Jet Central Rabbit User manual

OPERATION AND
MAINTENANCE MANUAL

January, 2009 1
INTRODUCTION
JET CENTRAL produces the most advanced micro turbines available today: smaller,
more powerful, faster acceleration, less fuel burn, lower temperatures, higher quality,
less maintenance and the best price. JET CENTRAL, an ISO 9000 Company is a full
production engine manufacturer, producing high quality parts to be assembled into
the newest line of micro turbines....
We are committed to our turbines in a way never seen before. You won’t find a more
knowledgeable company in micro turbines to turn than to JET CENTRAL.

January, 2009 2
TABLE OF CONTENTS
1. SAFETY INFORMATION……………………………………………………………………………….....………3
1.1 SAFETY RULES……………………………………………………………………………….……………….5
2. TURBINE SYSTEM COMPONENTS DESCRIPTION…………………………………….……………………6
2.1 PARTS LIST……………………………………….……………………………………………………………6
2.2 TURBINE……………………………………………………………………………………………….…….….7
2.3 I.C.S………………………………………………………………………………………………………………8
2.4 FUEL / OIL SYSTEM…………………………………………………………………………………………...9
2.5 STARTING GAS SYSTEM……………………………………………………………………………………..9
2.6 KEROSTART SYSTEM…………………………………………………………………………………………9
2.7 HAND DATA TERMINAL (HDT)……………………………………………………………………………….9
3. TURBINE SYSTEM INSTALLATION INSTRUCTIONS…………………………………………………….…10
3.1 I.C.S…………………………………………………………………………………………………………….10
3.2 PUMP/STARTER BATTERY…………………………………………………………………………………11
3.3 RADIO RECEIVER……………………………………………………………………………………………11
3.4 THERMOCOUPLE………………………………………………………………………………………..…..11
3.5 FUEL PUMP LINE OUT………………………………………………………………………………………12
3.6 RPM SENSOR…………………………………………………………………………………………..…….12
4. PROGRAMMING THE I.C.S…………………………………………………………………………………...…17
4.1 FIRST SCREEN………………………………………………………………………………………………..17
4.2 MAIN SCREEN…………………………………………………………………………………………………17
4.3 SECONDARY SCREEN………………………………………………………………………………………18
4.4 MENU SCREEN…………………………………………………………………………………………..……18
4.5 START SUBMENU FOR GAS START……………………………………………………………...……….19
4.6 START SUBMENU FOR KEROSTART…………………………………………………………….……….20
4.7 INFO SUBMENU……………………………………………………………………………………………….21
4.8 RADIO SUBMENU……………………………………………………………………………………….…….23
4.9 RUN SUBMENU………………………………………………………………………………………..………26
4.10 LAST RUN SHUTDOWN REASON………………………………………………………………...………27
5. RADIO LINK FAILSAFE…………………………………………………………………………………………..28
6. STARTING THE ENGINE…………………………………………………………………………………..…….29
7. PROPER RANGE CHECKING……………………………………………………………………………..…….35
8. FUEL AND FUEL SYSTEM CARE……………………………………………………………………...……….36
9. MULTIENGINE INSTALLATION…………………………………………………………………………………37
10. MAINTENANCE…………………………………………………………………………………………...……….38
11. TROUBLESHOOTING…………………………………………………………………………………………….39
12. IMPORTANT UPDATES…………………………………………………………………………………………..41
13. ECU LEARNING PROCEDURE…………………………………………………………………………….……42
14. WORLDWIDE SERVICE………………………………………………………………………………………….43
15. LIFETIME TURBINE WARRANTY………………………………………………………………………………44

January, 2009 3
1 Safety Information
The JET CENTRAL TURBINE ENGINES are in its own right a single stage centrifugal flow
gas turbine engine, configured to operate as a TURBOJET ENGINE for use mainly, but not
exclusively, in remotely piloted fixed wing aircraft. Such aircraft and their control systems
must be appropriately designed and constructed to be compatible with the performance of the
TURBOJET ENGINE.
NOTE: The airworthiness, structural design, integrity of the aircraft and its control systems
are the entire responsibility of the owner/builder/operator. JET CENTRAL and its agents
cannot accept responsibility for any failure, structural or otherwise, of the aircraft or its control
systems. JET CENTRAL and its agents cannot accept responsibility for any inappropriate or
unauthorized use of the JET CENTRAL ENGINE.
The JET CENTRAL gas turbine engine is a very safe, easy to operate unit. The JET
CENTRAL is a state of the art gas turbine engine and all components are manufactured
within the highest standards. If operated correctly it will provide years of reliable, trouble-free
service, with low maintenance.
It cannot however, be stressed highly enough, that the operating instructions be fully
understood before attempting to operate your engine. Any alterations to the engine
whatsoever, without the written consent of JET CENTRAL, will render any warranty
null and void and as a consequence the controlling body in your country may not grant
approval for use.
The JET CENTRAL gas turbines are high performance TURBOJET ENGINES that need
discipline, commitment to correct and safe operation. With other persons present while
operation, the TURBOJET ENGINE ALWAYS ENFORCE THE PROPER SAFE DISTANCES
FROM THE TURBINE!
The recommended minimum safe distances are:
In front of the turbine: 15 feet
Beside of the turbine: 25 feet
Behind the turbine: 25 feet
Fire extinguishers should be on hand at all times. JC recommends CO2variety. To avoid
hearing damage, always use hearing protection when near a running turbine engine. When
the turbine is running never place your hands closer than 6 inches into the area of the intake.
An EXTREME SUCTION, which can grasp a hand, fingers or other objects in a flash,
prevails in this area. Be aware of this danger always!

January, 2009 4
Prevent foreign materials from entering the intake when working the turbine. Before
operation, make sure there are no lose parts or debris near the turbine. Objects being sucked
in can cause severe damage.
Always exercise caution around the hot parts of the turbine, to avoid burns. The outer case at
the turbine stage and nozzle reaches 400 - 500ºC (750 - 950 ºF), while the exhaust gas may
exceed 600º C (1290 ºF).
Assure that the fuel is mixed with the correct amount of synthetic oil for the specific engine.
Use only synthetic turbine oils always.
Use common sense when operating model turbine jet aircraft. Never operate in or around
heavily populated areas, and in or around areas experiencing drought or dryness.

January, 2009 5
1.1 Safety Rules
Rule 1 Never run your engine indoors; always ensure you are in the open air.
Ensure non-associated persons are at least 9 meters (10 yards) away from
the engine when running. Always have a fully operational CO2fire
extinguisher available and ready for use when starting and running your
engine.
Rule 2 When bench running or engine starting in an airframe; never allow yourself
or another person to stand behind or in the rear quadrant of the engine.
Always ensure the exhaust of the engine is directed away from persons and
property as the heat of the engine exhaust can cause damage and injury.
Rule 3 Air will save the engine, in the event of a hot or failed start always isolate
the fuel to the engine, but always keep the start air running to the engine,
this will clear the engine of residual fuel and will keep the core of the engine
cool. If you are using the Electric starter, once again isolate the fuel supply
to the engine and keep the starter running. Do not be afraid to use your fire
extinguisher, a CO2extinguisher will not harm the engine in any way. A
hand held blower is another good safety item to have on hand during the
start up and shut down of the motor.
Rule 4 Never attempt to start a flooded or wet engine, this will result in a hot or wet
start and you will have flames. To dry out or clear the engine, stand it tail
pipe down and either run the starter motor or blow air through the engine
until all residual fuel has been blown out of it.
Rule 5 Always start the engine with the nose of the plane pointed into the wind and
shut down with the nose pointed into the wind also.
Rule 6 In the event of a hot start, or sever engine fire, close the throttle and the trim
lever to the fully back position and turn off the fuel isolation valve, this will
allow the engine to clear itself, be ready to use your fire extinguisher. A CO2
type extinguisher will not harm the engine in any way; if a dry powder
extinguisher is used and the powder is ingested into the engine then you
must return the engine to our service department.

January, 2009 6
2 Turbine System Components Description
2.1 Parts List
Before starting installation of the engine please check the contents against the parts list. If
any part is missing or damaged, contact JET CENTRAL or their agent in your country for
correction. DO NOT substitute missing or damaged parts as this will void your warranty and
your country’s controlling body’s approval for use.
1 - Turbine Engine
1 - I.C.S. Unit
1 - Clear Fuel Line 4mm.
1 - Clear Kerosen Line 3 mm.
1 - Battery Li-Manganese
1 - Hand Data Terminal (HDT)
1 - Plug (4mm.)
1 - Manual
Box #1 with:
1 - Fuel Pump
1 - Fuel Valve
1 - Kerosen Valve
1 - Nylon Strap
1 - Fuel Pump Mount
Box #2 with:
1 - Festo “T” Connector (4mm.)
1 - On/Off Festo Valve (4mm.)
1 - Straight Festo Connector (4mm.)
1 - Straight Festo Connector (3mm.)
1 - One Way Festo Connector (4mm.)
1 - Fuel Filter
1 - RPM Extension
1 - Temp. Extension
1 - Power Extension

January, 2009 7
2.2 Turbine
It is a single shaft turbojet with an annular combustor. A single stage axial flow turbine drives
a single stage centrifugal compressor. The shaft is supported by 2 fuel/oil lubricated pre-
loaded angular contact bearings. The turbine speed is controlled by the amount of fuel
received from the fuel pump, which is controlled by the I.C.S.
Turbine Specifications
Bee II
Rabbit
Cheetah
Rhino
Mammoth
Thrust Class
7 Kg (15.5 Lbs)
@185,000 RPM
8.6 Kg (19 Lbs)
@152,000 RPM
14 Kg (31 Lbs)
@ 130,000 RPM
16.3 Kg (36 Lbs)
@ 117,000 RPM
21.5 Kg (48 Lbs)
@ 104,000 RPM
Full Throttle
Fuel
Consumption
0.24 Lt/min
(8.1 Oz/min)
0.31 Lt/min
(10.4 Oz/min)
0.47 Lt/min
(16 Oz/min)
0.52 Lt/min
(17.5 Oz/min)
0.70 Lt/min
(23 Oz/min)
R.P.M. range
55,000-185,000
40,000-152,000
35,000-130,000
30,000-117,000
28,000-104,000
E.G.T.
500°C - 700°C
(932 -1292°F)
500°C - 700°C
(932 -1292°F)
500°C - 700°C
(932 -1292°F)
500°C - 700°C
(932 -1292°F)
500°C - 700°C
(932 -1292°F)
Weight
0.880 Kg
(1.94 Lbs)
with starter
1.0 Kg
(2.2 Lbs) with
starter
1.360 Kg
(3 Lbs)
with starter
1.700 Kg
(3.75 Lbs)
with starter
2.240 Kg
(4.9 Lbs)
With starter
Diameter
82 mm
(3.228 inches)
91 mm
(3.582 inches)
102 mm
(4 inches)
111 mm
(4.37 inches)
124 mm
(4.881 inches)
Length
232 mm
(9.13 inches)
245 mm
(9.645 inches)
250 mm
(9.842 inches)
300 mm
(11.8 inches)
349 mm
(13.74 inches)

January, 2009 8
2.3 I.C.S.
The I.C.S. (intelligent Control System) is a total system for the control of a model gas turbine
engine. Its main function is to control and regulate the fuel pump, providing the turbine engine
with the necessary amount of fuel for safe and controlled operation.
The I.C.S. measures the exhaust gas temperature, the relative position of the throttle stick
and the rotor speed. It monitors all of the controls necessary to guarantee that the engine
stays between the user-defined parameters of operation, also providing fail-safe shutdown of
the engine when it has detected any important anomaly. In order to make this assessment,
the I.C.S. has a RPM sensor, a thermocouple input, a throttle servo input, power connections
for the fuel pump, starter, glow plug, fuel and gas valves, battery and a digital (RS232) serial
port to program and read the data in real-time to a PC.
The measurements made by the I.C.S. are:
Temperature of the exhaust gas
Pump battery voltage
Width of the throttle pulses from the radio
transmitter
Engine rotor RPM
Engine run time
External analog signal
All of these measurements can be read into and displayed on the Hand Data terminal (HDT)
that is connected to the I.C.S. by a RJ-45 connector, or into a personal computer through a
RS232 adapter. The configuration/setup parameters are stored in the I.C.S. by the HDT or
the PC.
Features:
RPM input: Magnetic sensor up to 250,000 R.P.M.
Temperature range up to 1000ºC using a "K" type thermocouple
PWM control of 8192 steps for pump
Build-in electronic brake for the starter motor to help the clutch to disengage
Blown glow-plug detector
Adjustable glow-plug power
Adjustable gas flow
Elapsed engine run timers
Status LED on the unit plus 2 more remote on option
RS232 interface to interface to a PC
Black box function. Record the engine measures each 0.5 sec up to 51 minutes
Used mAh counter
Bad RC pulses (glitches) counter

January, 2009 9
2.4 Fuel / Oil System
The Fuel/Oil is pre mixed together. Where the fuel line connects to the motor a T-fitting sends
some of the Fuel/Oil to the bearings and the rest is sent to the fuel nozzles in the combustion
chamber. It is important to filter the fuel and use proper types of fuel in the turbine Engine.
Without proper filtering one or more of the injector needles could become clogged, thus
affecting the proper running of the engine. Only synthetic turbine engine oil is to be used and
MIXED TO THE PROPER AMOUNT of 2.5% or 16 US ounces per 5 US gallons fuel.
2.5 Starting Gas System
When you choose “AUTO – GAS” option in the Start Menu.
In the initial start sequence, the motor uses propane or a propane/butane mixture. This
system uses an onboard gas tank and a solenoid valve to deliver the gas to the combustion
chamber, the glow plug is powered momentary to cause ignition. When certain parameters
are meet the fuel solenoid valve is opened by the I.C.S. and then fuel is used to bring the
engine to the proper idle RPM during the remaining ramps. The gas valve is automatically
closed when a certain RPM is reached during the fuel ramp.
2.6 Kerostart System
The main difference between gas and kerosene is that in the case of a failed ignition, the gas
dissipates quickly on the air and don't keep inside the engine. Kerosene is liquid and, if
unburned, will pool inside the engine and stay there forever. The engine can hold a big
quantity of kerosene inside. This kerosene will be ignited on next successful start up and will
be pushed to the exhaust as soon as the airflow inside the engine is sufficient, and will be
ignited in the exhaust, causing a hot start (in extreme cases a big fireball) that will not hurt the
engine, but can destroy the model.
2.7 Hand data Terminal (HDT)
The Hand Data Terminal is simple and easy to operate. The HDT is used to read the different
information and to program certain parameters in the I.C.S., this is a link between the user
and the I.C.S. Make sure to take the necessary time and learn the operation, as this is the
only exact way the operator can monitor and check that the turbine is running properly. The
unit is small and compact, but always remove it before flying.
Note: If you leave it installed, remember it uses power from your RX battery.
HDT

January, 2009 10
3 Turbine System Installation Instructions
3.1I.C.S.
Connections:
Throttle input to the receiver: JR type servo cable (Throttle RX)
Kerosen valve: JR type connector receptacle (Gas Valve)
Fuel valve: JR type connector receptacle. The central cable is positive and the two of
the sides negative (Fuel Valve)
RPM sensor: JR type connector receptacle (RPM Sensor)
Thermocouple: JR type connector receptacle (ThermoC)
Multiplex connector 1
Battery input: Red/black cable
Fuel pump: Red/Green cable
Multiplex connector 2
Glow plug: Red/Black cable
Starter: Red/Blue cable
Note: In all power cables the black is the common and negative. This means that all the black
cables are connected internally together and to the negative of the pump/starter battery.
Connect the cables in their places. Note that some of the JR type connectors used can be
connected in wrong place or inverted. Use the colored labels on the I.C.S. body to connect all
the connectors in their place. The configurations of the pins have manufacture to avoid
damage produced to the electronics in the case of a bad connection.
Please note that:
If the thermocouple connector is connected inverted, the temperature will decrease
when heated, and the I.C.S. will fail to recognize the gas ignition.
If the RPM sensor is connected inverted, no RPM will be read.
Use the recommended (supplied) starter motor battery or one of the same voltage. If
you decide to use a battery with different voltage, the turbine ECU has to be
readjusted at the factory.

January, 2009 11
I.C.S. Main Unit
Because the I.C.S. is an electronic piece of equipment, the installation in the model aircraft is
similar to that of the radio receiver. It has to be in an accessible location within the airframe,
with limited vibration and far from the heat of the engine. Also because the pump motor uses
DC power, that can produce sparks in the collector when operating, it is highly recommended
that the installation of all electrical equipment be done as far as possible from the R/C
receiver. Keep the power cables at the minimum possible length and avoid installing the
antenna near them.
3.2 Pump/Starter Battery
The I.C.S. needs for its operation two different power supplies. The first is taken from the
radio receiver through the throttle servo connection and the second is the battery that
supplies the pump. Reversing the polarity of the battery causes the destruction of the
semiconductors of the I.C.S.
The I.C.S. can work with pump battery voltages between 1.2V and 15V in manual start mode,
and from 4.8V to 15V in auto start mode. The selection of the number of battery elements is
define considering the real needs of the ancillary equipment like starter motor, solenoids
valves and pump motor. Use only the supplied battery or a same voltage substitute.
This battery does not need an on/off switch in the airframe since the I.C.S. has an internal
electronic switch, which disconnects it when the power to the receiver is switched off.
3.3 Radio Receiver
The I.C.S. is connected to the radio receiver like a standard throttle servo, inserted in the
channel for the throttle, receiving the information of the throttle control pulses and the receiver
battery supply. The ECU can work with voltages from 4.8V to 9.9V from the receiver.
3.4 Thermocouple
The I.C.S. uses a thermocouple of type “K”, good up to 1100ºC. The provided standard
thermocouple consists of an Ø1.5 mm diameter Inconel wire, finished with a connector that
fits directly on the I.C.S. The recommended installation is by inserting the end of the
thermocouple so that it is 2 mm, 1/16 inch, within the flow of exhausts gases; and plugging
the lead into the I.C.S. at proper input. Take note that the wire coming from the thermo
coupler has a solid green wire and a green and white wire. The input of the I.C.S. is color-
coded; make sure to line up the correct colors when plugging in this lead.
Never bend or cut the probe or probe wires. If you need to extend the wire, use a servo
extension.

January, 2009 12
3.5 Fuel Pump Line out
Note: the arrow on the pump shows the direction of the fuel flow.
Connect necessary length of 4mm tube in the suction side of the pump from the fuel supply,
and the 4mm output line to the fuel solenoid valve. Place the manual on/off valve between the
solenoid valve and the Turbine CLEAR fuel input line. We recommend placing the MANUAL
valve where it can be closed easily. JC recommends to safety tie all barbed fittings with
20mm safety wire.
Suction / to fuel tank
fuel solenoid
3.6 RPM Sensor
Connect the JR line coming from the turbine to the RPM input on the I.C.S.

January, 2009 13

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January, 2009 17
4 Programming the I.C.S.
The HDT has a LCD with 16 characters x 2 rows and four buttons which allow you to move
through the various menus and to change the data settings in each menu page. The
presentation of data has been organized in screens. The first two, displays the engine status
readings in real time and the following screens allow you to modify the operating parameters.
All of the parameters can be modified while the engine is running, so it is easy to tune the
engine without having to start it again to test the new settings. Both left buttons allow you to
move through the different screens in an ascending mode (Menu Up) or descending mode
(Menu Down). Both right buttons allow you to change the data in increasing value (Up Data)
or decreasing value (Down Data).
Menu down Data up/Enter
Menu up Data down
4.1 First Screen
When you have connected de I.C.S. and you turn on
the RX, appears briefly the presentation screen with the
Serial Number of your engine.
4.2 Main Screen
In this screen you have the status of the engine,
temperature (Centigrades), RPM and the power
supplied to the fuel pump (PW). This goes from 0 to
999.

January, 2009 18
4.3 Secondary Screen
If you push the Menu Up button you get to the
secondary screen.
Here you have the pulses from your transmitter,
the % of the accelerator stick, the voltage of the
I.C.S. battery and the software version.
4.4 Menu Screen
By pushing again the Menu Up button you get to the menu screen.
Here you have four menus to choose from:
Start
Info
Radio
Run
To get into each menu, simply push the corresponding button.
Start –menu down ( )
Info –menu up ( )
Radio –data down ( - )
Run –data up ( + )
All the parameters in the submenus are factory preadjusted and they have a good starting
point to fine tunning your engine. Make small changes at a time.

January, 2009 19
4.5 Start Submenu for Gas Start.
At the “Start” submenu you first get to this screen
Pushing the menu up button you get to “Glow plug
power”
With the Data up and Data down buttons you can
change this value. The idea is to have the lowest
possible value, that can ignite your gas so your glow
plug can last longer.
The next screen is “Start gas adjust”
Here you can change a little amount of the gas that
goes to the turbine. Again, the goal here is to have
the lowest possible gas but enough to have a
reliable start all the time.
The last screen in the start submenu is the “Low
batt adjust”.
If the voltage of the battery drops bellow this value,
the start cycle will be interrupted and you will gat a
“Low batt” alarm.
If you upgrade the I.C.S. battery mAh, you will may
increase this value to become closer to the nominal
battery voltage.