Directional drilling is a trenchless technology that allows contractors to install underground utilities—such as fiber optic cables—without digging large trenches. Drilling holes for fiber optics may seem like a daunting task, but with the right tools and techniques, it can be a surprisingly simple and efficient process. Here's how it typically works: Planning: The process starts with careful planning, including surveying. While traditional trenching has been used for decades, Horizontal Directional Drilling (HDD)—also called directional drilling—is now the preferred solution for many fiber optic projects. FO-VC2 JOINT USE - VERICAL MIDSPAN CLEARANCES 48.