NEW propeller for CT

[Jacques]

19 hours ago, Runtoeat said:

Hi  Jacques.  Thanks for letting us know about the E-Prop.  Basically, is the use of the E-Prop just a bolt on installation which allows use of the Neuform spinner and spinner tube if the spacer is installed?  With the low weight (inertia) and Madhatter's comments on less vibration, I'm wondering if prop balance is not required?  What are your thoughts on the prop not having a leading edge protector strip?

Hi Dick,

yes,just a bolt on ..without any spacer as you order the ‘extended hub’. Everything is balanced (with spinner if ordered )at factory before shipping.

The leading edge protection is incorporated in the material. Go see the video .impressive .. “Nanostrength“ they call it

http://www.e-props.fr/16/blindage/nanostrength_for_epoxies.pdf

and you can also ad tapes for better protection  ( rain flying,floats).

 

Madhatter,I’m glad that you are happy with the result.

I will install mine in May ....looking forward to feel the difference

 

 

 

 

[Ed Cesnalis]

18 hours ago, Roger Lee said:

"It is interesting that the advice hear has 'crept up' to a higher RPM and is offered as recommendation without the logic behind it."

Please elaborate and don't forget the logic.

 

Remember "Woodstock Comes Alive".

5,500 RPM at WOT, as a prop pitch setting has always been best power within the 5,500 limitation.  It translates to best speed and climb.

The newer value being used by you 5,650 at cruise altitude requires a retarded throttle to limit RPM (and power / speed ) to comply with the limitation.

Flying around with a retarded throttle in order to achieve best speed is analogous to flying around with a dirty / partially clogged air cleaner that limits power.

The 912ULS power/torque curve chart confirms that 5,500 @ WOT is your highest power setting.

[Roger Lee]

Hi Ed,

"5,500 RPM at WOT, as a prop pitch setting has always been best power within the 5,500 limitation.  It translates to best speed and climb."

This  just isn't true. You need data, test and research to back it up.

I did a 14 prop research project with 4 identical CTSW's. The only prop study like it in the US and maybe the world. It took months. You fail to take into account many human factors, aircraft factors, weight of aircraft and atmospheric factors which either need to be removed and accounted for. You need to quit looking at the Rotax book data because it isn't based on a ground adjustable prop and HP and torque are calculated on the ability of an engine being able to obtain 5800 rpm at times and with a CS prop.

Everyone that checks a prop difference may have different people setting up the prop, different pilot flying and techniques, different times of the day, different atmospheric conditions, ect...

This study was done with only one person setting up the props, all CT's taking off together in pairs side by side, all take off and flight parameters regulated by one person, the same time of day, side by side flight in climb and cruise and as many factors dealt with as possible without a robot doing everything.

Bottom line Rotax's chart is not for a ground adjustable prop and this absolutely bares out with real research data. I have actually research test data and see no one else that has done any thing like this. Not even the prop companies have ever done this. I sent my data to them all and they are the ones that sent me all the props.

p.s.

The worst climb prop is the Warp over all the 13 other props 2 or 3 blade.

[Ed Cesnalis]

9 minutes ago, Roger Lee said:

Bottom line Rota's chart is off fort a ground adjustable prop and this absolutely bares out with real research data.

You are making that up Roger.  The power / torque curves published so long ago come from a dyno and do not apply to a prop type (you meant to say an in flight adjustable)

Power curved upwards with RPM and peak occurred at the 5,800 redline.  5,500 is the best power setting only with the 5,500 limitation.  To realize more power at 5,650 RPM you would need to exceed the 5,500 limitation and when throttled back to 5,500 you are at a reduced power setting.

5,650 is actually a very good setting for lower altitude pilots but not because its the fastest or best climbing, your testing gave  you a good result but lacked precision and you are changing power settings based on your testing.

[Tom Baker]

Ed, I think that you are correct, in that the best speed will be achieved with the prop set for 5500 rpm full throttle level flight. That being said any prop that the pitch can't be changed in flight is a compromise. Climb performance will be better with a prop that is pitched to 5650 WOT level flight. The reason being is the engine will turn a higher RPM under the load of the climb compared to the one pitched for 5500. More RPM means more HP. I bet climb rate could be increased more if the prop was pitched to 5800 level flight. My favorite number is a little lower than Roger's, I like 5550-5600. What we are looking for is the best compromise between speed and climb performance.

If, and I emphasize the "IF" this new prop can close the gap between WOT RPM during climb and WOT RPM level flight then it will improve the performance of our little airplanes.

[Roger Lee]

"You are making that up Roger."

Nope.

This is just like back in 2007 when you told me your over pitched warp gave you better performance than 5500 WOT at your average altitude. You flattened the pitch and then you came back to the forum and stated "Woodstock comes alive".

Not to mention the results from them are not real world flying with different props, pilots and atmospheric conditions air intake, ect.... I mean it is done on a dyno with absolute control over air intake factors (which you don't have), over prop setup, atmospheric conditions.  When I did dive compressors and looked at companies data they all told me the published out come for out put is calculated under perfect circumstances and when you start to add or remove fittings and the like or in a different atmospheric condition those calculated numbers aren't the same which a months worth of testing on flow gauges bore out. Mfg's set up test results in absolute controlled best conditions or they are just calculated by an engineer.

See i don't believe anybody and always have to test things under controlled circumstances. Did it on the fire department to.

 

Here's my challenge to you. I'm even willing to put up a month's salary against yours on the results, but I already know the results. Take Woodstock up to your average altitude (around 11.5K). Make sure you get 5500 WOT at that altitude. Record all your take off numbers and then numbers at that altitude. The either borrow or buy (it would be worth your while) a Sensenich 68" 3 blade prop. Install it and make sure at 11.5K it gets 5600-5650 rpm WOT. Then on take off again record your numbers and at altitude. Remember I had a Warp for a couple years to. There is absolutely no doubt you will see a difference.

p.s.

I already did this test.

[Roger Lee]

Also I agree with Tom. Prop pitch should be set up for specific needs, but without shooting yourself in the foot thinking what you did was better and without real time test data on that plane it's just flawed data for many.

[Ed Cesnalis]

27 minutes ago, Roger Lee said:

This is just like back in 2007 when you told me your over pitched warp gave you better performance than 5500 WOT at your average altitude. You flattened the pitch and then you came back to the forum and stated "Woodstock comes alive".

time changes memory I guess.  I worked out that I needed 5,5000 @ 10,000'DA with Gary Anus before I barely knew you.  The posting you now take credit for was a report on how well it worked.

[Ed Cesnalis]

29 minutes ago, Roger Lee said:

Here's my challenge to you. I'm even willing to put up a month's salary against yours on the results, but I already know the results. Take Woodstock up to your average altitude (around 11.5K). Make sure you get 5500 WOT at that altitude. Record all your take off numbers and then numbers at that altitude. The either borrow or buy (it would be worth your while) a Sensenich 68" 3 blade prop. Install it and make sure at 11.5K it gets 5600-5650 rpm WOT. Then on take off again record your numbers and at altitude. Remember I had a Warp for a couple years to. There is absolutely no doubt you will see a difference.

proving the relative performance of a Warp drive is irrelevant.  It's not about the prop but about the RPM that is until the prop can flex under load.

[Roger Lee]

7 hours ago, Ed Cesnalis said:

proving the relative performance of a Warp drive is irrelevant.  It's not about the prop but about the RPM that is until the prop can flex under load.

My 4 month 14 prop research still stands and I'll post it against any single entity since I'm the only one who has done a project like this in the US. Rotax did no study like this with multi props or ground adjustable in real time on real planes.

 

Warp is irrelevant for rpm  except in your case where you want the best to be at 5500 WOT. That won't happen with a Warp or at 5500 at your altitude.

Flex didn't make any difference. Of those 14 props I had long and short stiff and flexible. Unless someone here can repeat a test like this anything is speculation.

 

Gary Anus knew nothing of this until I told him. You argued with me back then too about prop pitch, but you thought less than 5500 was better until you tried it and then you proved it to yourself again at the Page Fly-In over the Grand Canyon when we were flying side by side and you pulled away because my prop wasn't pitched for 11.5K altitude and yours was.

This is where your cheer of "Woodstock Comes Alive" comes from and it was 2007. The old forum when you finally tried a flatter pitch. You thought Woodstock was a dog and when you flattened the pitch you had a new pup.

 

I'll get with Tim and see if we can track down the old forum from the R. Heller days. That was CTFlyer.com and you were #8 to sign on and I was #11 and then it started to grow.

[Roger Lee]

Just got off the phone with Tim. he was on the old forum in the early days to. He said we can't recover the old forum due to R. Heller running it off a computer in his home and that domain name and computer are most likely in the trash.

He does remember that conversation and the post about Woodstock comes alive and why.

I don't think we can beat this horse with prop pitch anymore and each will have to reach their best conclusion.

 

 

[Ed Cesnalis]

38 minutes ago, Roger Lee said:

Just got off the phone with Tim. he was on the old forum in the early days to. He said we can't recover the old forum due to R. Heller running it off a computer in his home and that domain name and computer are most likely in the trash.

He does remember that conversation and the post about Woodstock comes alive and why.

I don't think we can beat this horse with prop pitch anymore and each will have to reach their best conclusion.

 

 

My CT wasn't my first Rotax powered, ground adjustable setup.  I had optimizing pitch for best power figured out in the early 1990s.  I simply didn't need anyone to tell me how to re-pitch.

[Runtoeat]

Roger, what is you opinion of the E-Prop?   I don't think that you have tested this prop but curious what you think based on the testing you did and the comments and published data about the E-Prop performance.

Madhatter or Jacques, not sure if you guys are experimental?  I believe that Jacques states that FD now offers the E-Prop.  Is this only for Europe?  If only for Europe, has FD USA given any opinions on whether the E-Prop can be installed here in U.S without authorization or if it will require CT owners to request a MRA?

[Madhatter]

I am experimental. Smooth air today 60°F, 1500 msl,   5200. 114 kts, IAS,  5400. 117kts IAS,  5500 119kts IAS.      WOT of 5400 or 5600 will not make these numbers, 5500 is the best.

One thing I noticed if the carb sync is off even a small amount you will get a lot of high frequency vibration around 2500 rpm, something that is not as noticable on a Neuform, I am sure is due to low inertia. I have done about 8 test flights and am satisfied with the prop so far.

[Jacques]

mine is ‘Advanced Ultralight’..so,needed  ‘some kind’ of permission from FD.

Tom P. told me about the factory install and that the french distributor is pushing for it..as it performed just better.

Performance is not just speed [not much] & climb but Moment of Inertia & vibration.

having knowned this prop before ,I would have keep the 80 hp

we are flying one of the best designed light planes, why not using one of the best designed propeller ?

[Runtoeat]

Good info on E-Prop.  Thanks.  If this prop is demonstrating improved performance combined with a safe history being used in Europe perhaps FD USA will approve the MRA for install of this prop on U.S. CT's.

[Ed Cesnalis]

15 minutes ago, Runtoeat said:

Good info on E-Prop.  Thanks.  If this prop is demonstrating improved performance combined with a safe history being used in Europe perhaps FD USA will approve the MRA for install of this prop on U.S. CT's.

I hope so.

[FlyingMonkey]

I live in lower altitudes, with a field elevation of 940ft.  I also will always take climb over cruise speed, all day every day.  As I like to say: "Nobody ever got killed flying an airplane with too much climb performance."  I have a Neuform prop.

The above stipulated, I really like having a WOT at 2000-3000ft of around 5600-5700rpm, and actually like 5700 over 5600, 5650 being a good number.  I find this gives me better climb performance, and also gives me great cruise of 5500rpm+ if needed up to 10,000ft or more.

I have never had any issue being able to hit 120kt TAS or more at any altitude, and never have to use 5500rpm to get there.  But I do realize that my CT is faster than most, due to rigging or just phase of the moon when it was built.

[Roger Lee]

Just trying to be the analytical realist here.

From all the different prop Mfg claims and what I've read so far I don't see any real performance difference. I see a couple of observations, but no real comparative test against multiple props. All prop companies claim their's is better. Just ask them.

Just remember the human factor is the biggest error correction and control problem when judging prop and individual aircraft performance differences plus gauge inaccuracies between each aircraft. 2-5 knot difference in one CT may amount to 0-2 in another.

I'm not saying this prop is bad and just not convinced on better performance since none out of 14 others were better than their competitors. 

[Madhatter]

Try one, the difference is significant in performance, no splitting hairs is necessary to see it. I have never seen a prop designed like this, even the sound is very different. 3 people have told me that it sounds more like a conventional aircraft and not a pool toy . The wot target for this prop is 5500.  5400 or 5600 will not perform , I have tried them all. Also all my numbers are indicated airspeed, not true airspeed. You only have to be a pilot good enough to fly straight and level and read a tach to see it, you don't have to be Chuck Yeager on this one, but it might help. If anyone is unhappy with the prop it can be returned within 6 months for full refund. This refund policy is e-mailed on my correspondence by the company CEO. The customer service with this company is with the CEO and is impressive, no delays in e-mail, sometimes in only minutes, once even on a sunday.( their time zone). Time will tell on this prop but so far I am  impressed with it.

Edited December 26, 2018 by Madhatter
Additional info

[Madhatter]

Roger, all my comparative data is same plane same pilot, same oat, etc. Trying to make comparisons using multiple planes and pilots will not give good data. Sometimes new technology works, otherwise we would still be driving to the airport in our model T to get into our Wright Flyer. However my wife said she would like to have a Model T. The only problem is that I would probably  want to modify it

[Roger Lee]

Because of my analytical and curious  nature and desire to test everything and because I have found so many claims in products like props to be just that "mfg claims" I tend to be skeptical until proven otherwise.

I'm not saying it doesn't work or it's bad advertising from the MFG or anything or the kind. I'm just skeptical until proven otherwise. Being skeptical and testing is what makes things progress and weeds out the not so good ideas that pop up from some Mfg's in our life.

The E-Prop may be everything that people claim, but I'd like to see some real time side by side comparison with other props.

[solarguy54]

Since we use our CTs as rentals and for student training, I don't have ours set up to do >5500 RPM at WOT.  According to the Rotax manual, you've got 5 minutes grace between 5500 and 5800. And "never exceed 5800." Though you can go to 6200 for a minute without an inspection. 5800-6200 for more than a minute, inspect pushrods. One minute and hit 6500, inspect push rods. More than a minute above 6500, inspect/rebuild whole engine. 

I always thought the 100 HP claim was kind of their marketing department spin since the 912 is claimed to be a 100 HP engine, but only develops 100 HP at 5800 RPM. So I guess it would be more accurate to say that it's a 5 minute 100 HP engine...

I remember Brian Carpenter in class showing a graph that I think overlaid HP and torque. Peak torque is just under 4900 RPM at about 128 NM. Peak HP is at 5800 RPM with 5500 continuous delivering about 93 HP. I think I remember Brian saying that optimum performance is about 5250. Anyone else remember this?

Sid Lloyd
LSRM A/WS

[Madhatter]

Different propellers respond differently to the engine due to blade airfoil design and pitch. With wot of 5500 on the e prop the climb rpm is about 5300. This shows that the blade pitch is changing to accommodate  the increased load as per the design of the propeller. It is acting more like a variable or constant speed propeller. My Neuform prop at wot of 5650 only got 5000 for climb, a more significant load on the engine. The e-prop website data on this has very in depth analysis on this, even enough to satisfy the obsessive engineer ( I am not that type of engineer).

[Madhatter]

Just to clarify, when I refer to pitch change it is really the efficiency of the prop for all the different flight regimes.  They call it ESR effect and it is the aerodynamic design which allows better rpm efficiency under all conditions.  When you look at one you will see a significant difference from normal props.