E-Props ...who has first hand experience with these

[Blueadventures]

18 hours ago, Kyle Communications said:

Mike..tie the aircraft down and set your pitch for 5500 wide open throttle on the ground. This is a good starting point. The ultimate aim is to get 5500rpm WOT in the air straight and level. Setting it like that on the ground will get you fairly close

 

Hi Mark  Pitch at 24.9, 25.0 & 25.1 (with 0.1 between the three) and 5400 WOT tied down on ground.  The rain came so no flight.  May have to wait a week at least now; bugger.  Not much difference between DUC and the E-prop but I'll do a new w&b anyway in the next week.  I'll keep you posted on results.  Hearing the Nynja factory testing in UK is seeing 113 kts (best to date is 105 kts) the performance looks like being better than expected.  

Edited April 19, 2022 by Blueadventures

[Blueadventures]

Fitted in an hour flight in the Nynja this morning. My findings were that I'm very happy with the E-Prop propeller. It was set with the three blades at 24.9, 25 and 25.1 degrees; being within the 0.3* I decided to leave as is and fly to evaluate. Ground static rpm was 5,400. First flight climb 1,400 f/m (better than DUC never much over 1,000 one up) Noticed had to put in right rudder (was perfect with DUC and the rudder input was more than acceptable) also during taxi to take off point noticed low rpm was a faster travel speed, also runway is bitumen sealed. 4,500 rpm 85 kts; 5,250 gave 108kts (quickest with DUC was 105 kts at 5,500 rpm). Landed and moved rudder bungee 6mm to port. Take off climb 5,250rpm and 1,250 ft/m OAT 24*C. Only slight need of right rudder (certainly acceptable) so will move rudder bungee another 2mm to port. Will before next flight re-pitch for 5,500rpm static. There is wild weather coming so will be a week or so before flight.

[Mike Gearon]

On 21/3/2021 at 10:25 AM, Kyle Communications said:

All CSU (I gather thats what your commenting on Bruce) are expensive. I personally dont think they are worth the cost for the performance for our type of aircraft.

 

Posted above is the std type ground adjustable prop.

 

I believe Eprop are finalizing testing on their range of props for the Jabiru engines now as well

 

 

I’ve just found this thread via Blueadventures and the E Prop. 

Didn’t realise you are the Australian agent. I was viewing the whole e prop install with some slight skepticism. Seemed too good to be true and I’d remembered the stolspeed prop comparison and mentioned that…..That was the extent of my knowledge until coming across this thread. 
 

Now I see what it’s all about. I fly two current aircraft and for some reason the Rotax gearbox clunk is more pronounced in the Nynja with Bolly. I actively hold the throttle back against stop  with just left mag then shut down to minimise this. MT CSU prop without researching it could be lighter, there is no noticeable clunk. So, I get the lighter aspect from just this point of view.

 

Then noise and vibration. Pipistrel is vastly quieter because of slippery frame. It’s like the difference of turning on noise cancelling. So, anything that can reduce the noise level is a huge bonus. 
 

Vibration is probably equal between both aircraft. Noticeable and of course reduced vibration equals more mechanically and possibly more people friendly/ reduced fatigue.

 

CSU. I see you mention that above. I’ve not read the whole thread to this point. Will continue but wish to mention my experience with CSU in Pipistrel and upcoming S21 build.

 

CSU in Pipistrel. I set it full fine for take off 5800rpm and pull the flaps and throttle back by say quarter quadrant 26 MAP and set 5400 rpm at around 100ft AGL. 1100-1200fpm climb out at 80kn. Cruise 130-135kn 5400 rpm 26 MAP. Reality is I could set it at  5400 on the ground just like the Nynja and never think about it again. I set it full fine for landing as POH but for a go around I’d be just as happy at the 5400rpm pitch and one less thing to think about climbing out and the go around indicates something went wrong snd you have a bit to think about deal with at that point.

 

This brings me to the S21. We’ve (my build partner and I) decided to go UL520 and probably the turbo 220hp. UL USA say the turbo fits. If it was a choice between CSU benefits for tuning climb out and cruise or turbo then the turbo wins every time. It’s doing a way better job of dealing with air density, altitude and cruise performance as well of course as extra grunt on the climb out. Cost and complexity differences between turbo and CSU. I’m sure that’s a whole topic on its own. At first glance I’d say the turbo is less complex than a CSU and similar or less cost.

 

I’m becoming an e prop fan. Pity they don’t make them for the higher hp aircraft! 

 

 

 

 

 

 

 

[Blueadventures]

Did another hour today; 2nd session and third flight with the E-Prop.  Pitched decreased to 24.5* from 25*.  Turbulent air so had to get above 3,500ft for smooth air.   Happy with results.  WOT s&l 5,450rpm 108Kts.   4,000rpm - 75kts, 4,200rpm - 80kts, 4,400rpm 85kts, 4,800rpm - 90kts, 5,100 - 100kts,   I'll look at 4,800 to 5,000rpm for cruise of 90 to 95kts.  Have a two hour trip end of month to Old Station so will start seeing the actual performance including fuel usage etc and do a few local trips before hand.

[Kyle Communications]

I will be in Rocky that weekend. Trouble is that its for a wedding not aircraft 😞

 

[jackc]

But the wedding won’t run all weekend Mark 🙂

[Kyle Communications]

Mate...the boss has "plans". She who must be obeyed commands it so..especially when they are close friends....Mind you Jack she did ask me where you lived. We are heading to the farm on Wed night after work then stay Thursday and drive to Rocky friday..wedding is saturday and the boss has hair appointment in the morning. We head back to the farm on Sunday and overnight to drive back here Monday. Belive me I would love to be going to Raglan...are you going?

 

[jackc]

Yes, working there on ground support crew for our flying club CDFG.  Going Friday lunchtime to camp there for weekend.

[Blueadventures]

For info; after adjusting the pitch I check and make final adjustment with my laser pointer pen fitted on my pitch adjuster.  The distance between the dots is means that pitch is within 0.09 (less than 0.1 and the manual asks for within maximum 0.3 degree so close enough for the second pitch adjustment trail.  All good now at 24.5 degrees so will fly this for a while.

 

Edited May 6, 2022 by Blueadventures

[IBob]

Blueadventures, did you also check blade tracking?

[Blueadventures]

Not checked the tracking as prop very flexible and tip end portion has little rake as the aggressive cupping and pitch is the inboard 1/3rd.  Very happy with the prop did a 1.4 hour flight yesterday (Thursday) and did some long runs s&l at various rpm settings.  Will be doing a 2.3 hour flight each way at end of month    will have an indication of performance after that.

[Mike Gearon]

Enjoying learning how your E Prop testing goes. 3kn is significant. 105 to 108 means efficiency gains for fuel economy even if you don’t need to get somewhere faster or of course when  dealing with rough air.
 

Rotax RPM also  to be an endless debate at the 5000 range and the 5400RPM. My local Tooradin and Tyabb mob are for the better part firmly in the 5000 26 map camp.

 

I was advised by Michael Coates the ex Pipistrel dealer to run the higher rpm because the rotax is labouring at 5k 26 map. It certainly sounds that way as you adjust the CSU back if all the way from 5800 take off to 5000k after climb out.

 

Also. This guy has huge experience.….

 

https://www.rotax-owner.com/en/912-914-technical-questions/5405-cruise-rpm-in-912-motor

 

[IBob]

10 hours ago, Blueadventures said:

Not checked the tracking as prop very flexible and tip end portion has little rake as the aggressive cupping and pitch is the inboard 1/3rd.  Very happy with the prop did a 1.4 hour flight yesterday (Thursday) and did some long runs s&l at various rpm settings.  Will be doing a 2.3 hour flight each way at end of month    will have an indication of performance after that.

How far in from the tip are you gauging the pitch?

 

In my view, if setting pitch with a laser, you also need to be checking the (static) blade tracking, since any difference in blade tracking will (also) shift the laser dot on the floor.

[Blueadventures]

5 hours ago, IBob said:

How far in from the tip are you gauging the pitch?

 

In my view, if setting pitch with a laser, you also need to be checking the (static) blade tracking, since any difference in blade tracking will (also) shift the laser dot on the floor.

Position is as per manufactures spec (page19 if you have a copy) the edge where the titanium leading edge meets the carbon leading edge.  Initial pitch set with the supplied guage and then I follow up with the laser pointer.  I'm in early days with this prop and have been involved in pitch setting of some E-props in Tractor and pusher configuration with 3 and 4 blade modes.  Later on I will adjust for 5500 - 5600 and higher; but for the next month or so will settle at this and record performance over long legs at set rpms. 

[Blueadventures]

5 hours ago, Mike Gearon said:

Enjoying learning how your E Prop testing goes. 3kn is significant. 105 to 108 means efficiency gains for fuel economy even if you don’t need to get somewhere faster or of course when  dealing with rough air.
 

Rotax RPM also  to be an endless debate at the 5000 range and the 5400RPM. My local Tooradin and Tyabb mob are for the better part firmly in the 5000 26 map camp.

 

I was advised by Michael Coates the ex Pipistrel dealer to run the higher rpm because the rotax is labouring at 5k 26 map. It certainly sounds that way as you adjust the CSU back if all the way from 5800 take off to 5000k after climb out.

 

Also. This guy has huge experience.….

 

https://www.rotax-owner.com/en/912-914-technical-questions/5405-cruise-rpm-in-912-motor

 

Thanks Mike;  I have been a follower and like Roger Lees comments and info.   My KISS for any 5,200 if set is to after takeoff drop 100 rpm to 5,100rpm.  Was doing this in 2012 on with my UL 80hp in a Skyfox.  I am an advicate for the 5500 to 5600 seting  to date and for now have 5450 rpm WOT s&l and I'll record how this goes then make adjustments.  Want to do some flying trips and looks like not many good days between now and end of month Old Station trip.

[IBob]

1 hour ago, Blueadventures said:

Position is as per manufactures spec (page19 if you have a copy) the edge where the titanium leading edge meets the carbon leading edge.  Initial pitch set with the supplied guage and then I follow up with the laser pointer.  I'm in early days with this prop and have been involved in pitch setting of some E-props in Tractor and pusher configuration with 3 and 4 blade modes.  Later on I will adjust for 5500 - 5600 and higher; but for the next month or so will settle at this and record performance over long legs at set rpms. 

I don't have the prop...or the manufacturer's spec.

Presumably this is further in from the tip than the traditional 1/3 radius in?

[Blueadventures]

11 minutes ago, IBob said:

I don't have the prop...or the manufacturer's spec.

Presumably this is further in from the tip than the traditional 1/3 radius in?

I'll measurenext time at the hangar and let you know.  also on the prop image on the floor you get an idea of distance ratio,  Going out now so I'll look later.

[RFguy]

I'd suggest 5100-5250 cruise from what I have read (lots) .

Take a look in the rotax OM-912_series_ED4 manual.

beware that some charts are for variable pitch prop.

Max torque is generated at about 5150  RPM @MAP = ~ 27 - 27.5

manual says for variable pitch prop = 75% output = 5000 RPM and  26" MAP 

 

there are some rotax bulletins warning about setting the cruise speed pitch (that you will spend the majority of your time at ) at < 5000 RPM. "reduced gearbox life, excessive oil consumption" etc

 

* but that depends on the load on the prop *.

If the pitch is over or under the maximum efficiency for the airspeed that will change the prop loading. 

 

I *guess* load on the prop is higher at airspeeds below the maximum efficiency airspeed (for that pitch). Does to a point where there is a stall on the prop blade very slow (I guess )

and *I guess* the loading on the engine falls to zero at infinite airspeed (IE airspeed higher than the maximum efficiency airspeed )  (putting drag aside)

 

Edited May 7, 2022 by RFguy

[Kyle Communications]

Lots of yanks cruise at 5400 and 5500...I never push mine that hard except on takeoff. I usually cruise mostly at 5000 but sometime 5200

 

[RFguy]

mmm

The performance boaties I read, for best sustained cruise,  prop for RPM = peak torque  up to  RPM= peaktorque + 5%

which is inline with the 5150-5350 region for  the 912ULS case.

[Garfly]

 

 

 

[Kyle Communications]

Not for Jabiru though

Eprop tell me the new Jab prop will be released towards the end of this year once they get all the CNC machinery made for the new factory they have just built

 

[meglin]

They are stubborn guys. If they said it, then they will do it. In the meantime, you can borrow from us :).

[Garfly]

E-Props demonstrate the Glorieuse CS on their Skyranger test machine. 

 

 

[Kyle Communications]

A  new development by Eprop..this is for the RV-12 and a rotax but I think maybe available at a later date for all the range when fitted to a Rotax. I have asked if they will be available and will get a unit for testing

 

https://blogen.e-props.fr/archives/10903/e-props-for-vans-rv-12-special-pitot-system/