An inspection crawler, and systems and methods for inspecting underwater pipelines are provided. The system includes the inspection crawler having a housing with a first side, an opposing second side, a power source, and a controller. The crawler includes an inspection tool, at least two pairs of latching arms, each latching arm including a rolling element, and at least two pairs of driving wheels. The system also includes at least one communication unit configured to communicate with the inspection crawler and to communicate aerially with one or more remote devices and, and at one sea surface unit. The inspection crawler can further include a connecting structure connecting the front and back portions of the crawler, and configured to elongate and shorten the inspection crawler.