Current ocean sensing platforms are constrained by high costs, limited scalability, and insufficient data resolution—particularly for capturing submesoscale ocean dynamics that are vital for understanding ocean mixing and climate. This project proposes the development of CALANOID, a modular, low-cost, air-deployable ocean profiling float system, designed to enable dense, distributed in-situ observations. This project fosters collaboration between industry and academia and supports workforce development through hands-on engineering and research opportunities. The open-standard design ensures extensibility and accessibility for the broader scientific community, contributing to open science and equitable participation in global ocean research efforts. The project advances the state of the art in ocean sensing technology through the design and validation of a modular, scalable profiling platform that addresses critical gaps in spatial and temporal resolution of submesoscale measurements. Key innovations include a compact, piston-cylinder buoyancy engine designed for precise vertical profiling, and the NanoCTD, a miniaturized, and a solid-state CTD sensor. The integration of low-cost MEMS-based temperature and pressure sensors further enhances data quality while maintaining affordability. The system is designed to meet stringent performance targets, including 400-meter pressure ratings and two-month operational endurance, and will be validated through rigorous lab and field tes