Timely and cost-effective acquisition of environmental and oceanographic data is critical to the success of naval, commercial, and scientific operations in the ocean. The measurement of the sound speed profile (SSP) in the marine environment is required for calibration of naval sonar systems engaged in undersea warfare (USW) operations. Current systems for SSP acquisition, including expendable bathythermographs (XBTs) and BT sonobuoys do not provide a persistent measurement capability or propulsion for navigation and station keeping. Underwater buoyancy glider systems are a proven technology for persistent sensing in the marine environment, with systems currently deployed around the world and in a variety of measurement applications, including naval oceanography, weather forecasting, and oil and gas environmental monitoring. These systems are often large, expensive and require surface vessels to support launch and recovery operations. The proposed Slocum-A glider system is an A-size sonobuoy launcher compatible buoyancy glider system that will enable persistent environmental and oceanographic measurements in a low-cost, compact, air-launchable form factor. The glider system will leverage class-leading Slocum glider technology and satellite communications to enable seamless exfiltration of measurement data to nearby vessels, as well as over the horizon to naval oceanographic, scientific, and commercial databases. In this SBIR we will design and develop the glider system by performing engineering and trade studies to develop miniaturized versions of Slocum glider components and assemblies and integrate these subsystems into a buoyancy glider system that is compatible with A-size sonobuoy launchers. The Slocum-A glider system will be equipped with sensors and communications technology capable of delivering SSP data to tactical decision aids on nearby vessels, and with a maximum operational depth of 200m.