Wren Turbines 44 TurboProp Installation And Operating Manual Download Page 16 | Manualshive

Page: 16 / 36

background image

Wren 44 TurboProp Users Manual. Copyright Wren Turbines Ltd February 2008 Page 16

Performance

We have tested the turboprop unit in a variety of situations and loads. The main indicator of the
performance of the unit from the users point of view, is the rpm that can be achieved with a given
propeller load. Larger propellers and/or more blades produce higher torque figures but not always
the highest thrust figures.

We have listed the outputs for a range of propellers and the thrust produced for each combination
together with the calculated torque and shaft power figures. From these it should be possible for
the reader to gauge the ideal propeller combination for their aircraft.

The figures are reproduced in order of highest thrust first and are with gas generator at maximum
speed - 195,000rpm.

Propeller

Size

RPM

Static Thrust Torque

KW

HP

2-Bladed:

MENZ-S

610 x 200 (24” x 8”)

7110

167N

6.82Nm

5.08

6.81

MENZ-S

610 x 305 (24” x 12”)

5900

160N

7.06Nm

4.36

5.84

APC-N

430 x 305 (17” x 12”)

8900

95N

4.49Nm

4.18

5.60

3-Bladed:

Mejzlik

560 x 305 (22” x 12”)

6300

150N

8.52Nm

5.62

7.53

Mejzlik

510 x 305 (20” x 12”)

7020

135N

7.22Nm

5.31

7.12

MENZ-S

460 x 305 (18” x 12”)

7540

128N

5.47Nm

4.32

5.79

Note the high rpms achieved with the smaller propellers. It is most important that propellers
smaller than listed are not used or if they are the maximum rpm should be reduced on the engine,
to prevent the possibility of overstressing (the propeller). In all cases, follow the propeller
manufacturers recommendations for preparation and use.

NOTE

The maximum speed of the unit with

any

propeller should not exceed 9,000rpm on the ground.

«
...
14
15
16
17
18
...
»

Summary of Contents for 44 TurboProp

Page 1: ...TU U UR R RB B BO O OP P PR R RO O OP P P I I IN N NS S ST T TA A AL L LL L LA A AT T TI I IO O ON N N A A AN N ND D D O O OP P PE E ER R RA A AT T TI I IN N NG G G M M MA A AN N NU U UA A AL L L Copyright Wren Turbines Ltd September 2008 ...

Page 2: ...e system 9 Detail description of the turboprop unit and ancilliaries 13 Safety issues do s and don ts 14 Warranty service and repair 15 Performance 16 Propeller selection and balancing 17 Fuel consumption duration 20 Installation Do s and Don ts 22 Wiring and Plumbing Schematic 35 Installing the system components 23 Connecting the system components 27 Setting up the ECU 28 ECU Failsafe function 29...

Page 3: ...ere are a large number of airframes already available in the 2m 6 size that are attractive for conversion to turbo prop for the reasons outlined above and are suited for the average club flier The low installed weight around 2kg compares well with equivelent 2 cycle engines and helps to keep the wing loading sensible Noise is becoming a major concern and the 44 turbo prop enjoys a remarkably low n...

Page 4: ...uel solenoid 8 Propane solenoid with attached adjustable flow control valve 9 Propane tank and one way valve 10 Brass two part quick release propane connector Lay out the engine and its support equipment on a clean surface and identify all the components Weights and Measures Weights Power unit complete with cables 1710g 3 3 4 lbs Fuel pump 88g 3oz Valves Propane and Fuel 65g 2 1 4oz ECU Engine Con...

Page 5: ...mm 1 1 2 Max propeller thickness 30mm 1 3 16 Prop driver diameter 40mm 1 1 2 Prop nut size 12mm A F Glowplug JP PowerPlug type F A couple of templates for making the cutout for the engine mounting are included at the rear of the manual to full scale Simply cut out stick to the front of the firewall and cut through The template looks like this reduced version for show only GlowPlug Viewed from Prop...

Page 6: ...peed of the exhaust gas with the result than only a small residual thrust remains from the exhaust outlets What happens if I stall the propeller When operating from long grass or in a nose over situation that causes the propeller to stall the gas generator will continue to function normally with little ill effects On releasing the propeller from its stalled form it will spin back up to it s normal...

Page 7: ...ignites easily With no exposed high temperature components the risk of accidental combustion is greatly reduced As starting is undertaken with the operator and observers behind the propeller there is no possiblility of a sudden power surge allowing the aircraft and propeller to run forward to the operator such as can happen with I C engines with disastrous consequences for fingers and limbs The 2n...

Page 8: ...ted with a very small amount of fuel which at low rpms or throttling down can sometimes be seen as a small puff of smoke but this is normal The minimal oil percentage used in the fuel helps to minimize pollution from unburnt fuel although operation of the gas turbine does produce an very distinguishable smell which for many is the raison detre of this type of model flying What propellers do you re...

Page 9: ... stainless steel is bolted to the engine A purpose made 66mm power turbine not just taken from a thrust engine is cast in Inconel 713c and is fitted and running on a fully hardened and ground shaft in a pair of preloaded high speed ceramic angular contact bearings The shaft tunnel they run in is made from low expansion stainless steel These components define what is called the hot section Nothing ...

Page 10: ... which would normally be released to the interior of the aircraft Such heat release can cause heat damage to paint finishes cowl materials or make it difficult for the engine to get an adequate supply of essential cool air for the engine to run on We think the system is so good that some day all turbo props will look like this Ancillaries ECU Engine Control Unit Data display terminal RPM pickup mo...

Page 11: ...ey have very small gears to allow a wide range of control for the engine and must not be substituted for anything else Almost all other turbine fuel pumps are much too large and are therefore not suitable for this application and result in loss of control on this engine Be very careful whenever disconnecting or connecting it to ensure there are no small slices of pipe left at the inlet or outlet W...

Page 12: ...mer LiPo The capacity of this should be enough for at least three good flights but initially we recommend you charge after each flight to keep tabs on how much is being taken out by the flight LiPo s must be charged with a charger especially made for this type of cell and we recommend those equipped with a balancer or which charge through a balancer The battery has a balancing lead and it is best ...

Page 13: ... attain very high pressures that can cause pipes to blow off their connectors If it is deemed there is any possibility of this happening or if you experience this then switch to external plug in propane which reduces significantly the possibility of large propane release inside the aircraft SAFETY NOTES We make no apologies for positioning these notes early in the manual Please read the following ...

Page 14: ...age is wiped away immediately and clean any affected area with warm soapy water Wash hands and any affected part immediately after any contact Turbine oil can discolour or affect certain paint finishes Take precautions to prevent spillage Do not discard or allow any spillage to run into drains If removing the glow plug to test it keep fingers or bare skin away from possible burn from the glowing e...

Page 15: ...ue to use with unfiltered or contaminated fuel 8 Excludes damage to the unit in event of nose over or damage inflicted through prop strike 9 Crash damage to the engine and its ancillaries is not covered by the warranty 10 Warranty is not transferable Notes for the inquisitive Please do not attempt to disassemble this engine You will breach your warranty agreement and you will find it is a precisio...

Page 16: ...oduced in order of highest thrust first and are with gas generator at maximum speed 195 000rpm Propeller Size RPM Static Thrust Torque KW HP 2 Bladed MENZ S 610 x 200 24 x 8 7110 167N 6 82Nm 5 08 6 81 MENZ S 610 x 305 24 x 12 5900 160N 7 06Nm 4 36 5 84 APC N 430 x 305 17 x 12 8900 95N 4 49Nm 4 18 5 60 3 Bladed Mejzlik 560 x 305 22 x 12 6300 150N 8 52Nm 5 62 7 53 Mejzlik 510 x 305 20 x 12 7020 135N...

Page 17: ...nly a function of forward thrust against airframe drag A slippery airframe will result in far greater performance on even modest power levels whereas a large draggy airframe may fly slowly on even exceptional power Propeller Balancing It is imperative that propellers used on the turbo prop are balanced to a fine degree as the engine is produced utilising a high standard of balance on assembly A st...

Page 18: ...ull power again in the flight So fuel consumption figures must be used sensibly with an eye on how the engine is operated Fuel tank capacity The duty cycle anticipated of the aircraft will impact the choice of fuel tank capacity There is little point carrying around 3ltrs of fuel if the flying requires only 0 4 ltrs per flight Equally there is no point having a 0 5ltr tank for a fast aerobatic air...

Page 19: ... chasing the last dregs of fuel around at the bottom of the tank Flight Time Endurance How long a plane can fly on a given quantity of fuel is only of academic interest to most but it does give an idea where in the flight envelope is the most economical for those with an eye on the longest flight times Looking at the graph above a steady 100 000rpm on the engine equates to about 25N 5 1 2lbs thrus...

Page 20: ...et hot in use and may distort or discolour the finish if clearance is too small The glow plug and lubrication feed pipe must be positioned upwards see the cutout template at back of manual This is to ensure correct operation of the engine internal lubrication system during start up Inverted flight manoeuvres do not affect the lube system during normal running The fuel pump should be mounted at lea...

Page 21: ...es can run with 5 oil without harm if you want to keep just one mix for all your engines All pipe work used must be of the type supplied by Wren Turbines Fire Extinguisher Equip yourself with an appropriate fire fighting extinguisher whenever you are planning to run your engine The best extinguisher for our purposes is the Carbon Dioxide CO2 Use of dry powder foam or water based extinguishers will...

Page 22: ... Fuel to engine Fuel valve Fuel Pump Propane Tank optional Propane valve Propane to engine ECU RPM Pickup Temperature probe Glowplug Propane flow control Self sealing quick release connector Fuel tank Felt clunk pickup ECU battery LiPo 7 4v Receiver Receiver battery Wiring and Plumbing Schematic ...

Page 23: ...e main body and the two ears to clear the glowplug and lubrication fitting on the engine Offer up the engine unit to the hole and mark any tight spots Remove the engine and with a coarse file or modelling knife ease the opening Be careful not to injure the delicate lubrication fitting on the engine or damage the lubrication pipe the clear 3mm tube that connects to the gearbox whilst offering up an...

Page 24: ... Schematic on page 22 to confirm the order and location of all the ancilliaries the fitting of which follows Fuel Pump The fuel pump should be mounted close to the fuel tank to ensure only a short pipe run is needed Note the direction of flow on the pump Fit it with the black cap upwards if possible and with the pipes accessible just in case Fuel valve The fuel valve should be positioned fairly cl...

Page 25: ...the flow control components The filling side of the tank has a one way valve in it The outlet is plain and should be fitted with a suitable length of tube to the propane valve The tank only requires to be partially filled and needs to be liquid Use the self sealing quick release connector to connect the supply to the aircraft The main body part of the quick release is fitted with a short tube and ...

Page 26: ...ed to remake the joint simply cut the last bit off the Tygon and refit it onto a fresh end to keep it tight Fuel pump to fuel valve and engine The outlet of the fuel pump feeds the fuel valve directly note the direction arrow on the valve The outlet of the fuel valve feeds the engine fuel filter This pipe run can be some distance without causing any problems as it is a pressure line As before if y...

Page 27: ...trim down function Check your radio manual for this before you start As the display does not photograph well we have reproduced the display readings as a green box Turn on the transmitter and receiver The opening screen should show as below If the temp probe is not connected it will show as 0 C T ambient temp shown as 15 C but will be whatever you have locally at the time Note there are four butto...

Page 28: ...r engine and secondly you may change something which will adversely affect the starting and running of the engine Running Time Counter Using the 2nd left hand button v scroll through the menu s to the last menu The screen contains a timer which shows the total running time of the engine in minutes Tot the time in seconds of the last engine run Last the total number of starts cycles CY Use this scr...

Page 29: ... 2secs timer and engine control will return PCM IPD systems The user should program the failsafe function of the radio to send a signal lower than the normal stop signal ie if normal stop is 100 then program the failsafe to output 125 When the receiver enters into failsafe mode it will issue a signal to the FADEC of 125 that is outside the valid command window between STOP 100 and Full power 100 I...

Page 30: ...sitioned to discharge into the engine intake or the passage leading to the intake or alongside the engine towards the exhaust Do not point the extinguisher into the exhaust as this will surely carry hot gases back through the engine and into the aircraft and potentially cause more damage Never attempt to restart an engine which has been involved in a fire without a thorough and detailed examinatio...

Page 31: ...el should then be travelling along the feed pipe towards the engine and as soon as the fuel reaches the engine you will hear the engine note change The engine and propeller will start to accelerate and the engine rpm will rise past 30 000rpm as shown on the display you may hear the starter disengage and continue accelerating up to idle at around 55 000rpm If the engine slows below 30 000rpm at thi...

Page 32: ...ermocouple failure Contact Wren Temp reading shows lower or negative figure when gas lit Thermocouple plug inserted wrong way round Ensure connector matches the label on the ECU Rpm sensor plug inserted incorrectly Ensure connector matches the label on the ECU Rpm sensor lead broken chafed Contact Wren and remove source of chafing Rpm sensor malfunction Contact Wren No rpm indicated when engine is...

Page 33: ... ECU and shutdown if temp has run over 850 C due to long hot start low start battery or air in fuel line Cool off and restart Engine slows or is stopped during start Wild rpm reading Interference to rpm pickup by electromagnetic device sited too close find and move Check that Starter Glow wires are twisted Air in fuel line Check tank system for air leaks fuel flow problem Blocked FOD screen if fit...

Page 34: ...sensitive on the stick as only very small movements can result in large changes in output power Flyers might wish to program a throttle curve to reduce the response at the high end now that this function is standard on all computer radios The following data may be useful in deciding a starting point for a suitable curve A typical thrust table is shown below for a 610x200 24x8 2 bladed propeller En...

Page 35: ...as it can be the cause of flaming starts Once showing below about 98 C you can raise the trim and go for a start in the usual way Storage The unit does not need any special attention after running although some thoughts on storage can be considered Always remove or disconnect the LiPo at end of the flying session Charging must always be done with the LiPo disconnected but the ecu will draw a few m...

Page 36: ...e later GlowPlug Replacement It is presumed the operater is proficient at replacing the plug but a note on it s preparation may help The plug must be replaced by one of the same type the settings in the ECU on plug power rely on this If you replace it with one with aheavier element the ECU will surely blow it on the first go as it will supply too high a voltage for it If you go into the ECU settin...

Reviews:

No comments

Related manuals for 44 TurboProp

Brand: Mercedes-Benz Pages: 940

Brand: PCM Pages: 83

Brand: 3W Pages: 20

Calzoni MR Series

Brand: Parker Pages: 50

HP525 EFI Bravo Sterndrive Series

Brand: Mercury Racing Pages: 147

Brand: Selve Pages: 132

Brand: Vanguard Pages: 104

Brand: Clinton Pages: 7

RolloTube Comfort 2360 20 80

Brand: RADEMACHER Pages: 8

Brand: YS Pages: 2

Brand: YS Pages: 2

Brand: YS Pages: 2

Brand: Volvo Pages: 88

Brand: YS Pages: 2

Brand: Nanomotion Pages: 42

Brand: Agrimate Pages: 32

Brand: Chevrolet Pages: 17

Brand: Ingersoll-Rand Pages: 4

Brands by name

0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Popular brands

Load more brands