Page 197 - Planning and Design of Airports

164 Airp o r t Pl anning

The Airport System Plan
The purpose of an airport system plan is to identify the aviation devel-
opment required to meet the immediate and future aviation needs of
a region, state, or metropolitan area [17]. It recommends the general
location and characteristics of new and expanded airports, shows the
timing, phasing, and estimated cost of development, and identifies
revenue sources and legislation for the implementation of the plan.
The aviation system plan also provides a basis for the definitive and
detailed development of the individual airports in the system.
The primary forecasting requirement for the airport system plan
is a projection of the level of aviation activity during the planning
period. The forecasts are usually made on an annual basis for the
planning entity as a whole and are then proportioned among the var-
ious individual airports within this entity. Specific projections are
generally made for total aircraft operations, air carrier and general
aviation operations, based aircraft, total air cargo, and passenger
enplanements for the short-, medium-, and long-range time frames
within the planning period. These demand projections are compared
to the inventory of physical facilities to determine development
needs. It should be emphasized that these projections are normally
made in a very aggregate fashion and tend to examine overall deter-
minates of regional activity rather than the specific factors affecting
local activity.
The preparation of a forecast for a system plan is initiated by the
collection of historical data indicative of the various components of
aviation activity. These data normally include broad measures of
socioeconomic activity as well as aviation activity statistics. Due to
the fact that data collection is very expensive, most of the data collec-
tion in a system plan depends primarily on secondary or existing
sources and very little survey work is performed. Many of the overall
regional projections are made on the basis of trend projections or sim-
ple econometric models and these are then apportioned to the indi-
vidual airports within the region on the basis of ratio methods. In the
analysis of observed trends and the preparation of future forecasts,
broad indicators are generally used including an examination of the
consistency and realization of past trends and a comparison of growth
rates and economic indicators.

The Airport Master Plan
The purpose of the airport master plan is to provide the specific
details for the future development of an individual airport to satisfy
aviation needs consistent with community objectives. The airport
master plan requires detailed projections of the level of demand on
the various facilities associated with the airport. Various concepts
and alternatives for development are examined and evaluated, and
recommendations are made relative to the prioritizing, scheduling,