represents the main part of the investment necessary,
surpassing even the initial investment calculated for
the operations. This amount can be vital for a
company of the scale of the one studied (Bercovitz
and Mitchell, 2007). In addition to this, the selection
process was also shown to be complex at the
beginning, given the number of criteria and their
variations of measurement as well as the quantity of
alternatives to be chosen.
The adoption of a multicriteria decision aiding
tool, providing the managers with well-grounded
decision making, is justified therefore by the
importance for the company and the complexity of
the decision making problem. As it belongs to an
economic group, the decision was the responsibility
of the president of the group. The information
passed on to the decision analyst originates above all
from internal research, with the director of
operations also responsible for the evaluation of the
value of the qualitative variables necessary to the
process and which would be treated by means of
fuzzy logic (Zadeh, 1975).
It fell to these two agents, assisted by the
decision analyst, to make the definition of the set of
alternatives and the family of criteria. To help in
solving the problem, a multicriteria decision aiding
method was chosen with qualities more aligned to
those which the problem required. The actors that
participated in the process were the managers of the
company. The multicriteria method chosen is the
NAIADE method, created by Munda (1995). This
method encompasses, to a greater or lesser degree,
characteristics of resistance to trade-offs – in
contrast, for example, to MAUT, in which there is
an explicit exchange between values in a
multiattribute utility function (Keeney and Raiffa,
1976) – and the possibility of the application of
variables of diverse types. According to Munda
(1995), the application of the NAIADE method
consists of three steps: pair comparison, aggregation
of the criteria and the analysis of the alternatives.
For the application of the first step, the
difference of values between the alternatives must be
obtained. The way in which this difference is
obtained constitutes the larger part of the foundation
of the method. For this reason, even before knowing
how each one of the three steps is executed,
attention must be given to the functioning of this
mechanism.
In the literature there are already some uses of
MCDA in Air Transportation. For instance, a high
density route, the Belgrade – Zagreb air shuttle
service was evaluated by Teodorović (1985) using
the TOPSIS method, and another high density route,
the Rio de Janeiro – São Paulo was evaluated by
Soares de Mello et al (2003) using the MACBETH
method (Bana e Costa and Vansnick, 1994).
2 METHODOLOGY
ANAC – the National Agency of Civil Aviation is
the Brazilian authority responsible for the regulation
of air transport. Constituted by Law no. 11.182,
ANAC regulates the sector supported by the
Brazilian Aeronautical Code and specific
regulations, called the Brazilian Regulations of
Aeronautic – RBHA. According to the RBHA 119
and 135, aircraft permitted for regional charter
operations are those with a capacity equal to or less
than 30 passengers, which already significantly
limits the viable alternatives. Also according to these
regulations, some advantages can be obtained by
companies which opt to use aircraft with a capacity
equal to or less than 19 passengers. The main
advantage can be found in RBHA 135.3(b), where
the company is dispensed from more detailed
training of the crew. Another significant advantage
can be found in RBHA 135.107, which dispenses the
company from the need for a qualified steward on
board its flights, which significantly reduces the
operational costs, of training, and of the preparation
and maintaining of the documents necessary for
operations.
With this new cut-off, the universe of choices
was reduced even more. According to the managers
of the company, the alternatives to be evaluated are:
Cessna Caravan, Fairchild Metro, Beechcraft 1900,
Embraer EMB-110 Bandeirante, LET 410, De
Havilland DHC 6, Dornier 228 and the CASA 212.
In relation to the criteria, one of the ways of working
with the definition of the criteria is by creating a
hierarchy in the form of a tree, in this way becoming
very similar to the AHP method (Saaty, 2005). At
the higher levels are the more wide ranging criteria
which are subdivided in other more detailed criteria
until a sufficiently specific family of criteria is
formed which can be evaluated effectively.
At the first level the criteria are divided into
three groups. In the financial group, there are the
criteria which result in direct expense or which
produce some impact on the financial or economic
administration of the institution. In the group of
criteria linked to logistics are listed the criteria
which are most significant for the operation of the
aircraft and their limitations. Lastly, in the group
linked to quality, the criteria reflect, either directly
or indirectly, the level of relative satisfaction on the
ICORES 2012 - 1st International Conference on Operations Research and Enterprise Systems
428