Source - Vi.potsdam.ny.us - Potsdam

Potsdam Municipal Airport - Master Plan – Phase 1 Report
2.02-3 Navigational Aids
Aircraft navigating from one airport to another operate use Visual Flight Rules (VFR)
or Instrument Flight Rules (IFR). The term VFR refers to rules that govern the
procedures for conducting flight under visual conditions. The term IFR refers to a set
of rules governing the conduct of flight under instrument meteorological conditions.
Each of these terms is also used to indicate a type of flight plan.
Whether a pilot files a VFR or IFR flight plan depends on the weather conditions at
the departing and arriving airports, whether or not Air Traffic Control (ATC) services
are required, and the class(es) of airspace the pilot will be flying through. For
example, all aircraft flying in Class A airspace (above 18,000 feet MSL) must file an
IFR flight plan. As a result, most commercial activity is conducted under an IFR
flight plan. Aircraft flying IFR rely on navigational aids for en route navigation from
origin to destination, and on final approach to an airport.
INSTRUMENT APPROACH PROCEDURES
An Instrument Approach Procedure (IAP) is a flight procedure that provides a
transition from the enroute flight environment to a point from which a safe landing
can be accomplished. When the cloud ceilings are low and visibility is poor, flights
must use published IAPs when transitioning to the landing environment. The FAA
has established ceiling and visibility minimums by category of aircraft for each IAP
at an airport. Currently there are two non-precision IAPs for Runway 24 at Potsdam
Municipal Airport.
Table 2-6 is a summary of the approaches available at the Airport. It should be noted
that the landing minimums listed are based upon full operation of all components and
visual aids associated with the particular instrument approach. Higher minimums are
required with inoperative components or visual aids. The first number for each
aircraft category is the Decision Height – a specified height above the threshold
elevation in the precision approach at which a missed approach must be initiated if
the required visual reference to continue the approach has not been established. The
second number is the required visibility for the approach in statute miles.
TABLE 2-6
INSTRUMENT APPROACH PROCEDURES
Aircraft Approach Category
Approach A B C D
NDB Runway 24 920-1 920- 1 ¼ NA
NDB Runway 24 (Circling) 920-1 1040-1 1040- 1 ½ NA
RNAV GPS Runway 24 (LNAV MDA) 880- 1 880- 1 ¼ NA
RNAV GPS Runway 24 (Circling) 880-1 1040- 1 1040- 1 ½ NA
Source: Northeast U.S. Terminal Procedures – Instrument Approach Procedures (2009)
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