DiamondStream Partners is a venture capital firm based in Seattle that invests in middle-stage aerospace, aviation, mobility, and related hardware and software companies across the United States, Europe, and other English-speaking markets. It emphasizes next-generation mobility and disruptive aviation technologies, backing opportunities that lower costs, improve efficiency, and address unmet needs in both established and emerging markets such as aerial mobility, electric propulsion, and AI-driven predictive maintenance. Its portfolio includes Elroy Air, Ampaire, GPMS International, and Wingtra, illustrating a focus on autonomous aircraft, electrification, predictive maintenance, and drone inspection solutions. The managing partners are aviation experts who co-founded Volaris and bring investing, technology, and operating experience, applying a vertical industry approach informed by drivers of industry demand. Founded in 2003, DiamondStream pursues middle-stage investments in aerospace, aviation, and related software and hardware across the US, Europe, and other English-speaking regions.