The Future of Advanced Air Mobility

Happy Takeoff Fast-tracks Prism Hydrogen-Powered eVTOL For 2023 Service Entry

Happy Takeoff is building a sub-scale prototype of a planned hydrogen-powered eVTOL aircraft and intends to begin remote-controlled flight tests by March 2021. The Kansas-based startup is working with Oklahoma State University on the 150-pound model as it pursues an ambitious plan to bring a fixed-wing aircraft called Prism to market in 2023.

The company’s engineering team is now defining the design for the Prism based on fresh input it has gathered from prospective customers and also on the latest advances in hydrogen fuel propulsion systems. The aircraft is expected to feature significant differences from an earlier design being developed under the name CitiFlex, which it has now discontinued.

Prism will seat up to six passengers and have a maximum payload of around 1,200 pounds. CEO Danielle McLean told FutureFlight that her team aims to convince ride-hailing group Uber to include hydrogen-powered eVTOLs in its planned air taxi network. The company also envisages many other applications, including support for air ambulance, search and rescue, firefighting, medical logistics, disaster response, and various military operations.

McLean said that the Happy Takeoff team has opted to conduct an extensive consultation with prospective users and stakeholders, including state and city leaders, before finalizing the aircraft design. “We learned that a lot of states and cities don’t want landing locations on rooftops so we want to minimize the need to have multiple skyports by having longer range,” she explained.

Prism is expected to be able to fly intra-city distances such as the 380 miles from San Francisco to Los Angeles. According to Happy Takeoff, it will prove to be more practical and cost-effective to provide support infrastructure for hydrogen-powered aircraft than for electric models that it says will need frequent recharging.

McLean is a former advanced product development engineer with Spirit AeroSystems who has a bachelor's degree in mechanical engineering from Wichita State University. She founded Happy Takeoff with COO Rachel Locks, who is due to graduate as a medical doctor in 2021, and CTO Dominique McLean, who is a software engineer.

The program’s aircraft design lead is Darold Cummings, a former Boeing technical fellow whose ForzAero company has been supporting aircraft developers including Wright Electric and Airflow. According to Happy Takeoff senior advisor Javin Pierce, Cummings’s design pedigree, defense background, and extensive project management experience provide a firm foundation for the company’s Prism program. Pierce himself has a background in research and development in medical technology, human factors, robotics, ultralight aircraft, and aerodynamics with startup firms and larger corporations.

A key plank of Happy Takeoff’s fund-raising efforts is a plan to raise $5.2 million to launch a subsidiary company in Hungary that will give it a foothold in the European market, while also providing a more cost-effective environment for some of the engineering work. At the same time, the company has applied for funding through the U.S. Air Force’s Agility Prime program and is seeking debt and equity financing for an additional $5 million.

“Our plan to seek funding in Hungary and the U.S. simultaneously arose in part because Europe is embracing green hydrogen with a passion that just isn’t here [in the U.S.] yet,” Pierce told FutureFlight. “Hungary is a perfect place to cultivate our partner team to take on the integration and engineering of our green hydrogen-generation systems and avionics, etcetera, that are not directly in the scope of Darold’s work on the airframe and flight systems integration.”

Pierce also pointed to Hungary’s membership in the European Union and the associated access to taxpayer funds to advance sustainable aviation initiatives as a further advantage. Additionally, the country is a NATO member state that is in the process of modernizing its military infrastructure and technology.

As it pursues an aggressive schedule to build a full-scale prototype and begin flight testing, the company has yet to complete the design of Prism’s propulsion system. It has had preliminary discussions with hydrogen fuel cell developer HyPoint.

“Once we take Prism out of stealth mode, we will be ready to reveal many more cutting-edge technologies that the aircraft will feature,” McLean told FutureFlight. “With the exceptional scope of Darold Cummings’s aircraft design experience, I’m convinced this will be a market leader.”