Pilots currently use paper-based documentation and electronic systems to help them perform procedures to ensure safety, efficiency and comfort on commercial aircrafts. Management of interconnections among paper-based operational documents can be a challenge for pilots, especially when time pressure is high in normal, abnormal, and emergency situations. This dissertation is a contribution to the design of an Onboard Context-Sensitive Information System (OCSIS), which was developed on a tablet. The claim is that the use of con-textual information facilitates access to appropriate operational content at the right time either automatically or on demand. OCSIS was tested using human-in-the-loop simulations that involved professional pilots in the Airbus 320 cockpit simulator. First results are encouraging that show OCSIS can be usable and useful for operational information access. More specifically, context-sensitivity contributes to simplify this access (i.e., appropriate operational information is provided at the right time in the right format. In addition, OCSIS provides other features that paper-based documents do not have, such as procedure execution status after an interruption. Also, the fact that several calculations are automatically done by OCSIS tends to decrease the pilot's task demand .Read less <