Cost Index
The cost index (abbreviation: CI , German: cost index ) is a term from aviation and is mainly used in flight planning and management.
background
The flight planning of a specific flight can be carried out in favor of high performance or in favor of high cost efficiency in terms of consumption.
When planning in favor of high performance, in practice this results in a higher number of flights per accounting period, thus a higher turnover frequency and thus additional income for the airline. However, this also increases kerosene costs , which are dependent on the speed, as well as maintenance costs , which depend on the number of take-off and landing cycles.
When planning in favor of lower consumption, the number of flights per billing period decreases. The frequency of sales also decreases, albeit with constant fixed costs. Depending on the costs of kerosene, it can therefore be the case that the additional sales due to the more frequent flights in a performance-oriented flight are consumed by the additional costs of fuel and the maintenance cycle-dependent.
Since not all business cost accounts can be taken into account when planning a flight, these are reduced to a number, the so-called cost index. It describes the ideal balance between performance and fuel consumption and is determined by the airline. It is thus a measure of the planned economic efficiency of a flight and can be entered via the CDU (Control and Display Unit) into the FMS (Flight Management System), which calculates climb, travel and descent speeds, among other things.
definition
The CI is defined as follows:
| Cost Index = time-related costs in currency unit per flight hour / fuel price in currency unit per weight unit |
|---|
- Example at Airbus: ($ / flight minute) / ($ / kg of fuel)
- Example at Boeing: ($ / flight hour) / (US ¢ / lb of Fuel)
In other words, the cost index reflects the relative importance (relationship) of time-related flight costs to fuel costs.
The lower the CI, the higher either the fuel price and the associated costs or the flight hourly costs.
Depending on the aircraft or FMS manufacturer, various factors are weighted more or less heavily into the flight hour-related costs:
- the direct operating costs of the aircraft
- Cockpit crew
- Cabin crew
- Aircraft leasing costs
- Maintenance costs
- Aircraft material
- Aircraft maintenance work
- Engine material
- Engine maintenance work
- other costs
Calculating the CI is not easy because not all costs can be accurately predicted. For this reason, some airlines tend to rely on empirical values and estimate a certain CI for each aircraft type in a fleet. Others try to predict the costs as precisely as possible and calculate them individually for each flight.
A survey in November 2005 showed that most airlines use a flat CI per fleet.
