814 

14 CFR Ch. I (1–1–24 Edition) 

§ 170.11 

observed air traffic which may be in 
such proximity to the position or in-
tended route of flight of their aircraft 
to warrant attention. 

Traffic pattern 

means the flow of air-

craft operating on and in the vicinity 
of an airport during specified wind con-
ditions as established by appropriate 
authority. 

VFR traffic 

means aircraft operated 

solely in accordance with Visual Flight 
Rules. 

Visual flight rules 

(VFR) means rules 

that govern the procedures for con-
ducting flight under visual conditions. 
The term ‘‘VFR’’ is also used in the 
United States to indicate weather con-
ditions that are equal to or greater 
than minimum VFR requirements. In 
addition, ‘‘VFR’’ is used by pilots and 
controllers to indicate the type of 
flight plan. 

Visual meteorological conditions 

(VMC) 

means meteorological conditions ex-
pressed in terms of visibility, distance 
from clouds, and ceiling equal to or 
better than specified minima. 

[56 FR 341, Jan. 3, 1991, as amended by Amdt. 
170–3, 66 FR 21067, Apr. 27, 2001; Docket FAA– 
2017–0733, Amdt. 170–4, 82 FR 34400, July 25, 
2017] 

Subpart B—Airport Traffic Control 

Towers 

§ 170.11 Scope. 

This subpart sets forth establishment 

and discontinuance criteria for Airport 
Traffic Control Towers. 

§ 170.13 Airport Traffic Control Tower 

(ATCT) establishment criteria. 

(a) The following criteria along with 

general facility establishment stand-
ards must be met before an airport can 
qualify for an ATCT: 

(1) The airport, whether publicly or 

privately owned, must be open to and 
available for use by the public as de-
fined in the Airport and Airway Im-
provement Act of 1982; 

(2) The airport must be recognized by 

and contained within the National 
Plan of Integrated Airport Systems; 

(3) The airport owners/authorities 

must have entered into appropriate as-
surances and covenants to guarantee 
that the airport will continue in oper-
ation for a long enough period to per-

mit the amortization of the ATCT in-
vestment; 

(4) The FAA must be furnished appro-

priate land without cost for construc-
tion of the ATCT; and 

(5) The airport must meet the ben-

efit-cost ratio criteria specified herein 
utilizing three consecutive FAA annual 
counts and projections of future traffic 
during the expected life of the tower fa-
cility. (An FAA annual count is a fiscal 
year or a calendar year activity sum-
mary. Where actual traffic counts are 
unavailable or not recorded, ade-
quately documented FAA estimates of 
the scheduled and nonscheduled activ-
ity may be used.) 

(b) An airport meets the establish-

ment criteria when it satisfies para-
graphs (a)(1) through (a)(5) of this sec-
tion and its benefit-cost ratio equals or 
exceeds one. As defined in § 170.3 of this 
part, the benefit-cost ratio is the ratio 
of the present value of the ATCT life 
cycle benefits (BPV) to the present 
value of ATCT life cycle costs (CPV). 

BPV/CPV

≥

1.0 

(c) The satisfaction of all the criteria 

listed in this section does not guar-
antee that the airport will receive an 
ATCT. 

§ 170.15 ATCT discontinuance criteria. 

An ATCT will be subject to dis-

continuance when the continued oper-
ation and maintenance costs less ter-
mination costs (CMPV) of the ATCT 
exceed the present value of its remain-
ing life-cycle benefits (BPV): 

BPV/CMPV<1.0 

Subpart C 

[

Reserved

] 

PART 171—NON-FEDERAL 

NAVIGATION FACILITIES 

Subpart A—VOR Facilities 

Sec. 
171.1

Scope. 

171.3

Requests for IFR procedure. 

171.5

Minimum requirements for approval. 

171.7

Performance requirements. 

171.9

Installation requirements. 

171.11

Maintenance and operations require-

ments. 

171.13

Reports.