Reliable Robotics adds $115M to its Series D, lifting the round to $275M at a valuation above $1B

TLDR

• Reliable Robotics raised $115M, upsizing its Series D to $275M and pushing its valuation past $1B.¹²
• Nimble Partners led as a returning investor; the $115M includes a $25M Silicon Valley Bank term loan.¹²
• CEO Robert Rose expects FAA certification of its first system in 18 to 24 months, TechCrunch reports.²

Reliable Robotics, a Mountain View, California, company building certifiable autonomy for aircraft, announced on 20 October 2026 that it has raised $115 million in new capital.¹ The company says this upsizes its previously announced $160 million Series D because of investor demand, brings the round to $275 million and pushes its valuation above $1 billion.¹ The $115 million includes a $25 million term loan from Silicon Valley Bank, which TechCrunch separates out as $90 million of equity led by Nimble Partners plus $25 million of debt.¹² Reliable says it has now raised more than $380 million in equity; TechCrunch and GeekWire put total funding at $380 million.¹²³

Per the release, Nimble Partners led as a returning investor. Gideon Capital, RockCreek, Geek Ventures, Gold Hill Capital, Sparkwave Capital and others are new, and Island Green Partners continued as a returning investor.¹ Allen & Company supported the fundraise.¹ TechCrunch names the same group but calls the first new investor Gideon Strategic Partners rather than Gideon Capital; the sources do not resolve which is correct.¹²

Reliable's Reliable Autonomy System (RAS) and Reliable Radar are meant to prevent loss of control and controlled flight into terrain on existing, certified aircraft.¹ The company is certifying the RAS on the Cessna 208B Grand Caravan with the Federal Aviation Administration.¹ TechCrunch reports four certification fronts. Rose expects the first, continuous autopilot engagement with a pilot still aboard, in 18 to 24 months. He says moving the pilot to a ground station is at least three years away, and expects its in-house solid-state radar to be certified by the end of 2027. The fourth is for its own cargo airline, Reliable Airlines, which flies six Cessna Caravans out of Albuquerque.² GeekWire adds that the new money funds a radar centre of excellence in Bothell, Washington, with about 25 staff at opening, and a San Diego office focused on military autonomy.³

The release calls the RAS "a dual-use, safety-enhancing technology that has both commercial and military applicability". It says Reliable has contracts with multiple branches of the US military and has completed several military airworthiness reviews with the US Air Force.¹ The release does not name the contracts or their values, and the other sources reviewed do not confirm them.

On the lead: Nimble Partners is led by founder John Burbank, who told TechCrunch the opportunity is "a much bigger effort and much bigger opportunity than to just build one plane" and that approval of the first system would show the industry the path, as in autonomous cars.² The sources reviewed name no other autonomy or defence companies backed by Nimble, and none describe the portfolios of the new investors.

Why it matters: a unicorn valuation for a company still some 18 months from its first FAA certification shows investors pricing in the regulatory outcome, with the military use case offered as a second market that the sources do not substantiate.