Oshkosh, WI — July 22, 2025 — Piper Aircraft, Inc. is excited to announce the new Piper Seminole DX—a diesel-powered PA-44 Seminole featuring DeltaHawk’s FAA-certified, DHK4A180 180-horsepower, heavy fuel, compression ignition engine. The Seminole DX was born from a successful collaboration between Piper and DeltaHawk announced in early 2024. Piper will begin taking position reservations at EAA AirVenture in Oshkosh, WI, July 21-27, 2025.
The liquid-cooled, 180HP turbo-charged DeltaHawk engine produces turbine performance at 40% better fuel efficiency versus reciprocating avgas engines, while also achieving a significant reduction in cost of ownership due to fewer moving parts. The engine is approved for JET A and JET A-1 fuels, with Sustainable Aviation Fuel (SAF) approval pending. Piper will use a Piper-owned STC to integrate DeltaHawk’s firewall-forward kits into the Seminole production line. The kit includes counter-rotating DeltaHawk engines and three-blade, full-feather propellers. Additionally, the aircraft will have an advanced cabin temperature control system utilizing the engines liquid cooling to ensure a comfortable flight experience in diverse conditions.
“The market has been heard, loud and clear regarding the need for a reliable, cost-effective, heavy fuel, multi-engine training platform,” said John Calcagno, President and CEO of Piper Aircraft, Inc. “The new Seminole DX fills that market void perfectly. Based on interest received since our MOU announcement last year, we anticipate global market demand for the Seminole DX to be between 25 to 40 aircraft per year over the next 10 years. The DeltaHawk team has been a pleasure to work with over the past 16 months as they epitomize quality and customer focus. Future collaborations are in process as well.”
A 20-year Long Term Supply Agreement (LTSA) designates DeltaHawk as the exclusive heavy fuel, piston engine supplier for the Piper Seminole. Certification flight testing begins in November 2025, with FAA certification expected in Q3 2026, followed by certifications from Transport Canada, EASA, and India’s DGCA. Deliveries of 2027 model year Seminole DX aircraft are anticipated to begin in late 2026 or early 2027.
“The installation of our certified DHK engine in the legendary Piper Seminole is a perfect match with our industry-unique features to provide the lowest cost of ownership and the simplest and safest multi-engine training platform ever,” said Christopher Ruud, Chief Executive Officer of DeltaHawk Engines. “Just as important, we see this new 20-year agreement not just in terms of engines, but also as a wonderful step by Piper, utilizing DeltaHawk’s powerful innovation, while creating environmental sustainability for general aviation worldwide.”
The Seminole DX offers significant performance enhancements* over the current PA-44 Seminole, including a 35% reduction in fuel burn, a 32% increase in single-engine climb rate, and a 70% higher single-engine absolute ceiling.
* Note: Performance metrics are preliminary and subject to final certification testing.
Piper and DeltaHawk are exploring further engine applications for both the PA-28 Archer and PA-46 M-Class platforms, strengthening their partnership for future innovations.
About Piper Aircraft
Piper Aircraft Inc., headquartered in Vero Beach, Fl., offers aviators throughout the world efficient and reliable single and twin-engine aircraft and is the first general aviation aircraft manufacturer in the world to certify Garmin® Emergency Autoland. The single-engine M-Class series – the M700 FURY, M500, and M350 – offers businesses and individuals elegant performance, value and a superior ownership experience. The Personal Class Archer LX and Archer DLX balance proven performance, efficiency, and simplicity in a piston-powered light aircraft. The Trainer Class Pilot 100i, Archer TX, Archer DX, and Seminole aircraft form the most complete, technically advanced line of pilot training aircraft in the world. Piper is a member of the General Aviation Manufacturers Association. To learn more about Piper Aircraft, visit the company’s website at www.piper.com.
About DeltaHawk Engines
Based in Racine, Wisconsin, DeltaHawk Engines is a privately held manufacturer of advanced-design FAA-certified jet-fueled piston engines for general aviation aircraft and hybrid power systems. DeltaHawk holds numerous patents for its clean-sheet engine designs, and its team of engineers, designers, manufacturing specialists, and certification experts is building an entirely new generation of revolutionary piston engines. For more information, please visit www.deltahawk.com.
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Piper Aircraft
For further information, contact:
Alba Walcott
Phone: +1 (772) 299-2835
Fax: +1 (772) 978-6585
Mail to: alba.walcott@piper.com
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