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lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Tue Mar 10, 2009 6:44 pm Post subject: Static rpm - warp drive/912ULS

Hi all,



I asked this over on the titan list, but thought I'd ask you guys here that run the warp drive on the 912ULS.



I got mine fitted to my engine this evening and at this point, it's set to about 5350 static RPM. Mine's a 68" 3 blade.



My question is, what do you guys aim for pitch-wise and/or static rpm wise? 



PS the fasteners I got are a perfect fit for attaching the extension, for those of you who remember my thread on the bolts....



LS

_________________
LS
Titan II SS

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Tue Mar 10, 2009 6:53 pm Post subject: Static rpm - warp drive/912ULS

> I got mine fitted to my engine this evening and at this point, it's set 

to about 5350 static RPM. Mine's a 68" 3 blade.

 	  Quote: 	
		  

 My question is, what do you guys aim for pitch-wise and/or static rpm 

 wise?



 PS the fasteners I got are a perfect fit for attaching the extension, for 

 those of you who remember my thread on the bolts....



 LS


	




That's a good place to start for me.  Usually, 5400 static will give me 5500 

WOT straight and level flight.  That gives me the best of both takeoff and 

cruise.



May be different for the Titan, because it is so much cleaner than the 

mkIII, but I'd give it a shot and see how it works out.



Would not be surprised if you had to pull a little more pitch into it.  Not 

having experience with the Titan, I could only venture a guess.



john h

mkIII

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Tue Mar 10, 2009 7:09 pm Post subject: Re: Static rpm - warp drive/912ULS

 	  John Hauck wrote: 	
		  



That's a good place to start for me.  Usually, 5400 static will give me 5500 

WOT straight and level flight.  That gives me the best of both takeoff and 

cruise.



May be different for the Titan, because it is so much cleaner than the 

mkIII, but I'd give it a shot and see how it works out.



Would not be surprised if you had to pull a little more pitch into it.  Not 

having experience with the Titan, I could only venture a guess.



john h

mkIII 	




Ok, thanks john. If the winds lay down at all tomorrow I may take it around the patch to see what I got. Just wanted to know if I wasn't underpropped before flying it, don't want it to run away on me....



If all goes well with work, wx, etc, I'm hoping it takes me and the plane to MV in May..



LS

_________________
LS
Titan II SS

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Tue Mar 10, 2009 7:22 pm Post subject: Static rpm - warp drive/912ULS

> If all goes well with work, wx, etc, I'm hoping it takes me and the plane 

to MV in May..

 	  Quote: 	
		  

 LS


	


I bet it will.



Warp Drive Props have certainly pushed my around all over the place, and 

back...



john h

mkIII

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Tue Mar 10, 2009 8:10 pm Post subject: Re: Static rpm - warp drive/912ULS

I like my Warp Drive prop a lot, I get a static RPM of about 5200, which is about the same in climb.   Your titan is a little faster, but I think the 5350 RPM you have now is a good safe place to start.  It might be a little high for your fast Titan, but if so you will know it long before you over rev the engine.   Take it up, see what the RPM is at cruise, and then adjust from there if need be.   I am looking forward to hearing your report on the prop.



Mike

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Wed Mar 11, 2009 5:47 am Post subject: Re: Static rpm - warp drive/912ULS

 	  JetPilot wrote: 	
		  I like my Warp Drive prop a lot, I get a static RPM of about 5200, which is about the same in climb.   Your titan is a little faster, but I think the 5350 RPM you have now is a good safe place to start.  It might be a little high for your fast Titan, but if so you will know it long before you over rev the engine.   Take it up, see what the RPM is at cruise, and then adjust from there if need be.   I am looking forward to hearing your report on the prop.



Mike 	




Ok, thanks Mike. Winds wont let me try it today. I might add another degree and see what I get in static. I usually climb out at about 80mph for safety reason even tho Vy is about 65, so as John said I may need a little more pitch.



One other question as I'm still learning my way around the 912. Is redline 5800? The documentation says max continuous is 5500 but "takeoff rpm" is 5800. Says you can run at this for 5 mins. 



So sounds like 5800 is really the redline but you can still run for a short period at or below that, is that right?



We may have a couple other locals who may go to MV too, so we might have a Posse for the trip....



Thanks,



LS

_________________
LS
Titan II SS

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Wed Mar 11, 2009 6:23 am Post subject: Static rpm - warp drive/912ULS

> One other question as I'm still learning my way around the 912. Is 

redline 5800? The documentation says max continuous is 5500 but "takeoff 

rpm" is 5800. Says you can run at this for 5 mins.

 	  Quote: 	
		  

 So sounds like 5800 is really the redline but you can still run for a 

 short period at or below that, is that right?



 We may have a couple other locals who may go to MV too, so we might have a 

 Posse for the trip....



 Thanks,



 LS


	


All 912 series engines are redlined at 5,800 rpm for a maximum of 5 minutes.



Maximum continuous cruise rpm is 5,500 rpm.  This is the red line for max 

continuous cruise.



If you are equipped with an inflight adjustable prop, you could use 5,800 

rpm for 5 minutes max, then pull in pitch to run 5,500 rpm or less.  The 912 

series engines are designed to operate at 5,500 rpm, even if that means you 

are flying at WOT, as long as temps are kept in the green.  It ain't gonna 

hurt the engine.  Turning it too slow under load is much harder on it.



I prop my ground adjustable Warp Drive Prop to attain 5,500 rpm, WOT 

straight and level flight.  If I do this, then I get the best climb and 

cruise available with this prop.



If I should prop for 5,800 rpm max, I would have fantastic climb and poor 

cruise speed.



If I over load the engine with too much pitch, won't pull 5,500 rpm WOT in 

straight and level flight, I am loading the engine more than necessary, not 

climbing as well.



I run into a problem flying West from a sea level base.  I prop for sea 

level.  By the time I get to MV, the field elevation is 5,200 feet.  My 

engine won't pull 5,500 rpm straight and level WOT.  However, I take that 

into consideration when I fly at higher elevations and it works out ok.



I flew Rick Neilsen out of MV, and Larry Cottrell.  Both of these guys are 

not fly weights.  I think the VSI was indicating 500 to 800 fpm climb.  I 

don't know how accurate the VSI is.  Never checked it, but it gives me an 

idea of how well my airplane is performing.  If there is a big change in 

performance, then I am aware of it.  The other day my mkIII was pegging the 

VSI at 2,000 fpm with me and 60 lbs of fuel.



I encourage you and your posse to decend upon us at MV.  This will be number 

7.  We have met a lot of folks at MV.  Look forward to seeing them each 

year.  Try to get there on Thursday or Friday, and stay until Sunday, if you 

can.  I think you will get a lot more out of the flyin by being able to 

relax and spend time with this group of Kolb enthusiast.



I prop my Warp Drive for 5,400 rpm static.  On take off, as soon as the 

aircraft starts rolling and getting cleaner air through the prop, rpm is 

pulled down to 5,300 rpm.  Usually, 5,300 rpm is what it climbs at around 60 

mph.



A unique characteristic of the taper tip Warp Drive prop is its capability 

to change pitch slightly.  Upon reaching cruise altitude and speed, I can 

reduce power to 5,000 rpm, normal cruise rpm for me, and the Warp Drive will 

maintain this cruise speed.



Take care,



john h

mkIII

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Wed Mar 11, 2009 6:46 am Post subject: Re: Static rpm - warp drive/912ULS

 	  John Hauck wrote: 	
		  



I encourage you and your posse to decend upon us at MV.  This will be number 

7.  We have met a lot of folks at MV.  Look forward to seeing them each 

year.  Try to get there on Thursday or Friday, and stay until Sunday, if you 

can.  I think you will get a lot more out of the flyin by being able to 

relax and spend time with this group of Kolb enthusiast.

	




Well that's the idea . Dennis Kirby and I are already kicking the idea around. He's in a mark III and a couple of the other locals in the Albuquerque area have expressed interest. Perhaps the intrepid trikers down in Belin could be persuaded as well. Those guys are among my heros as well as they go all over the place in their trikes.



 	  Quote: 	
		  

I prop my Warp Drive for 5,400 rpm static.  On take off, as soon as the 

aircraft starts rolling and getting cleaner air through the prop, rpm is 

pulled down to 5,300 rpm.  Usually, 5,300 rpm is what it climbs at around 60 

mph.



A unique characteristic of the taper tip Warp Drive prop is its capability 

to change pitch slightly.  Upon reaching cruise altitude and speed, I can 

reduce power to 5,000 rpm, normal cruise rpm for me, and the Warp Drive will 

maintain this cruise speed.



Take care,



john h

mkIII 	




Ok, thanks for the info. You're one of the true go-to guys on the 912 for sure. 



I was previously doing around 5300 to 5400 on climbout with the IVO and keeping it at at least 5000 to 5100 in cruise. So hopefully I wasn't overloading it (JD trained me on this when he transitioned me to the plane but I may have absorbed the information wrong).



It's funny because i ran this exact same prop on my 503 on my old FS II. It was my first Warp Drive and it was a great prop. Sure miss that plane, but I'm also sure Bob is having a ball with it.



Already with the runups I did last night, the WD is quieter than the IVO by a bunch and the engine idles noticeably happier probably due to the slightly less rotating mass.



Going to request vacation from the bossman next week....



LS

_________________
LS
Titan II SS

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Wed Mar 11, 2009 7:48 am Post subject: Re: Static rpm - warp drive/912ULS

I set my prop based on John Haucks advice, which makes perfect sense, to adjust the pitch so that the engine is running at 5500 RPM wide open throttle, at max level flight speed.  My RPM's  are just a hair slower than Johns, I see around 5200 RPM on climbout, and about the same static.  



I tried setting the 912-S for a 5800 RPM climbout, the climb performance was improved a bit, but cruise was HORRIBLE !!  The plane was slow and needed to have a bunch of RPM just to maintain a slow cruise.  I only flew it like that a couple times before I changed the pitch to where it is now. I'm just as happy not to ever run my Rotax 912-S above 5500 RPM, I want my engine to last a long time, and there is very little more power to be gained by that extra 300 RPM.  5800 RPM cant be great for the engine also long term, there is a reason Rotax limits this RPM to 5 minutes.  Most engines will last longer if you don't push them to their absolute limits.  



Mike

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Wed Mar 11, 2009 7:57 am Post subject: Re: Static rpm - warp drive/912ULS

 	  JetPilot wrote: 	
		  I set my prop based on John Haucks advice, which makes perfect sense, to adjust the pitch so that the engine is running at 5500 RPM wide open throttle, at max level flight speed.  My RPM's  are just a hair slower than Johns, I see around 5200 RPM on climbout, and about the same static.  



I tried setting the 912-S for a 5800 RPM climbout, the climb performance was improved a bit, but cruise was HORRIBLE !!  The plane was slow and needed to have a bunch of RPM just to maintain a slow cruise.  I only flew it like that a couple times before I changed the pitch to where it is now. I'm just as happy not to ever run my Rotax 912-S above 5500 RPM, I want my engine to last a long time, and there is very little more power to be gained by that extra 300 RPM.  5800 RPM cant be great for the engine also long term, there is a reason Rotax limits this RPM to 5 minutes.  Most engines will last longer if you don't push them to their absolute limits.  



Mike 	




Ok, thanks Mike... 



Yeah this was one of the problems I was having with the IVO - ironically at only 66", it was a little overpropped and would start to unload too much once I got over about 80mph. So I had to load it down too much for takeoff to keep it from overspeeding in cruise or flatten it out to get a good 5300 to 5400 scream on takeoff. But set that way it would easily try to overspeed at WOT in the air....



So far, I can't say enough nice about the construction of the HPL hub and the extension. It's all such a nice precision fit onto the flange that it's basically cake to put on. I had the whole thing installed in about 1/2 hour.



Can't wait to fly it now.... but Ill have to due to hurricane winds....



LS

_________________
LS
Titan II SS

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Fri Mar 13, 2009 8:23 am Post subject: Re: Static rpm - warp drive/912ULS

 	  JetPilot wrote: 	
		  I set my prop based on John Haucks advice, which makes perfect sense, to adjust the pitch so that the engine is running at 5500 RPM wide open throttle, at max level flight speed.  My RPM's  are just a hair slower than Johns, I see around 5200 RPM on climbout, and about the same static.  

	




FWIW, I got to do some high speed taxi tests last night - it was too windy and dark to actually take the plane up. 



but my jaw dropped when I saw how far the RPM's went down as soon as airflow started going through the prop disk. At 5300 or so static, by the time the ASI started indicating, it'd loaded down to nearly 4900 rpm.... good thing I didn't actually try to blast off.



Took 2 degrees of pitch out and tried again. Now it loads down to about 5290 or thereabouts on the roll, so that's probably reasonably close to where it should be.



If I can ever get daylight and reasonable winds to coincide, I have it set well enough to fly at this point I think.



I should add that once the blades start to "catch", the thrust is significantly more than I got with the IVO. So it'll be interesting to see what I get once I get airborne....



LS

_________________
LS
Titan II SS

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Fri Mar 13, 2009 12:39 pm Post subject: Re: Static rpm - warp drive/912ULS

That seems like a good place to start Lucien.  That RPM is pretty typical for many different aircraft climbing out on the 912-S with a fixed pitch prop.  Once you get in level flight, open the throttle wide open level flight it gets going as fast as its going to go, and that should be 5500 RPM.



Since your Titan is fast, your RPM will increase with speed more than ours do on the Kolbs.  My guess is that you might have to pitch the prop a bit more ???  But I would fly it the way it is now and see what you get, the RPM you have now sounds great for a flight test.   I have experimented with different pitches quite a bit on my 912-S / warpdrive setup.  If you dont get it right, the cruise performance can be very bad, but you would have to be way way off for the plane not to fly well and scare yourself     I have heard of some airplanes being around 5100 RPM or even a bit less on climbout.   Hope you get a good flying day soon, I am anxious to hear your report on how the Warp compares to the IVO.



Mike

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Fri Mar 13, 2009 1:09 pm Post subject: Re: Static rpm - warp drive/912ULS

 	  JetPilot wrote: 	
		  That seems like a good place to start Lucien.  That RPM is pretty typical for many different aircraft climbing out on the 912-S with a fixed pitch prop.  Once you get in level flight, open the throttle wide open level flight it gets going as fast as its going to go, and that should be 5500 RPM.



Since your Titan is fast, your RPM will increase with speed more than ours do on the Kolbs.  My guess is that you might have to pitch the prop a bit more ???  But I would fly it the way it is now and see what you get, the RPM you have now sounds great for a flight test.   I have experimented with different pitches quite a bit on my 912-S / warpdrive setup.  If you dont get it right, the cruise performance can be very bad, but you would have to be way way off for the plane not to fly well and scare yourself     I have heard of some airplanes being around 5100 RPM or even a bit less on climbout.   Hope you get a good flying day soon, I am anxious to hear your report on how the Warp compares to the IVO.



Mike 	




Well tomorrow we might get a break in the winds, so perhaps I can go around the patch with it.



Part of the complication is my altitude (7000'MSL), which turns the motor into about a strong sea-level 582 rather than a 912uls. A regular kick around the patch sightseeing has me close to 10,000' and the houses and mountains are sometimes still too big. So even with the IVO when I had it flatted out to 5400 in level flight it could barely do 100mph indicated (tho about 110 true). So the speed range isn't too terribly much more than even a Mark III. But I did go with a 68" to start with, so it would run more pitch and hopefully have more cushion for speed range.



I'm less concerned about cruise than I am climb, but I don't want the engine to be able to overspeed in level flight (i.e. if the throttle cable breaks). So I'll just have to work on it until it's right.



I'm blazing a little bit of a trail since a 68" diameter warp drive hasn't been tried on a titan yet to my knowledge (only the SS has room for more than a 64"). 



The thrust when the blades unstall on the ground runs I did last night is significantly more than the IVO, which starts off strong but then fades as you gather speed.  So hopefully it'll be more efficient in the air also.



LS

_________________
LS
Titan II SS

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Fri Mar 13, 2009 3:43 pm Post subject: Re: Static rpm - warp drive/912ULS

The bigger diameter should be much more efficient at that your speed than a 64 inch prop.  I have a 70 inch on my prop.



How much clearance do you have left to the tail boom tube with the larger prop ?



Mike

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Fri Mar 13, 2009 5:16 pm Post subject: Re: Static rpm - warp drive/912ULS

 	  JetPilot wrote: 	
		  The bigger diameter should be much more efficient at that your speed than a 64 inch prop.  I have a 70 inch on my prop.



How much clearance do you have left to the tail boom tube with the larger prop ?



Mike 	




There's still a good 4 or 5". I measured it a while back and found that a 72" could fit and there'd still be like 2 inches of clearance. I don't know what the limits of flex are on the mounts and the rest of the plane tho so I'd say 70 is the max safe diameter.



I was thinking about going with a 70" but opted for 68" to allow a little more pitch for the wider speed range.



I'll have to fly it and see how it does.



I actually had this exact same prop on my FS II (tho it was right hand instead) and it worked great. It was my first warp drive prop and it was about as perfect as you can get for the 3.47 C box and that plane.



Still miss it which is why one day I'd like to do a firefly/447....



LS

_________________
LS
Titan II SS

Thom Riddle

Joined: 10 Jan 2006
Posts: 1597
Location: Buffalo, NY, USA (9G0)

Posted: Sat Mar 14, 2009 4:08 am Post subject: Static rpm - warp drive/912ULS

Out Allegro was pitched so that typically the 912UL ran around 4900

rpm during take-off run. In straight and level flight at full throttle

at our typical density altitude it would top out at 5500 rpm and about

125 mph TAS. I expect your Titan will be in this speed range too. The

faster the airplane the more difference you can expect between the

take-off run rpm and Vh rpm.



Our RANS has a fixed pitch (66x52) Tennessee climb prop so we get a

lot higher take-off rpm and can easily run past redline during cruise

if not paying attention, even at high density altitudes.



Thom in Buffalo

_________________
Thom Riddle
Buffalo, NY (9G0)

Don't worry about old age... it doesn't last very long.
- Anonymous

John Hauck

Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

Posted: Sat Mar 14, 2009 5:43 am Post subject: Static rpm - warp drive/912ULS

> Our RANS has a fixed pitch (66x52) Tennessee climb prop so we get a

 	  Quote: 	
		   lot higher take-off rpm and can easily run past redline during cruise

 if not paying attention, even at high density altitudes.

 

 Thom in Buffalo

 
	




Is there a reason for leaving that prop on the Rans?



john h

mkIII

_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Sat Mar 14, 2009 7:58 am Post subject: Re: Static rpm - warp drive/912ULS

 	  Thom Riddle wrote: 	
		  Out Allegro was pitched so that typically the 912UL ran around 4900

rpm during take-off run. In straight and level flight at full throttle

at our typical density altitude it would top out at 5500 rpm and about

125 mph TAS. I expect your Titan will be in this speed range too. The

faster the airplane the more difference you can expect between the

take-off run rpm and Vh rpm.



Our RANS has a fixed pitch (66x52) Tennessee climb prop so we get a

lot higher take-off rpm and can easily run past redline during cruise

if not paying attention, even at high density altitudes.



Thom in Buffalo 	




Eeeyikes, 4900 strikes me as really lugging it.... That can't be good for the motor..... Tho I guess if you have that wide of a speed range you probably don't have much choice ?



My problem is our altitude so I need as much climb as I can possibly get for safety reasons, even with our mile plus long runways.



With my FSII, I had that sucker turning 6300 on the takeoff roll and in climbout about 6400. The plane was actually trimmed to fly at about 70 but I kept it at 60 to 65 with about 5200 to 5400 cruise. 



It could have easily overspeeded in level flight, but with a climb rate of about 300 fpm max, I was happy to have that baby putting out max power in a Vy climb (which IIRC, was about 40 to 45mph?). 

At approx 377 power levels, that was ok with me .



My current plane I'm perfectly content to cruise along at 90 or even 80 and don't care a great deal about going really fast. I think it's the UL'er/Kolber in me....



So I'll just have to see what I get in flight. Winds look low today so I may head out and have a go here in a bit. 



LS

_________________
LS
Titan II SS

lucien

Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

Posted: Sat Mar 14, 2009 6:48 pm Post subject: Re: Static rpm - warp drive/912ULS

Just in case anyone's interested in a PIREP on the Warp Drive,



I finally flew around the patch with the new WD. It really does work like a CS prop! I don't recall this affect as much on my FSII, but on the 912uls it's very noticeable. Everything in climb between 65 and 80 mph stayed between 5350 and 5420 rpm or thereabouts. 



The pleasant surprise was on downwind, when I noticed I was at almost 95mph at my usual throttle setting but was still only turning just under 5000. (normally 5100 with the IVO unless I add in more pitch). I'd usually just be breaking 85 if I held 5000.



So the speed range is quite a bit wider than the IVO which is really nice. The performance is slightly better too, especially over a wider range of airspeeds where it maintains a good load on the motor and good thrust.



The less rotating mass over the IVO is very noticeable, especially at idle which is much smoother now.



Overall a very good upgrade so far. Still have to do more flying at cruise to see what I got there...



LS

_________________
LS
Titan II SS

Thom Riddle

Joined: 10 Jan 2006
Posts: 1597
Location: Buffalo, NY, USA (9G0)

Posted: Sun Mar 15, 2009 3:59 am Post subject: Re: Static rpm - warp drive/912ULS

John,



We plan to change the climb prop eventually for an adjustable pitch. We've been doing a lot of other refinements that were more critical but the prop change is getting closer to the top of the list.

_________________
Thom Riddle
Buffalo, NY (9G0)

Don't worry about old age... it doesn't last very long.
- Anonymous

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