Using Portable Navigation Systems (PNS)requires specially constructed interface while navigating in confined areas. User interface must be optimal according to its layout and navigational information shown on it. There is also a need to analyze which information on the electronic chart is indispensable and which may be removed, without affecting the system's usability.
Ergonomics and usability engineering gives appropriate tools to develop, veryfi and test optimal user interface. The paper presents main testing methods of user interface in PNS. Methods of electronic chart selection have been show. Before using the interface in real conditions, serval tests were conducted and the paper presents the respectively.