Project planning and scheduling professionals use a variety of project scheduling methods depending on the type, size, and nature of projects. Linear scheduling methods (LSM) are typically used on projects wherein the majority of the scope is made up of highly repetitive work elements along a horizontal or vertical alignment. Examples of these projects include pipeline, tunnel, airport runway, highway, transmission line, road resurfacing, railroad, or high-rise construction projects. An LSM schedule (also known as a linear schedule, march chart, or time chainage diagram) is the graphical output of the LSM. Linear schedules use velocity diagrams, which are described below, to represent each activity and the progress rate to be achieved (or the progress actually achieved) over time. The schedule format typically provides planned and/or actual production rates on a time-scaled, linear format.
This recommended practice (RP) is intended to serve as a guideline, not a standard. As a recommended practice of AACE International, the main objectives of this recommended practice (RP) are to increase LSM usage and enhance project management practices by:

• Providing an overview of the LSM.
• Defining characteristics and applications of the LSM.
• Delineating the steps and main considerations in developing, updating, and managing linear schedules.
• Highlighting main considerations in interpreting linear schedules.