Ditching is also accomplished with a rocsaw, which consists of a long chain arm with specially hardened teeth mounted on a D-9 caterpillar body. It resembles a giant chainsaw., 1977-04, PCA0002-4b-7, Folder: PCA0002-4b. Alyeska Pipeline Service Company : Trans-Alaska Pipeline Construction Collection, 1976-1977, PCA 2. Alaska State Library - Historical Collections Finding Aids. https://alaska.libraryhost.com/repositories/2/archival_objects/17799 Accessed February 22, 2025.