FAA Accepts Universal Hydrogen’s STC Bid for ATR 72 Conversion

The agency also issued guidance to establish certification criteria for the aircraft conversion to electric motors powered by hydrogen fuel cells.

Universal Hydrogen's modified ATR 72 in its hangar in Toulouse, France

Universal Hydrogen is using this modified ATR 72-500 hydrogen fuel demonstrator to develop its hydrogen retrofit kit. (Courtesy: Universal Hydrogen)

The move toward alternative fuel sources for airliners has taken a step forward as the FAA accepted Universal Hydrogen's application for a supplemental type certificate (STC) for the conversion of ATR 72 regional airliners to electric motors powered by hydrogen fuel cells.

The FAA on Thursday issued the G-1 Issue Paper that establishes certification criteria, including airworthiness and environmental standards required by the FAA to ultimately certify the Universal Hydrogen design for ATR 72 conversion to hydrogen power.

California-based Universal Hydrogen will continue working with the FAA to finalize the full certification requirements.

Hydrogen Logistics

In addition, the company is building a hydrogen logistics network. According to Universal Hydrogen, its modular hydrogen capsules can be transported over the existing freight network from production directly to the airplane anywhere in the world.

Universal Hydrogen is also working to certify a powertrain conversion kit to retrofit existing regional aircraft to fly on hydrogen.

In July 2022, Universal Hydrogen unveiled its test demonstrator aircraft, a modified ATR 72-500 at its facility in Toulouse, France. The airplane’s powertrain was converted from a conventional turboprop configuration to electric motors powered by hydrogen fuel cells. 

The conversion kits for ATR 72s include proprietary, liquid hydrogen modular capsules intended to make green hydrogen fuel transport and loading effective and efficient.  

Several air carriers are taking notice of the new technology. In 2022, Universal Hydrogen secured a deal with Connect Airlines for a firm order to convert 75 ATR 72-600s to hydrogen powertrains. The agreement includes an option to convert 25 additional aircraft. Deliveries are expected to begin in 2025.

Meg Godlewski has been an aviation journalist for more than 24 years and a CFI for more than 20 years. If she is not flying or teaching aviation, she is writing about it. Meg is a founding member of the Pilot Proficiency Center at EAA AirVenture and excels at the application of simulation technology to flatten the learning curve. Follow Meg on Twitter @2Lewski.

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