Matronics Email Lists :: View topic

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

more prop test info

Matronics Email Lists Forum Index -> Lightning-List

View previous topic :: View next topic

Author Message

davemcc

Joined: 28 Feb 2007
Posts: 74

Posted: Thu Aug 06, 2009 4:25 pm Post subject: more prop test info

Buz

 I put  the 62FK60 on today.  Don't know what to think just  yet.  Testing was done at 3,000 ft, 85 degrees and indicated  only

 new prop-----------

 RPM                 Fuel  burn              Speed mph

 2850                  8.1                       152

 2750                  6.6                      146

 2650                  5.7                       140

 WOT 3,000 rpm, static 2560 rpm at WOT the EGT was 1450 degrees

  

 composite ground adjustable (old prop)

 2850                  6.1                       145

 2650                  5.1                       137

 WOT 3200 RPM

  

 I reached the 150 mph point but lost 2 gal per hr.  Short story  long--- what are you running for jetting and I am thinking this may be an  altitude prop--not used for skud running?  Nick or Buz, what jetting is  needed?

 Thanks for any advise

  

 Dave McC

 [quote]   ---

IFLYSMODEL(at)AOL.COM
Guest

Posted: Thu Aug 06, 2009 4:55 pm Post subject: more prop test info

Hey Dave: It looks like your speeds are very comparable to those that Buz  posted. (His were true and yours were indicated). I would estimate that you  would have to add approximately 10 mph to your figures to get the true speed. It  will be interesting to see what the fuel jetting should be. I am sure that Nick  will ask what the temperatures were.

 Lynn 

  

  In a message dated 8/6/2009 8:26:01 P.M. Eastern Daylight Time,  corky(at)hbci.com writes:

 [quote]   Buz

   I put  the 62FK60 on today.  Don't know what to think just    yet.  Testing was done at 3,000 ft, 85 degrees and indicated    only

   new prop-----------

   RPM                   Fuel    burn                Speed mph

   2850                    8.1                         152

   2750                    6.6                      146

   2650                    5.7                         140

   WOT 3,000 rpm, static 2560 rpm at WOT the EGT was 1450 degrees

    

   composite ground adjustable (old prop)

   2850                    6.1                         145

   2650                    5.1                         137

   WOT 3200 RPM

    

   I reached the 150 mph point but lost 2 gal per hr.  Short story    long--- what are you running for jetting and I am thinking this may be an    altitude prop--not used for skud running?  Nick or Buz, what jetting is    needed?

   Thanks for any advise

    

   Dave McC

   [quote]     ---

checkpoint2(at)comcast.ne
Guest

Posted: Fri Aug 07, 2009 11:12 am Post subject: more prop test info

Hey Dave what index was the adjustable pitch set at?  Bob Haas  N330BH Thanks.  

         

  

From: owner-lightning-list-server(at)matronics.com [mailto:owner-lightning-list-server(at)matronics.com] On Behalf Of Dave

 Sent: Thursday, August 06, 2009 7:51 PM

 To: lightning-list(at)matronics.com

 Subject: Re: more prop test info  

  

     

Buz  

    

I put  the 62FK60 on today.  Don't know what to think just yet.  Testing was done at 3,000 ft, 85 degrees and indicated only  

    

new prop-----------  

    

RPM                Fuel burn             Speed mph  

    

2850                 8.1                      152  

    

2750                 6.6                      146  

    

2650                 5.7                      140  

    

WOT 3,000 rpm, static 2560 rpm at WOT the EGT was 1450 degrees  

    

   

    

composite ground adjustable (old prop)  

    

2850                 6.1                      145  

    

2650                 5.1                      137  

    

WOT 3200 RPM  

    

   

    

I reached the 150 mph point but lost 2 gal per hr.  Short story long--- what are you running for jetting and I am thinking this may be an altitude prop--not used for skud running?  Nick or Buz, what jetting is needed?  

    

Thanks for any advise  

    

   

    

Dave McC  

  [quote]    

---

N1BZRich(at)aol.com
Guest

Posted: Fri Aug 07, 2009 4:28 pm Post subject: more prop test info

In a message dated 8/6/2009 8:26:01 P.M. Eastern Daylight Time,  corky(at)hbci.com writes:

  	  Quote: 	
		     I put  the 62FK60 on today.  Don't know what to think just    yet.  Testing was done at 3,000 ft, 85 degrees and indicated    only

   new prop-----------

   RPM                   Fuel    burn                Speed mph

   2850                    8.1                         152

   2750                    6.6                      146

   2650                    5.7                         140

   WOT 3,000 rpm, static 2560 rpm at WOT the EGT was 1450 degrees

    

   composite ground adjustable (old prop)

   2850                    6.1                         145

   2650                    5.1                         137

   WOT 3200 RPM

    

   I reached the 150 mph point but lost 2 gal per hr.  Short story    long--- what are you running for jetting and I am thinking this may be an    altitude prop--not used for skud running?  Nick or Buz, what jetting is    needed?

   Thanks for any advise

    

   Dave McC

	


 

 Dave,

     Finally got a chance to go for a short hop this  afternoon delivering a part to Linda.  First flight since I got back from  Oshkosh.  I tired to duplicate your flight conditions so flew at 3,000 feet  (DA was almost 4500') and OAT was 83 degrees which was close to your 85  degrees.  With the auto pilot on and 2850 rpm set, my  indicated airspeed was 152 to 153 mph and the true airspeed was 163 to  164 mph.  Fuel flow was 5.3 gallons per  hour.  I then pushed the power all the way in and WOT  resulted in 3250 rpm with an indicated airspeed of 177 to 178  mph and true airspeed of 188 to 190 mph.  Fuel flow at that high  rpm and low altitude was 11.1 gph or so.  

     As Lynn mentioned be sure to provide some good EGT  readings to Nick so he can recommend jetting for you.  Also, comparing  speeds is more accurate using true airspeeds and flying at the same density  altitude, but maybe you don't have that capability.  Overall, you are  getting great results, particularly if you have not made the mods that I  have.  But based on your WOT of only 3,000 rpm with your new  prop, and assuming your have a solid lifter engine with the valves set  good, only getting 3,000 rpm would tend to tell me you have a draggier  airframe for the engine to pull around.  What color is your airplane?   You may have a high drag paint scheme and colors.  

 Blue Skies,

 Buz

 

  [quote][b]

davemcc

Joined: 28 Feb 2007
Posts: 74

Posted: Sat Aug 08, 2009 2:49 pm Post subject: more prop test info

Bob

  

 19.5 degrees (at) 9 inches in from  tip

  

 Dave

 [quote]   ---

davemcc

Joined: 28 Feb 2007
Posts: 74

Posted: Sat Aug 08, 2009 4:40 pm Post subject: more prop test info

Buz

 Today was prop day, I tried 3 different ones.  Learned a couple of  things that may be helpful.

 Had a vibration  till I removed my fiberglass spinner, yes it was  true, but not balanced. Took it home and floated it in the sink with some water  also  in the center. Sure enough it floated like the titanic, I added  stick on lead weights to the light side to make it float level.   my  vibration was gone. Did one flight and weights stayed in place.

 another thing is auto pilot, you mounted yours forward as I did, this means  the auto pilot controls through your bell crank, I found my bushing was a "cut"  off tube that I replaced and removed any play.. My auto pilot now instead of  always searching for altitude within 50 ft and progressing, now will only search  20 then correct back to hold.

 Got the composite prop back on, not sure if the FK prop is for my  Esqual.  Someone may get a good deal on it for a Lightning, just not  sure.

 ????????????????

 Dave

 [quote]   ---

checkpoint2(at)comcast.ne
Guest

Posted: Sun Aug 09, 2009 9:47 am Post subject: more prop test info

Thanks 19.5 good info Bob Haas.  

         

  

From: owner-lightning-list-server(at)matronics.com [mailto:owner-lightning-list-server(at)matronics.com] On Behalf Of Dave

 Sent: Saturday, August 08, 2009 6:37 PM

 To: lightning-list(at)matronics.com

 Subject: Re: more prop test info  

  

     

Bob  

    

   

    

19.5 degrees (at) 9 inches in from tip  

    

   

    

Dave  

  [quote]    

---

info(at)flylightning.net
Guest

Posted: Mon Aug 10, 2009 5:35 am Post subject: more prop test info

Dave,  

   

Rejetting of the carb is almost always needed with a prop change, this certainly explains the fuel flow numbers. To get the jetting correct for that prop you will need, EGTs at WOT climp at say 100mph. and cruise EGTs at 2850RPM at say 5000 feet, let me know those numbers to get in the right direction.  

   

nick  

         

  

From: owner-lightning-list-server(at)matronics.com [mailto:owner-lightning-list-server(at)matronics.com] On Behalf Of Dave

 Sent: Thursday, August 06, 2009 6:51 PM

 To: lightning-list(at)matronics.com

 Subject: Re: more prop test info  

  

     

Buz  

    

I put  the 62FK60 on today.  Don't know what to think just yet.  Testing was done at 3,000 ft, 85 degrees and indicated only  

    

new prop-----------  

    

RPM                Fuel burn             Speed mph  

    

2850                 8.1                      152  

    

2750                 6.6                      146  

    

2650                 5.7                      140  

    

WOT 3,000 rpm, static 2560 rpm at WOT the EGT was 1450 degrees  

    

   

    

composite ground adjustable (old prop)  

    

2850                 6.1                      145  

    

2650                 5.1                      137  

    

WOT 3200 RPM  

    

   

    

I reached the 150 mph point but lost 2 gal per hr.  Short story long--- what are you running for jetting and I am thinking this may be an altitude prop--not used for skud running?  Nick or Buz, what jetting is needed?  

    

Thanks for any advise  

    

   

    

Dave McC  

  [quote]    

---

davemcc

Joined: 28 Feb 2007
Posts: 74

Posted: Mon Aug 10, 2009 7:52 am Post subject: more prop test info

Hi Nick

 I changed the main and needle jets right away. The  exhaust is at 1280 at climb which may be a bit low and also at 3,000 ft. at 2800  rpm..  I was thinking, if I got Buz's static rpm this would tell me if my  problem is in the engine or drag in the Esqual.  MY static was 2560 rpm.  valves set 12 hrs ago, compression is great, gaps set.  BUZ--

 THANKS,,  DAVE

 [quote]   ---

info(at)flylightning.net
Guest

Posted: Mon Aug 10, 2009 8:41 am Post subject: more prop test info

Dave,  

   

The static is stationary correct? What is it after 3-5 seconds of Takeoff roll, what does is settle too after accelerating down the runway?  

   

Nick  

         

  

From: owner-lightning-list-server(at)matronics.com [mailto:owner-lightning-list-server(at)matronics.com] On Behalf Of Dave

 Sent: Monday, August 10, 2009 10:45 AM

 To: lightning-list(at)matronics.com

 Subject: Re: more prop test info  

  

     

Hi Nick  

    

I changed the main and needle jets right away. The exhaust is at 1280 at climb which may be a bit low and also at 3,000 ft. at 2800 rpm..  I was thinking, if I got Buz's static rpm this would tell me if my problem is in the engine or drag in the Esqual.  MY static was 2560 rpm. valves set 12 hrs ago, compression is great, gaps set.  BUZ--  

    

THANKS,,  DAVE  

  [quote]    

---

N1BZRich(at)aol.com
Guest

Posted: Mon Aug 10, 2009 7:57 pm Post subject: more prop test info

In a message dated 8/10/2009 11:52:46 A.M. Eastern Daylight Time,  corky(at)hbci.com writes:

  	  Quote: 	
		  MY static was 2560 rpm. valves set 12 hrs ago, compression    is great, gaps set.  BUZ-- 	


 

 Dave,

     I have never seen the need to do a WOT static run  up, but rather look for the rpm on takeoff roll and perhaps more importantly,  the rpm when climbing out.  For example, my rpm when climbing out at 100  mph indicated is 2760 to 2780.  That is pretty near the power curve for the  3300.  When near max gross (which is 1320 for N31BZ) I have never seen  a take off roll longer than 700 to 800 feet even when at high density altitude  and high temperatures.  For example the temp today when I started takeoff  roll was 96 degrees.  My gross weight was about 1200 pounds and my take off  roll was right at 600 feet.  Yes, I am pretty near sea level but DA was  over 2000'.  Hope all this helps.  

     One other thought - of all the Sensenich ground  adjustable carbon fiber props I have tried, I have never found one to be as  smooth running at a wooded Sensenich.  I have even weighed the individual  blades to make sure they were the same weight.  Also, I always set the  pitch by using a prop protractor on each blade instead of the index on the  hub.  That seemed to make them run a little smoother, but still never as  smooth as their wooded props.  The other thing about the ground adjustable,  for some reason, even when set at exactly the same pitch as a wooded ZK, they  have never been as fast at the higher rpms, and that has been most noticeable  when above the 150 mph tas speed range.  Not sure what was going on, but  the wooded prop would always be as much as 8 mph faster at the same rpm.   And at WOT the carbon fiber prop would never turn up as high an rpm.   Remember they were both the same pitch, same diameter and same ZK blade  profile.  Of course the prop I am running now (and the one you are  currently testing) is a FK blade profile.  The main difference as I  understand it is the FK is a blended profile with slightly different pitches at  the tip, the mid blade and near the hub.  Tip is different for noise, mid  blade for pull, and near the hub for more cooling air into the intakes.   Seems like a great idea to me.  

 Buz

     

  

 

  [quote][b]

dashvii(at)hotmail.com
Guest

Posted: Mon Aug 10, 2009 8:21 pm Post subject: more prop test info

We've discussed similar topics to this a few times before C but when I flew the Lightning C I had the same experiences.  Never could get as high RPM at WOT with the ground adjustable.  My thoughts are that you have a couple of different things that are readily identifiable differences between the props.  (and the only two that I can think of off the top of my head) First is the mass of the entire unit C hub and all.  I think that cuts down on the RPM at WOT.  The other is your medium.  Wood tends to flex more C especially at the tips than the carbon fiber.  Props are definitely not my specialty though.  We were always taught in school that prop design was about 1/4 aerodynamics C 1/4 pure luck C 1/4 theory C and 1/4 black magic.  Not only is there a difference in pitch at various stations along the blade C you'll notice a difference in a lot of the newer designs in having raked tips.  This so called scimitar blade helps with noise as well as keeping the blade more effective at higher tip speeds.  Always interested in hearing prop info test data.  Keep it coming folks.  Brian W.

From: N1BZRich(at)aol.com

Date: Mon C 10 Aug 2009 23:41:29 -0400

Subject: Re: more prop test info

To: lightning-list(at)matronics.com

        In a message dated 8/10/2009 11:52:46 A.M. Eastern Daylight Time C  corky(at)hbci.com writes:

  	  Quote: 	
		  MY static was 2560 rpm. valves set 12 hrs ago C compression    is great C gaps set.  BUZ-- 	

 Dave C

     I have never seen the need to do a WOT static run  up C but rather look for the rpm on takeoff roll and perhaps more importantly C  the rpm when climbing out.  For example C my rpm when climbing out at 100  mph indicated is 2760 to 2780.  That is pretty near the power curve for the  3300.  When near max gross (which is 1320 for N31BZ) I have never seen  a take off roll longer than 700 to 800 feet even when at high density altitude  and high temperatures.  For example the temp today when I started takeoff  roll was 96 degrees.  My gross weight was about 1200 pounds and my take off  roll was right at 600 feet.  Yes C I am pretty near sea level but DA was  over 2000'.  Hope all this helps.  

     One other thought - of all the Sensenich ground  adjustable carbon fiber props I have tried C I have never found one to be as  smooth running at a wooded Sensenich.  I have even weighed the individual  blades to make sure they were the same weight.  Also C I always set the  pitch by using a prop protractor on each blade instead of the index on the  hub.  That seemed to make them run a little smoother C but still never as  smooth as their wooded props.  The other thing about the ground adjustable C  for some reason C even when set at exactly the same pitch as a wooded ZK C they  have never been as fast at the higher rpms C and that has been most noticeable  when above the 150 mph tas speed range.  Not sure what was going on C but  the wooded prop would always be as much as 8 mph faster at the same rpm.   And at WOT the carbon fiber prop would never turn up as high an rpm.   Remember they were both the same pitch C same diameter and same ZK blade  profile.  Of course the prop I am running now (and the one you are  currently testing) is a FK blade profile.  The main difference as I  understand it is the FK is a blended profile with slightly different pitches at  the tip C the mid blade and near the hub.  Tip is different for noise C mid  blade for pull C and near the hub for more cooling air into the intakes.   Seems like a great idea to me.  

 Buz

   	  Quote: 	

st">http://www.matronics.com/Navigator?Lightning-List

onics.com

ww.matronics.com/contribution

Get free photo software from Windows Live Click here.

Clive J

Joined: 03 Nov 2007
Posts: 340
Location: UK

Posted: Tue Aug 11, 2009 12:07 am Post subject: more prop test info

The other bit which hasn't been mentioned is flex of the blade which

creates an effective pitch change. 

This could be even more effective (or not) with a carbon prop. If you've

ever flown alongside a carbon prop'd plane you can see the bend in the

blades, coned forward. 

Manufacturers try to harness this flex/twist effect when the prop is

loaded to give an optimum pitch at different speeds and loads.

The Sens I have on my Jabiru doesn't have a covering, they told me if I

have the covering the prop needs to be 2" coarser pitch as the covering

stiffens it up and dynamically the effective pitch will change (be

finer).



Part of the 1/4 of black magic I suppose.



Either way Dave's plane seems to be banging along nicely!



Regards, Clive

--

davemcc

Joined: 28 Feb 2007
Posts: 74

Posted: Thu Aug 13, 2009 3:23 pm Post subject: more prop test info

Buz

  

 Would you be kind enough to do me a favor, Charley at Sensensich is  thinking of switching out props for a 58. Before I do that would you please  measure yours "pitch in degrees every 6 inches from tip to see if we both have  same cut, or easier, just send me your prop and I'll send you mine-just   kidding.

    I doo have all the mods as you do so Nick and I are  stumped.

  

 Dave

 [quote]   ---

N1BZRich(at)AOL.COM
Guest

Posted: Thu Aug 13, 2009 4:17 pm Post subject: more prop test info

Dave,

     I am on another trip (this time in NC on other  business) and it will be several days or more before I get home and can get to  that.  But will be happy to do so.  I will try to get the airplane as  level as possible, then will start by measuring the top of the engine to see how  level that is.  Then measurements will be based on the prop  being  horizontal.  Will that work?  

 Buz

 

  [quote][b]

davemcc

Joined: 28 Feb 2007
Posts: 74

Posted: Fri Aug 14, 2009 3:14 am Post subject: more prop test info

Buz

 perfect, I'll do mine every 6 inches and get it to you, it may be  interesting

  

 Thanks  Dave

 [quote]   ---

davemcc

Joined: 28 Feb 2007
Posts: 74

Posted: Fri Aug 14, 2009 12:11 pm Post subject: more prop test info

Buz

  

 Here is what I came up with

 prop hub at zero degrees

            Blade  1                                         Blade 2

  6"  in from tip  21     degrees   ----     21.25    degrees

 12" in from tip  26     degrees   ----     26         degrees

 18" in from tip  30.5  degrees   ----      31        degrees

 it is hard to get an accurate measurement at 18" because of the  contour

  

 thanks Dave

 [quote]   ---

N1BZRich(at)AOL.COM
Guest

Posted: Mon Aug 17, 2009 12:43 pm Post subject: more prop test info

In a message dated 8/14/2009 4:12:18 P.M. Eastern Daylight Time,  corky(at)hbci.com writes:

  	  Quote: 	
		     Buz

    

   Here is what I came up with

   prop hub at zero degrees

              Blade    1                                           Blade 2

    6"  in from tip  21       degrees   ----     21.25      degrees

   12" in from tip  26       degrees   ----     26           degrees

   18" in from tip  30.5    degrees   ----        31        degrees

   it is hard to get an accurate measurement at 18" because of the    contour

    

   thanks Dave

	


 

 Dave,

     I came up with basically the same numbers.  After  removing the top cowling and making sure the top of the engine was level by  shimming under the wheels, I then leveled the prop and took the  measurements.  Six inches in from the tips measures 21 degrees, 12"  in measures 26.5 degrees, and 18 inches in measures 30 inches for both  blades - essentially the same measurements you got.  

     If you are sure of the accuracy of your airspeed  system and tach, then something on you airframe must be slightly higher drag  than on mine.  So are you sure about your instrumentation?

     If so, then starting at the front, here are some  airframe areas to look at that many people miss:

 -How tight does the back of your spinner fit to the from of your  cowl?  Anything over about 1/4 inch is probably starting to get too  wide.  Mine is more like 1/8 inch.  

 -Engine cooling drag can be quite high.  Don't know how you have yours  set up, but if you look at how the prototype Lightning was set up, that is  pretty much the way 31BZ is set up.  Nick pretty much did the same to  the prototype that we had done on 31BZ.

 -Next, the canopy is pretty flexable and tends to spread out along the  canopy rails the faster you go.  This produces a relatively high drag area  and gets worse the faster you go.  It is caused by both airflow around the  canopy and airflow into the cockpit if you have the cockpit vents  open.  So two fixes may be required.  First, a fix to  vent the cockpit air pressure and another to keep the canopy from flexing out in  flight.   Nick fixed this on the Lightning by including the pins on  the early ones and then tabs on the later ones that hold the canopy rails  in.  I have modified my airplane with similar tabs.  Makes a big  difference in noise and drag.  If you are hearing airflow noise, you are  hearing drag. 

 -Fit of the gear leg fairings are an obvious area to make sure you have  good fit.  Mine fit tight up against the fuselage (with rubber moldings)  and tight against the pants with basically no gaps.  Also make sure they  are streamlined with the fuselage.  (you will have induced yaw if they are  not)  Wheel pant fit is also important.  Do your inboard axles  stick out?  Mine do not - there is a fairing on each one to cover  that.

 -I have reflexed my flaps and ailerons up slightly.  The  difference is noticeable, particularly at the speeds I cruise  at.  

 -Lastly, on the color spectrum, white and silver are the fastest  colors, while red, dark blue, and black are the most maneuverable.   Also, keep your paint scheme to mostly straight lines along the flight path of  the airplane for the least drag.  Curvey lines produce drag.

 -Obviously a slight bit of "tong in cheek" about that last point, but the  others are some things you might want to look at.

 Blue Skies (the high drag kind)

 Buz

 

  [quote][b]

mark(at)flylightning.net
Guest

Posted: Tue Aug 18, 2009 5:35 am Post subject: more prop test info

Checkered tails also add a couple of knots.  At least that's what I'm hoping for with my Zenith. I need all the help I can  get!

  

 Mark

 [quote]   --

davemcc

Joined: 28 Feb 2007
Posts: 74

Posted: Tue Aug 18, 2009 4:40 pm Post subject: more prop test info

Buz

 Thanks so much. 

 A couple of points, I have a muffler on mine and you have pipes, it may be  cutting down on airflow. I might throw my pipes back on.

       I had my BRS staps fiberglassed on the  exterior because I was woried how the straps would find their way AROUND me  to the spar if mounted inside. This caused about 1.5 inch rise on the  fuslage on both sides.  I can see where this may slow her down.  I'll  quit bugging you and play with it for awhile

 Again-thankyou

 Dave

 [quote]   ---

Display posts from previous:

	Matronics Email Lists Forum Index -> Lightning-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum