A33HF

The A33HF Propulsion System has been specifically designed to operate on heavy fuel. The combustion and fuel injection systems are tailored to meet the demanding requirements of cold start and high-performance operation while maintaining a compact package size and low weight.

 
 
Cobra AERO’s A33HF heavy fuel capable engine system
 
(A) Heavy Fuel Capable
The A33HF employs a combustion system developed utilizing decades of small engine heavy fuel experience. It's unique combustion chamber coupled with unique control algorithms provides powerful and worry free operation.
(B) Precise
The A33HF features a cylinder manufactured via Direct Metal Laser Sintering (DMLS). This provides several benefits including extremely low part-to-part variability, geometries that cannot be achieved through casting, and improved material properties.
(C) Durable
The A33HF is based on the A33N core which has passed the [FAR33 durability profile][1]. This accelerated durability test exercises the engine through a torturous path including long periods of maximum power and large temperature and speed variations.

 
Cobra AERO’s A33HF heavy fuel engine system
 
(D) Robust
The A33HF features a fully shut off Servo controlled cooling duct which allows the engine to operate in a relatively narrow temperature range; providing more efficient operation, improved durability, and allowing lower engine speed during descents.
(E) Compatible
The A33HF’s mounting flanges and form factor fit easily within the package envelope of most current hobby-level engine installations.
(F) Discrete
The A33HF’s additively manufactured exhaust system provides an excellent combination of durability, power, and low noise output. It also cowls extremely well for low prop masking and improved aerodynamics.