Critical infrastructures are ubiquitous in the modern world and include electrical power systems, water, gas, and other utilities, as well as trains and transportation systems including airports. This work is concerned with Supervisory Control And Data Acquisition (SCADA) systems that are at the heart of distributed critical infrastructures within airports. Modern airports are highly competitive cost driven operations that offer a range of public and private services. Many airport systems such as car parking and building control systems are SCADA controlled. This is achieved with sensors and controllers monitored over a large, geographically disperse area. To increase efficiency and to achieve cost savings, SCADA systems are now being connected to information technology system networks using TCP/IP. The merging of SCADA systems into the main IT network backbone is presenting new security problems for IT security managers. Historically, proprietary solutions, closed systems, ad-hoc design and implementation, and long system life cycles have led to significant challenges in assessing the true security posture of SCADA systems. To address this, this work seeks how SCADA systems are being integrated into the IT network within a modern airport. From this new standpoint we will be able to identify ways in which SCADA may be vulnerable to malicious attack via the IT network. The results of this work could offer solutions to increase security within airports.