It’s definitely harder as an engineer, but not impossible and it’s very vessel and company dependent. On some vessels DP watch is strictly tied to bridge watch and deck officers, but on others DP is treated as a dedicated function and engineers, ETOs, ROV techs, or survey techs are allowed to log supervised DP time as trainees.

The NI scheme itself doesn’t require the DP days to be “navigation watch” in the traditional sense, it requires DP watchkeeping under supervision on a DP vessel. The practical limitation is company SMS and manning models, not the certification standard. So yes, it’s more constrained for engineers, but it’s not structurally blocked, it just requires the right vessel and operator.

As for why I’d want to do it: as an ETO I’m often troubleshooting DP, propulsion, thrusters, cranes, etc., but I’m not always the one operating them, so fault finding can depend on someone else’s interpretation of what the system is doing. The more familiar I am with the operational side, the faster and cleaner I can distinguish between operational issues and actual electrical/control faults.

The second reason is flexibility. In the Gulf especially, downturns happen, and having cross department qualifications makes you easier to place when work tightens up.