Airport Noise and Land Use
Compatibility
FAR Part 150
AST 491
Background
National Environmental Policy Act of
1969 (NEPA)
 Aviation Noise Abatement Policy,
1976

» First identification between FAA,
Carriers, Operators and Communities of
the Responsibilities for Aircraft Noise
Impacts
Litigation Began
 Each person reacts differently to
sound/noise

Noise
Unattenuated Sound
 Sound of aircraft noise almost always
intrusive and unwanted
 John Linen -Music
 Rap - Noise

Levels of Sound
Most common measure is decibel (db)
 Logarithmic scale increasing by powers
of ten
 Perceived loudness doubles every
increase of ten db’s

Cumulative/Summation
Metrics
Should tell where affected, how many
people affected and how badly affected
 Needs to indicate cumulative noise
exposure

» a metric which considers all noise energy
received at a given location during a
defined period and averages the sum of the
average noise level per second
Cumulative/Summation
Metrics
Developed to define noise in a way
subject to objective analysis
 Previous techniques such as time
above, ASDS, and single event
correlation to human response

Cumulative/Summation
Metrics
Developed to correlate highly with
human response
 Equal Energy Rule

» Over a given period of time, people
respond most predictably to the total
noise level energy rather than to the
characteristics of any single noise event
Ldn : Day-Night Average
Sound Level
The average sound level during a
twenty-four hour period with a 10
decibel penalty for nighttime noise
events.
 The basic element of measure is the
Sound Exposure Level (SEL)
 Simply adds all noise levels for each
second of the day and averages the
summation on an equal basis.

Ldn : Day-Night Average
Sound Level
Human response to noise is intensified
during nighttime hours. Response is so
much greater that it must be treated
differently.
 Nighttime events (10:00 pm to 7:00
am) are penalized by adding ten
decibels to the measurement of each
event.

Noise Contours
Ldn levels are calculated for specific
locations. The contours connect points
of equal intensity.
 Ldn contours most commonly used
are Ldn 65,70 and 75. Also mandated
by FAA Regulation (FAR PART 150)

FAA FAR PART 150
Background

1976 Aviation Noise Abatement Policy
» voluntary ANCLUC Studies
DOD Air Installations Compatible Use
Zones (AICUZ)
 Aviation Safety and Noise Abatement
Act of 1979 (ANSA).

» directed FAA to set forth procedures for
noise and land use compatibility.
– started FAA FAR Part 150
ANSA- Aviation Safety and
Noise Abatement

Section 102 - Single system of
measuring noise
» identifies land use use compatibilities

Section 103 - Funding set aside for
noise mitigation and planning
» first time ever in federal legislation

Section 104 - Requirements for noise
compatibility
ANSA- Aviation Safety and
Noise Abatement
Section 105 - Requirements for noise
exposure maps (NEM)
 Section 106 - Use of NEM as evidence
to suits

» seeking damages prohibited
» airport can not use to defend
ANSA- Aviation Safety and
Noise Abatement

Section 107 - Limits damages with
respect to approved NEM
» farmers can not sue
Section 108 - FAA studies process and
reports back to congress
 If airport plans study, it must give public
“constructive Notice” by advertising in
the newspaper 3 times

Components of a Part 150
Study

Two Final Products
» Noise Exposure Map
» Noise Compatibility Plan
Noise Exposure Map
Show unabated noise exposure in
Ldn for existing year and fifth year
following date of submission
 Maps must show incompatible land use,
discussion of activity forecasts
 Assumptions upon which contours are
based
 explain noise monitoring, if done.

Noise Exposure Map

Analysis of background noise: if
incompatible land uses are impacted by
high levels of ambient noise levels then
not considered impacted by aviation
noise.
Noise Exposure Map
Noise exposure maps document
submitted for review and “approval” by
the FAA
 Section 107 of ANSA: Once NEMs are
approved then it limits liability to recover
noise related damages.

Noise Exposure Map
Subsequent land owners must show
significant change in the noise
environment after constructive
knowledge of maps. (normally at
least 15% change), usually within the
65 Ldn contour line.
 Constructive knowledge means
published in paper 3 times-notice that
maps are in existence.

Noise Compatibility Program
Discussion of analysis of noise
abatement and land use management
measures that are specifically listed in
the regulation. Other measures may be
evaluated.
 The plan should provide for noise
abatement through modification of flight
procedures, regulations and even the
airfield.

Noise Compatibility Program
Includes land use provisions to reduce
existing noise impacts and prevent
future noise impacts.
 The NCP must be developed in
consultation with airport users and
jurisdictions in the area.
 Public must be afforded an opportunity
to comment on the study - opportunity
for public hearing - always plan on one.

Noise Compatibility Program
Airport proprietors decision to
submit. No penalties for not
submitting. FAA will review for
completeness and publish Notice in
the Federal Register. This notice sets
the 180 day time frame.
 FAA has 180 days to reject NCP.

Noise Compatibility Program
Approved plan makes airport eligible for
funds from noise set aside of AIP. Only
eligible items of the NCP can be funded.
 NEM - no time limit for the FAA to
approve.

Standards of Review for
Approval

The FAR Part 150 NCP must:
» Contain measures which are reasonably
consistent with goal of preventing and
reducing noncompatible land use.

Not derogate safety or adversely affect
use of airspace.
Noise Compatibility Program

The FAR Part 150 NCP must:
» Meet both local and national air
transportation system needs.
» Provide for revision every 5 years (if
necessary)
» Not adversely affect any other powers,
duties, program, etc.
Technical and Economic Data
Required by the FAA
NEM and supporting documentation.
 Description and analysis of alternatives
considered by implementation authority.
 Discussion of rejected alternatives and
why.
 Development of program that meets
FAA standards.

Noise Compatibility Program
Requirements
Actual or anticipated effect on reducing
noise exposure.
 How it may change previously adopted
plans or actions.
 Time Frame.
 Responsible parties.

Noise Compatibility Program
Requirements
Costs of the program
 Provision for revising program if
necessary
 Description of public involvement.

Alternatives Required for
Consideration
Acquisition of land or interest herein.
 Barriers/Shielding/Sound Proofing and
noise easements.
 Preferential runway use system by FAA.
 Flight procedure changes by FAA
 Restriction on use of airport.
 Other actions by FAA or others.

Other Measures
Airport Development measures.
 Navigational aids.
 Off-airport land use controls.
 Noise Monitoring
 Administrative measures and studies.

Airport Use Restrictions
Must be reasonably consistent with
reducing non-compatible land use, must
not create an undue (unreasonable)
burden to interstate commerce, must not
unjustly discriminate, nor derogate
safety.
 Airport use restrictions are extremely
variable.

Airport Use Restrictions
Most significant impact occurs when a
restriction adversely affects airport
capacity and/or excludes certain users
from the airport.
 Must present magnitude of capacity
impacts versus demand impact and the
affect of excluding aircraft types.

Airport Use Restrictions

Analysis of impact on interstate
commerce would consider such things
as markets served, or cargo served,
costs of rescheduling service at the
airport, alternative airport available in
the area.
» not yet been done in the U.S.
Airport Use Restrictions

For instance: a nighttime restriction on
stage 2 aircraft would include
considerations of available stage 3
aircraft, shift of flights to daytime hours
daytime capacity and alternative airports
at night.
Land Use Controls
Zoning
 Easement

» Avigation - Runway Protection Zone (RPZ)
» Noise (exact easements)
» Transfer of development rights
– enabling legislation
– Comprehensive planning
Land Use Controls
Subdivision regulations
 Building codes

» sound proofing to 30 db’s
Review and Approval Process

First reviewed at regional level. (both
NCP/NEM)
» Knowledge of local noise and land use
situations.
» NEM final approval level is Region

Then goes to Washington for review and
approval. (only NCP)
» National Consistency of FAA Determination.
Review and Approval Process

Each measure is recommended for
approval or disapproval.
» final authority is with the administrator.

It is a local program.
» not a federal program
Review and Approval Process

NEM’s can be approved at FAA
Regional Level.
» NCP must be approved/disapproved within
180 days of NEM acceptance.
When to do a Part 150
Significant amounts of incompatible land
use impacted by aircraft noise.
 Serious noise complaints received.
 Urban development pressure threatens
to increase incompatible land uses.
 Major changes in airport facilities or
aircraft operations which may shift noise
patterns.

Advantages of Part 150
Public relations
 Intergovernmental coordination
 Airport facilities development.
 Improved land use planning.
 Noise abatement.

Disadvantages of Part 150
Heightened controversy.
 Unrealistic expectations.
 Uncooperative participants in process.
 Litigation possible.

Summary

An FAR Part 150 Study can be an
important means of improving noise and
land use compatibility with the airport
environs while achieving other
objectives that are important to the
airport and local governments. The
process is not without risks and pitfalls;
however, it must not be seen as a
panacea for airports with noise and
public relations problems.