This study presents a solution for connecting system simulation and aircraft concept development using solely open standards. An easy-to-use optimisation framework for aircraft concept development is created with the help of the Modelica, Functional Mock-up Interface (FMI), and System Structure and Parameterization (SSP) standards, and the open source tools OpenModelica and OMSimulator. The framework allows for conceptual aircraft design accounting for transient phenomena by means of standardised integration of dynamic simulation models of aircraft subsystems. The framework is applied to an industry-relevant use case concerning the concept development of a generic fighter aircraft. The generality and modularity of the framework and its straightforward implementation enables tailoring of the optimisation goals to the user needs and requirements. The adoption of industry-wide standards allows for the inclusion of system simulation models developed in the modelling tool best suited for each discipline, thus integrating dynamic system simulation already at the aircraft conceptual design stage.