Metric 2: Aircraft Taxi Time
The second metric is the sum of unimpeded taxi time and
taxi delay. The unimpeded taxi time for an arrival is the time
taken for an aircraft to taxi from a spot to a gate when
congestion or other taxi impediments are not present. The taxi
time from a spot to a gate is calculated by dividing the distance
from a spot to a gate by the taxi speed. The unimpeded taxi
time for a departure is the time needed by an aircraft to taxi
from a gate to a spot when congestion or other taxi
impediments are not present. This unimpeded taxi time
includes the time needed for the aircraft to push back. This
study accounts for taxi delays that happen when either of the
following cases occurs. 1) A taxiing aircraft prevents another
aircraft from pushing back. 2) Two aircraft taxi in opposite
directions on the same taxi lane. The first case is called a pushback
blocking and the push-back is delayed until the taxiing
aircraft passes through the push-back route. The second case is
called a taxi blocking and one of the aircraft must shift its taxi
lane to another taxi lane; there are two parallel taxi lanes in the
ramp area at the airport of interest as shown in Fig. 2.
Therefore, taxi delays depend on the taxi routes of two aircraft.
Authors collected the taxi delay characteristics. Detailed
information is available in