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Starwood Edition
Turboshaft Engine

The Starwood turbine includes the PRO ECU turbine controller which has significantly improved turbine safety through improved software and standardization of how the PRO ECU 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 Starwood Edition Turboshaft Engine (with CNC Nimonic wheel) $4,798.00      

                   

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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 PRO ECU.

PRO ECU Setup: Receiver Connections for JAKADOFSKY Starwood Edition Turbine

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 PRO ECU helps to simplify turbine operation and makes setup simpler. Table 1 details the recommended receiver setup.

ChannelFunctionUseage
1 or 4ThrottleUnused
 AileronNormal
 ElevatorNormal
 RudderNormal
5Gear SwitchNormal
6Collective PitchNormal
7Auxillary 2-3P SwitchGyro Remote Gain
8Auxillary 3P Switch/Dial/SliderTurbine Control
Table 1. Auxillary channel for turbine control.

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 PRO ECU 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

StepConsoleEventAuxillary LED
1. Beginstop  
2. Turbine Switch: OFF -> IDLErun solid on
3. Cycle Turbine Switch: IDLE -> MAX -> IDLE
 rel-system release for startupsolid on
 spinturbine rotor is spinningsolid on
 firepropane ignitionsolid on
 heatshort chamber heat upsolid on
 accefuel pump starts solid on
 idleturbine idlesolid on
4. Set Collective Pitch to neutral (0 degrees)
5. Set Turbine Switch: MAX
 0%++increasing turbine powersolid on
 100%achieved maximum powerturns off
6. Add collective pitch to take off.
Table 2. Turbine Autostart Procedure

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

StepConsoleEventAuxillary LED
1. Land Helicopter
2. Turbine Switch: MAX -> IDLE
 100%- -decreasing turbine powersolid on
 idleturbine at idlesolid on
3. Turbine Switch: OFFofffuel valve closingturns off
 offengine cycles during coolingoff
 coolengine below 80 degreesoff
4. Reconnect the data console to retrieve flight statistics.
Table 3. Turbine Autostop Procedure

PRO ECU Expanded Turbine Statistics

At the end of each flight reconnect the data console to the PRO ECU 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 PRO ECU. EGT-AVERAGE, RPM-PEAK, RUNS-TOTAL, RUNS-ABORT, HOUR-METER, LAST-OFF

Modelers switching to the PRO ECU from the older AECU:

The PRO ECU combines the turbine safety switch and the turbine RPM switch into a single switch which now only consumes one channel on your transmitter. The PRO ECU 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.