Welcome to N2 Turbines Inc. Our company is proud to announce our new division specializing in the design, development and manufacturing of a light-weight micro turboprop engine, (MTE) for the experimental fixed- wing and rotorcraft markets. Our market research indicates that there is a strong demand for an MTE power-plant that can deliver between 100-130 Shaft Horse Power, (SHP), to accommodate the emerging new generation of light aircraft designs. As the "N₂ Turbines" name suggests, our goal from the beginning is to provide a Turboprop engine with a Free Turbine (Split-Shaft) design. This means that there is no connection between the gas producer (GP) and power turbine (PT) reduction drive.

We have selected an innovative design, that places the Gas Producer outlet 90 degrees to the axis of the Power Turbine. This unique Sidewinder ^TM configuration gives us a more efficient transfer of power between the GP (Gas Producer) and PT (Free Turbine). This approach gives us a ground operation mode that is easy to control, roughly (30-40% N₂ at ground idle) with a low fuel burn of 1.2 to 2.2 gals per hour as well as a wide-power-range of in-flight cruise throttle settings without the need for an expensive and complicated prop control system.

Our initial discussion with airframe manufactures indicates that approximately 30% of the builders and pilots would favor selecting an MTE if offered as a FWF option. Our task would be to develop with the airframe manufactures support, a Fire-Wall-Forward (FWF) package specifically for those Tractor, Pusher and Rotorcraft applications.

Why build a dedicated split shaft Turboprop?

In the past few years, we have seen a proliferation in the Experimental Aircraft kit market,  with airframe designs based on the availability of 80-100 Shaft Horsepower, (SHP) engines. In a majority of  instances, these new and old designs have worked somewhat well with the existing legacy type reciprocating engines.

Over these past few years, it has also become apparent to us through our own experiences and others, that aircraft in the pusher configuration have  a disparity between their tractor pulling counterparts. Primarily, the limiting factor with these types of engines is due to cooling issues inherent in the pusher configuration, installation weights, and/or available horsepower, 

Some of the characteristics of the engine are as follows:

Minimum 100 Shaft HP
Split Shaft - “Free Turbine” design
Ground idle of 40% Ngp
Maximum prop speed of 3300 rpm

ECU Controlled

In cruise flight mode, the ECU senses and monitors three key components:  Ngp, Npt and EGT.

Together these (3) three inputs allow for operation at 100% Npt with maximum efficiency setting of the prop for exceptional high altitude performance. The engine retains 60% of its horse power at altitude.

Terms Used:
Ngp denotes the Rotational Speed of the Gas Producer
Npt denotes Rotational Speed Power Turbine
EGT stands for Exhaust Gas Temperature