Method for technical and economic evaluation of the effectiveness of reliability improvement of military aircraft gas-turbine engines in their aftersales support based on outcome performance measures

The article describes a conflict between interests of the state customer and the prime contractor on the issue of aeronautical systems and subsystems reliability improvement during its aftersales support. The conflict between interests is shown to arise under the traditional approach to payment for the prime contractor’s services on a basis called “costs+”. Contractual models of public-and-private partnership which are used in the foreign countries successfully, with a payment scheme for the contractor’s services based on outcome performance measures of aeronautical systems and subsystems aftersales support, are presented as a conflict settlement mechanism. A long validity term of such contracts and independence of performance payment amounts from the contractor’s actual expenses motivate the private partner to hold some activities aiming at systems and subsystems reliability improvement. Applicability of technical and economic assessment of these activities is demonstrated. The main provisions of the method for technical and economic evaluation of the effectiveness of aeronautical systems and subsystems reliability improvement are presented thorough the example of a fleet of engines operated within a group of military transport aircrafts with their aftersales support based on outcome performance measures. The method is based on a simulation model of engines fleet operating which allows for the measures of technical and economic evaluation to be identified: average availability of the military transport aircrafts group during the contract validity period, state customer’s operating costs and the prime contractor’s profit. It is experimentally shown on the developed method basis that when the fleet of engines is supported aftersales based on outcome performance measures the prime contractor has an economic interest to improve engines reliability above the requirements specified in the regulatory documentation.