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Aircraft Technology & Cost Module

The Aircraft Technology & Cost Module is required to estimate aircraft fuel use and emissions for given technologies under specified conditions. This module also estimates the costs associated with the ownership and operation of these aircraft. At this stage, the module is based on previously-developed capabilities from the Cambridge University Engineering Department based on simple technology and aircraft performance models. ICAO emissions indices for existing engine technologies are being used to parameterise the effects of technology evolutions.

Further AIM-specific development of the module is involving four sub-models.

The Aircraft Performance Model captures performance aspects of aircraft during typical “gate-to-gate” flight phases, while the Aircraft Technology Model predicts evolutions in aircraft technology (both airframe and engine) and their phase-in to the air transportation system. These models are coupled to a

Fuel Use & Emissions Model which calculates fuel consumption and associated emissions production for the various technology levels during the modelled flight phases.  The technology and fuel use characteristics are used in the Aircraft Cost Model in order to calculate the operating costs impacts. To obtain a sufficiently good representation of the spectrum of aircraft technologies operating within the global air traffic network, these models consider multiple classes of aircraft covering different size, range and age categories.

The Fuel Use & Emissions Model interfaces with the Airport Activity and Aircraft Movement Modules, outputting emissions (CO2, NOx, CO, UHC and PM) as a function of flight phase and aircraft class. The Airport Activity Module utilises emissions during the Landing and Take Off (LTO) flight phases (including engine idling while stationary on the ground, taxiing from the terminal area, taking off to 3000 ft, landing from 3000 ft and taxiing back to the terminal area), while the Aircraft Movement Module utilises the data for flight operations above 3000 ft (climb, cruise, descent and airborne holding).

The internal Aircraft Cost Model interfaces with the Air Transport Demand and Airport Activity Modules, outputting ownership and operation costs based upon exogenously specified technology trajectories. In future versions of AIM, this module’s cost model will identify the least-cost aircraft technology (mainly characterized by emissions and direct operating costs) to each of the aircraft classes, using a net present value analysis. It will also be hard linked to an aircraft stock model. Inputs into that estimation are expected fuel prices along with all other determinants of direct operating costs.  The resulting costs are marked up and passed on to the Air Transport Demand Module in terms of prices per passenger-km travelled. (A more complex iteration loop between this model, the Air Transport Demand Module, and the Airport Activity Module rebalances air travel demand with the ticket price consequences of technology and operating costs, but this will not be discussed in detail here).

The module is designed to take as input various policy options and technology developments aimed at reducing the environmental impact of air transport. These include:

  • Certification and regulatory pressures affecting airframe and engine technology evolution paths
  • Economic instruments affecting direct operating costs (e.g. fuel taxation and emissions charges)
  • Ownership and operating costs of new and novel engine and airframe configurations