In this work we present an Unmanned Aircraft Vehicle (UAV) designed from off-the-shelf components to release ocean mini-drifters. Its endurance (~ 1 h), payload (~5 kg), offshore range (30 km), capability of operating into wind conditions of ~10 knots, high precision autopilot (2-3 m), flying altitude of ~500 m above sea level, along with its relatively low cost (< 5,000 USD) enables quick and relatively easy oceanographic applications beyond 10 km offshore. We report here the very first successful ocean drifter releases, performed along the Baja California coast, between Tijuana and Rosarito, Mexico, and the technical details of the UAV. About fifty experiments (flights) allowed us to improve the take-off and landing, the release tunnel for mini-drifters, the cruise speed and altitude to release drifters safely, and to implement a parachute that controls the speed of the freefalling mini-drifters. Quick release of up to six drifters (armed with real-time data transfer and web-display) between 2 and 12 km offshore were performed at ~500 m above sea level, during a single flight in under 15 minutes, as opposed to classic techniques using boats or ships that, although can transport much more weight, can take several hours, use more human resources, and increase cost. Here we propose a novel open-source technique that can be used as a simplified method for scientific ocean measurements, as a quick-response emergency tool to map spills or for search and rescue.