791 

Federal Aviation Administration, DOT 

§ 161.5 

U.S.C. App. 2153, 2154, 2155, and 2156). It 
prescribes: 

(a) Notice requirements and proce-

dures for airport operators imple-
menting Stage 3 aircraft noise and ac-
cess restrictions pursuant to agree-
ments between airport operators and 
aircraft operators; 

(b) Analysis and notice requirements 

for airport operators proposing Stage 2 
aircraft noise and access restrictions; 

(c) Notice, review, and approval re-

quirements for airport operators pro-
posing Stage 3 aircraft noise and access 
restrictions; and 

(d) Procedures for Federal Aviation 

Administration reevaluation of agree-
ments containing restrictions on Stage 
3 aircraft operations and of aircraft 
noise and access restrictions affecting 
Stage 3 aircraft operations imposed by 
airport operators. 

§ 161.3 Applicability. 

(a) This part applies to airports im-

posing restrictions on Stage 2 aircraft 
operations proposed after October 1, 
1990, and to airports imposing restric-
tions on Stage 3 aircraft operations 
that became effective after October 1, 
1990. 

(b) This part also applies to airports 

enacting amendments to airport noise 
and access restrictions in effect on Oc-
tober 1, 1990, but amended after that 
date, where the amendment reduces or 
limits aircraft operations or affects 
aircraft safety. 

(c) The notice, review, and approval 

requirements set forth in this part 
apply to all airports imposing noise or 
access restrictions as defined in § 161.5 
of this part. 

§ 161.5 Definitions. 

For the purposes of this part, the fol-

lowing definitions apply: 

Agreement 

means a document in writ-

ing signed by the airport operator; 
those aircraft operators currently oper-
ating at the airport that would be af-
fected by the noise or access restric-
tion; and all affected new entrants 
planning to provide new air service 
within 180 days of the effective date of 
the restriction that have submitted to 
the airport operator a plan of oper-
ations and notice of agreement to the 
restriction. 

Aircraft operator, 

for purposes of this 

part, means any owner of an aircraft 
that operates the aircraft, i.e., uses, 
causes to use, or authorizes the use of 
the aircraft; or in the case of a leased 
aircraft, any lessee that operates the 
aircraft pursuant to a lease. As used in 
this part, aircraft operator also means 
any representative of the aircraft 
owner, or in the case of a leased air-
craft, any representative of the lessee 
empowered to enter into agreements 
with the airport operator regarding use 
of the airport by an aircraft. 

Airport 

means any area of land or 

water, including any heliport, that is 
used or intended to be used for the 
landing and takeoff of aircraft, and any 
appurtenant areas that are used or in-
tended to be used for airport buildings 
or other airport facilities or rights-of- 
way, together with all airport build-
ings and facilities located thereon. 

Airport noise study area 

means that 

area surrounding the airport within 
the noise contour selected by the appli-
cant for study and must include the 
noise contours required to be developed 
for noise exposure maps specified in 14 
CFR part 150. 

Airport operator 

means the airport 

proprietor. 

Aviation user class 

means the fol-

lowing categories of aircraft operators: 
air carriers operating under parts 121 
or 129 of this chapter; commuters and 
other carriers operating under part 135 
of this chapter; general aviation, mili-
tary, or government operations. 

Day-night average sound level (DNL) 

means the 24-hour average sound level, 
in decibels, for the period from mid-
night to midnight, obtained after the 
addition of ten decibels to sound levels 
for the periods between midnight and 7 
a.m., and between 10 p.m. and mid-
night, local time, as defined in 14 CFR 
part 150. (The scientific notation for 
DNL is L

dn

). 

Noise or access restrictions 

means re-

strictions (including but not limited to 
provisions of ordinances and leases) af-
fecting access or noise that affect the 
operations of Stage 2 or Stage 3 air-
craft, such as limits on the noise gen-
erated on either a single-event or cu-
mulative basis; a limit, direct or indi-
rect, on the total number of Stage 2 or 
Stage 3 aircraft operations; a noise