gap in a wing, usually near the leading edge, to improve airflow at high angles of attack for slower landing speeds.

AEROFILES http://www.aerofiles.com/glossary.html

Slow Response:

A 1 second averaging time in the detector of a sound level meter.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Sone:

The unit used to assess the loudness of a noise that depends on its spectral content and level.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Sound Exposure Level (SEL):

The equivalent continuous noise level of an event including all the actual noise then referenced to a notional duration of 1 second.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Sound Insulation:

Reducing the sound level inside a building through the installation of specific building construction materials, and component assemblies that provide increased noise reduction characteristics.

http://www.bradleyairport.com/community/noise-glossary.php

Sound level meter:

An instrument, which is used for the measurement of sound level, with standard frequency weighting and standard exponentially weighted time averaging.

http://maps.macnoise.com/newmacnoise/index2.php?section=resources&page=glossary

Sound Power Level:

The total amount of noise inherent in a particular noise source independent of the acoustic environment that it is in.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Sound Pressure Level:

The instantaneous changing sound level with a selected frequency weighting and time response.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Special Use Area:

Airspace of defined dimensions identified by an area on the surface of the earth wherein activities must be confined because of their nature and/or wherein limitations may be imposed upon aircraft operations that are not a part of those activities.

AEROFILES http://www.aerofiles.com/glossary.html

Airspace established outside of Class A airspace area to separate or segregate certain non-hazardous military activities from IFR traffic and to identify for VFR traffic where these activities are conducted.

AEROFILES http://www.aerofiles.com/glossary.html

Airspace designated under part 73 within which no person may operate an aircraft without the permission of the using agency.

AEROFILES http://www.aerofiles.com/glossary.html

Airspace designated under FAR Part 73, within which the flight of aircraft, while not wholly prohibited, is subject to restriction. Most restricted areas are designated joint use and IFR/VFR operations in the area may be authorized by the controlling ATC facility when it is not being utilized by the using agency. Restricted areas are depicted on enroute charts. Where joint use is authorized, the name of the ATC controlling facility is also shown.

AEROFILES http://www.aerofiles.com/glossary.html

Spoiler:

A long, movable, narrow plate along the upper surface of an airplane wing used to reduce lift and increase drag by breaking or spoiling the smoothness of the airflow.

AEROFILES http://www.aerofiles.com/glossary.html

Stabilizer:

The fixed part of a horizontal airfoil that controls the pitch of an aircraft; the movable part being the ELEVATOR.

AEROFILES http://www.aerofiles.com/glossary.html

Stage 2 Aircraft:

Aircraft that meet the noise levels prescribed by FAR Part 36 and are less stringent than those established for the quieter "Stage 3" designation. The Airport Noise and Capacity Act required the phase-out of all Stage 2 aircraft over 75,000 pounds by December 31, 1999.

http://www.ohare.com/cnrc/midway/AviationGlossaryofTerms.pdf

Stage 3 Aircraft:

Aircraft that meet the most stringent noise levels set in FAR Part 36.

City of Chicago, Department of Aviation 7

http://www.ohare.com/cnrc/midway/AviationGlossaryofTerms.pdf

Supersonic:

Speed of flight at or greater than Mach 1.0; literally, faster than the speed of sound.

AEROFILES http://www.aerofiles.com/glossary.html

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Taxiway:

A strip of land that pilots drive their planes on before takeoff and afterlanding. Pilots use taxiways to drive back and forth between the gate area and the runway.

Philadelphia - Kid's Corner Common Aviation Terms http://www.phl.org/passengerinfo/KidsCorner/Pages/kids_alphabet.aspx

Terrestrial:

Relating to land as distinct from air or water.

http://www.merriam-webster.com/dictionary/terrestrial

Third Octave Band Analysis:

Analyzing a noise into smaller ranges of frequency where the normal audio range is split up into 27 or 30 separate bands each of which is a third octave wide.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Thrust:

The driving force of a propeller in the line of its shaft or the forward force produced in reaction to the gases expelled rearward from a jet or rocket engine. Opposite of DRAG.

AEROFILES http://www.aerofiles.com/glossary.html

Time Average Sound Level:

The equivalent steady level over a given period of time that contains the same amount of noise energy as the actual changing noise level.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Time Weighted Average Level:

The total amount of workplace noise exposure expressed as an equivalent standard 8 hour working day.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Torque:

A twisting, gyroscopic force acting in opposition to an axis of rotation, such as with a turning propeller; aka Torsion.

AEROFILES http://www.aerofiles.com/glossary.html

Touch and Go:

Landing practice wherein an aircraft does not make a full stop after a landing, but proceeds immediately to another take-off.

AEROFILES http://www.aerofiles.com/glossary.html

Transmission Loss:

The difference between the noise levels across a partition between two or more rooms.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Transponder:

An airborne transmitter that responds to ground-based interrogation signals to provide air traffic controllers with more accurate and reliable position information than would be possible with "passive" radar; may also provide air traffic control with an aircraft's altitude.

AEROFILES http://www.aerofiles.com/glossary.html

Turbojet:

An aircraft having a jet engine in which the energy of the jet operates a turbine that in turn operates the air compressor.

AEROFILES http://www.aerofiles.com/glossary.html

Turboprop:

An aircraft having a jet engine in which the energy of the jet operates a turbine that drives the propeller.

AEROFILES http://www.aerofiles.com/glossary.html

Turbulent Boundary Layer (TBL):

A boundary layer may be laminar or turbulent. A laminar boundary layer is one where the flow takes place in layers, i.e., each layer slides past the adjacent layers. A turbulent boundary layer contains mixing across several layers.

http://www-mdp.eng.cam.ac.uk/library/enginfo/aerothermal_dvd_only/aero/fprops/introvisc/node8.html

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Uncontrolled Airspace:

Class G Airspace; airspace not designated as Class A, B, C, D or E.

AEROFILES http://www.aerofiles.com/glossary.html

Undercarriage:

The landing gear of a land-based aircraft, including struts, frames, and wheels.

AEROFILES http://www.aerofiles.com/glossary.html

Ungulates:

A hoofed typically herbivorous quadruped mammal.

http://www.merriam-webster.com/dictionary/ungulates

USFWS:

United States Fish and Wildlife Service http://www.fws.gov

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Velocity:

Velocity is the rate of change of position and requires both speed and direction to define it. The speed is the distance travelled per unit of time. Velocity is defined for specific situations and maneuvers as follows:

AEROFILES http://www.aerofiles.com/glossary.html

Ventral Fin:

A fin/rudder extension on the bottom of a fuselage. Opposite of DORSAL FIN.

AEROFILES http://www.aerofiles.com/glossary.html

VFR:

Visual Flight Rules that govern the procedures for conducting flight under visual conditions. The term is also used in the US to indicate weather conditions that are equal to or greater than minimum VFR requirements. Also used by pilots and controllers to indicate a type of flight plan.

AEROFILES http://www.aerofiles.com/glossary.html

Vibration:

Movements of a body such as a machine or fan that are transmitted through the structure and detected as a motion with a given amplitude and frequency.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

Visual Meteorological Conditions (VMC):

Meteorological conditions expressed in terms of visibility, distance from clouds, and ceiling equal to or better than specified minima.

AEROFILES http://www.aerofiles.com/glossary.html

VORTAC:

VOR + TACAN (Tactical Air Navigation); combined radio navigation aids.

AEROFILES http://www.aerofiles.com/glossary.html

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Wavelength:

The physical distance between identical points on successive waves.

http://www.bradleyairport.com/community/noise-glossary.php

White Noise:

Broadband noise across the whole audio spectrum that contains an equal amount of energy in all frequencies when measured on a linear frequency scale.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

World Health Organization (WHO):

The World Health Organization (WHO) is the directing and coordinating authority for health within the United Nations system. It is responsible for providing leadership on global health matters, shaping the health research agenda, setting norms and standards, articulating evidence-based policy options, providing technical support to countries and monitoring and assessing health trends.

http://www.euro.who.int/Noise

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`Z'Weighting:

The "zero" or un-weighted frequency correction curve corresponding to the Linear setting on some instruments.

Glossary of Common Noise Terminology http://www.casellausa.com/store/page.cfm?pageID=79504A404E

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