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PRO
Turbine Engines

The PRO series turbine includes the ProECU turbine controller which has significantly improved turbine safety through improved software and standardization of how the ProECU is configured and connected to your receiver. All turbine operation is now controlled from a single switched channel on your transmitter focusing regular operation and emergency shutdown from the same switch.

  Jakadofsky PRO Edition Turboshaft Turbine  $5,235.00 

  Jakadofsky PRO5000 Edition Turboshaft Turbine  $5,978.00 

General Turbine Operation

Modelers transitioning to turbine power need to familiarize themselves with the absent-coupling between the engine and the helicopter's collective pitch. In nearly all non-turbine model helicopters, the coupling between throttle and pitch is critical and needs to be carefully setup. Turbines are very different.

Classical Matching of Pitch & Throttle Curves

Every modeler that starts out in a glow powered model helicopter initially struggles to setup pitch and throttle curves on their transmitter. The difficulty comes from understanding how the two-stroke engine develops speed and torque as it accelerates. As modelers become more experienced with their engine and transmitter they are able to achieve a very predictable flight response. Those modelers that become proficient may also invest in a throttle governor which connects physically to the engine and will regulate its speed to maintain a fixed rotor-head RPM through all flying maneuvers.

Normal Turbine Operation = Fixed Turbine RPM

In stark contrast, the turbine engine is started and automatically spooled up to an operating RPM with the helicopter's blade pitch in neutral. Once the operating RPM is achieved the turbine will signal the pilot using the auxillary LED and the pilot can lift the helicopter off the ground. Once in the air, the turbine speed remains very constant reacting only to the largest changes in pitch. The turbine's fundamental operation guarantees a constant rotor-head speed which can be fine tuned in the ProECU.

ProECU Setup: Receiver Connections for Jakadofsky PRO Edition Turbines

Modelers configuring their first Jakadofsky turbine engine who have previously flown electric, glow or gasoline powered helicopters need to learn that the turbine control must be on a dedicated switched channel on the transmitter. The best choice is a 3 position switch, but a dial or slider will be equally suitable. As demand for Jakadofsky turbines is steadily growing, we know that standardizing turbine control will lead to safer operation where everyone benefits. This is less familiar initially, however model turbines are complicated already and this design change in the ProECU helps to simplify turbine operation and makes setup simpler. Table 1 details the recommended receiver setup.

Depending on your transmitter, you may have a choice for the turbine control switch. It is no longer possible to use a two position (2P) switch here. The ProECU reads the three position (3P) switch as Off, Idle and Max operating speed. While we do not actively change the turbine RPM during flight in helicopters, occassionally the model is flown at a location that has a different altitude or humidity that affects the engine and its operational RPM can be adjusted. Many factors contribute to what that flying speed should be including fixed elements like the model weight and rotor blade type to variable elements like the air temperature and humidity which change day to day.

Turbine Autostart Procedure - Propane Start Fuel

The turbine switch is the only way to start or stop your Jakadofsky turbine engine and can be used at any operating speed. The engine will automatically follow the next procedure during shutdown to ensure the engine cools off to a temperature below 80 degrees to avoid damaging internal components.

Turbine Autostop Procedure

ProECU Expanded Turbine Statistics

At the end of each flight reconnect the data console to the ProECU and record the flight's statistics in a notebook for your turbine. This is how you can track your engine's performance and detect variations in the data which eventually lead to operating problems. Scroll to the INFO menu and at a minimum record the EGT-PEAK and FUELPUMP-PEAK values. If the EGT-PEAK reaches or exceeds 700 degrees celcius, you should look for ways to reduce the loading of the turbine. This is an indicator that the turbine is getting too hot. If the turbine engine reaches 800 degrees, it will automatically shutdown to avoid internal engine damage. The FUELPUMP-PEAK value should remain below 4.2 volts, seeing higher voltage is an indication there is a problem with the fuel supply to the engine. Check the fuel clunks, fittings, tubing and fuel pump for dirt or loose connections. In some situations, the fuel pump voltages appear normal, but fuel flow problems result in a decrease in turbine RPM with a high EGT reading during flight.

In addition to the these two key data points, the following information is now available after every flight in INFO and STATISTICS of the ProECU. EGT-AVERAGE, RPM-PEAK, RUNS-TOTAL, RUNS-ABORT, HOUR-METER, LAST-OFF

ProECU Kerosene Start Factory Option - PRO Edition turbines only.

The ProECU accomplished another design request to remove the requirement for gaseous Butane/Propane fuel to start the turbine. In our opinion, both methods have been proven equally reliable and the choice comes down to the modeler and the particular fuselage or sport model mechanics. The key issue, is the Kerosene igniter is taller and will not fit inside scale models with a tight fitting engine compartment like the Huey. The turbine also requires the use of the 11.1V 3s LiPoly or 12V Nicad starting battery, as addition RPM is needed to spool the turbine during engine start and shutdown. A fully charged battery is good for 2 flights before recharging. Due to design differences relating directly to the power output between the SMT Edition and the PRO Edition turbines, the Kerosene start option will only function on the PRO Series turbines.

Turbine Autostart Procedure - Kerosene Start Fuel

Modelers switching to the ProECU from the older AECU:

The ProECU combines the turbine safety switch and the turbine RPM switch into a single switch which now only consumes one channel on your transmitter. The ProECU now requires a proportional switched channel that has ATV settings for the travel range. Optimally this is a 3 position switch, but a dial or slider is equally suitable. Factors contributing to this change originate in the absent-coupling between the turbine RPM and the collective pitch on the helicopter along with improving the safe operation of our turbines. Customer feedback initiated this design change where customers felt that one switch would be easier and less complex. Forcing pilots to use a switched channel also helps to standardize how Jakadofsky turbines are setup on all transmitters making it easier to troubleshoot and improves safety when flying or in an emergency situation.

Fundamentally in our opinion, using the throttle channel introduced too many liabilities for turbine control. For new turbine modelers, it was fairly simple to apply the traditional throttle channel configuration for your turbine's speed. What was not so simple to understand was just how easy it was to accidentally switch your turbine to idle in flight, which means an immediate auto-rotation to land your model safely because of time required to spool the turbine down and back to operating speed. This reinforced the design change to prohibit using the throttle channel for turbine control.

Not all modelers will agree that this is a better way. We firmly believe that this will result in safer turbine operation, avoids the potential of accidentally changing to idle in flight, consolidates all turbine control to a single switch and standardizes the turbine setup on all transmitters.