Heart Aerospace unveils 36-seat ES-36 as JSX commits to 50 aircraft

Why it matters

Heart has moved its regional-aircraft bet from a 30-seat design to the 36-seat ES-36, with JSX's deposit-backed commitment providing a customer partner. The cost and schedule claims remain unproven until the aircraft flies, certifies, and enters service.

Heart Aerospace unveiled the 36-seat ES-36 on September 23rd, alongside a deposit-backed purchase agreement for 50 aircraft with JSX and purchase rights for 50 more. The new model replaces Heart's ES-30 design with a larger cabin and revised hybrid-electric propulsion. The announcement appeared in Heart Aerospace's X post and the company's full release.

For founder and CEO Anders Forslund (@AndersForslund1), the redesign extends the bet that led him to start Heart: bringing electric propulsion to short-haul commercial flying. Forslund was working toward a PhD in aerospace product development when a period of research at MIT in 2013 helped shape that thesis. He later said, "Electrification is going to revolutionise aviation, and that's where I wanted to play," in an EQT Ventures account of Heart's early years. The company joined Y Combinator's W19 batch and has since moved from early aircraft concepts to flight testing a full-scale demonstrator.

The ES-36 keeps the ES-30's maximum takeoff weight and battery capacity, while Heart says it adds six seats and 1,415 pounds of payload capacity - a 20% increase in both. The company attributes that change to an aerodynamically revised airframe and a shift from four nacelles to two. Its proposed series-hybrid system uses electric motors to turn the propellers; batteries provide an all-electric range of 125 miles, plus reserves, while onboard gas-turbine generators extend the stated hybrid range to 745 miles, also plus reserves. Heart says those changes are intended to reduce maintenance and raise the aircraft's revenue capacity.

The operating-cost claim remains a target, not a demonstrated result. Heart says the ES-36 is designed to cost at least 40% less to operate than legacy regional aircraft. The aircraft has not flown: Heart says it is building the first pre-production unit at its Los Angeles pilot plant, expects a first flight in the second half of 2028, and targets entry into service in 2031 after FAA Part 25 certification. The company has not yet demonstrated the aircraft's commercial economics in service.

JSX gives the plan a potential launch customer with a specific use case. The carrier operates regional jets and turboprops and serves community airports; its CEO Alex Wilcox told Aviation Week that JSX sees opportunities on short routes such as Santa Monica to Santa Barbara. He described electric motors' lower exposure to repeated takeoff-and-landing cycles as an operating advantage. Under JSX's Part 135 certificate, the aircraft would be limited to 30 passenger seats, even though the design can carry 36, Aviation Week reported.

That detail puts the added capacity in perspective: JSX's commitment is to a tailored aircraft and operating model, not simply six more ticketed seats on every flight. Heart and JSX say they will work together on cabin layout, charging and turnaround procedures, route planning, and airport readiness. For JSX, the hybrid range could also let it use the aircraft where charging infrastructure is unavailable, while all-electric takeoffs could reduce noise at airports near communities.

The X1 demonstrator's first flight in August gave Heart a visible engineering milestone, but the ES-36 still has to move through prototype development, flight testing, and certification. Heart says the ES-36's design incorporates lessons from building and flying X1, which was developed as a demonstrator for the earlier ES-30. The production aircraft now changes the target configuration before that earlier design reached service. The company's ES-36 specifications describe the range and cost goals; the remaining test is whether Heart can certify the revised aircraft on its schedule and deliver the promised operating savings.

The JSX deal is deposit-backed and includes an additional 50 purchase rights, rather than an unconditional commitment for 100 delivered aircraft. Heart's release says the agreement converts a 2023 letter of intent into a purchase commitment and gives JSX early delivery positions. The distinction matters in an aircraft program scheduled to enter service in 2031: the agreement gives Heart a customer partner for design and operational planning while leaving certification and production execution ahead.