[NSRCA-discussion] APC 18.1 x 10W props / isn't progress great

Thu Nov 16 05:13:14 AKST 2006

I know that this is a little off topic, but all this talk of swinging oars has got me a little nostalgic. I used to fly a PA-2 with a YS60FR 2-stroke and an APC 11x11 prop. It was very quiet with what I thought was great performance. 

  I never in my wildest dreams would have imagined that we would be swinging props that were almost twice the diameter with nearly the same pitch. Progress is awesome!!!!

  Now back to your regularly scheduled programming.

  Anthony

Mike Hester <kerlock at comcast.net> wrote:
      That's true, it's just a feel thing. I agree with Mike's assessment.

  I'm using the 18.1x10 regular and Jim Ivey is using the 18.1x10w clipped. They both work really well. Mine tachs right around 8100, Jim's is really close to that number as well.

  The differences in the 2 as I can see, just an impression: The 18.1x10 that I'm using has a really wide speed envelope. Good slow down lines but it will turn into a rocket at full power. It does load the engine down a bit, but I'm running it a little rich.

  The 18.1x10W clipped that Jim is using has really good down lines, good top end, but at cruise speed it's turning more RPMs. As a result, he doesn't have to move the stick too much transitioning from level to an upline. it has pretty good flat torque.

  I'd say it this way: If your style is slower, try the clipped 10W. if you like to move along a little faster during normal flight, use the regular 10. 

  That's just my impressions right now. Note that I haven't tested these props on really hot, humid days, so I can't say for certain if it's too much load or not. Yet.

  -Mike

  PS it's also important to note that these props are too big for a normal TT 3" 120 cut spinner. Close, but you have to open up the cut outs slightly. At least I had to....
    ----- Original Message ----- 
  From: mike mueller 
  To: NSRCA Mailing List 
  Sent: Wednesday, November 15, 2006 1:04 PM
  Subject: Re: [NSRCA-discussion] APC 18.1 x 10W props

 In my case its just a touchy feely thing. I tend to base most things on it. Mike

Bob Richards <bob at toprudder.com> wrote:     I'm curious about how one comes up with the best prop selection. In my case, it has always been a very subjective thing to determine the in-flight performance.

  Has anyone used any of the dataloggers to measure airspeed on up/down/level lines? IMHO, that would be one way to remove some of the subjectivity of in-flight performance. I think one of my christmas wish-list items is the Eagle Tree system.

  Bob R.

mike mueller <mups1953 at yahoo.com> wrote:
   From my experience this is the best prop I have tried to date. I have mine on a YS160/Genesis. I was using Biela 3 bladed props,APC 4 bladed props and the 18x10.1 regular APC and this gives the best performance so far. Mike Mueller 

"Dr. Mike Harrison" <drmikedds at sbcglobal.net> wrote:       @font-face {   font-family: Palatino Linotype;  }  @font-face {   font-family: Comic Sans MS;  }  @page Section1 {size: 612.0pt 792.0pt; margin: 36.0pt 77.95pt 36.0pt 77.95pt; }  st1\:* {   BEHAVIOR: url(#default#ieooui)  }  P.MsoNormal {   FONT-SIZE: 12pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Palatino Linotype"  }  LI.MsoNormal {   FONT-SIZE: 12pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Palatino Linotype"  }  DIV.MsoNormal {   FONT-SIZE: 12pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Palatino   Linotype"  }  A:link {   COLOR: blue; TEXT-DECORATION: underline  }  SPAN.MsoHyperlink {   COLOR: blue; TEXT-DECORATION: underline  }  A:visited {   COLOR: purple; TEXT-DECORATION: underline  }  SPAN.MsoHyperlinkFollowed {   COLOR: purple; TEXT-DECORATION: underline  }  P.MsoPlainText {   FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Courier New"  }  LI.MsoPlainText {   FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Courier
 New"  }  DIV.MsoPlainText {   FONT-SIZE: 10pt; MARGIN: 0cm 0cm 0pt; FONT-FAMILY: "Courier New"  }  P {   FONT-SIZE: 12pt; MARGIN-LEFT: 0cm; MARGIN-RIGHT: 0cm; FONT-FAMILY: "Times New Roman"; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto  }  SPAN.EmailStyle17 {   FONT-WEIGHT: normal; COLOR: blue; FONT-STYLE: normal; FONT-FAMILY: "Comic Sans MS"; TEXT-DECORATION: none; mso-style-type: personal  }  SPAN.EmailStyle18 {   COLOR: navy; FONT-FAMILY: Arial; mso-style-type: personal  }  SPAN.EmailStyle20 {   COLOR: navy; FONT-FAMILY: Arial; mso-style-type: personal  }  DIV.Section1 {   page: Section1  }      Peter,
  Hi,
  I am Mike Harrison, I worked with APC to develop these props.  Let me tell you the goal of the prop design.  It is to fly at a moderate to slow constant speed under the noise limit but with good pulling performance.  Therefore, regarding the rpm, the 8000 is about ideal for that prop, turn it much more and you will be above the noise limit.  

  I find it interesting that you determine whether a prop is adequate by first tacking it.  I would think you would fly it first to see if it was adequate.  I would encourage you to do that first.  The OS 140 turns it about the same and it flies very well. 

  The whole purpose was to develop a prop that would fly at a deliberate pace at about 150 meters to compete with the electrics.  

  There is also an 18.5x9.5 which I fly and it turns about 7500 rpm.  I like it better than the 18.1x10.  I am working on a 19x9 at the moment.

  Good luck
  Mike
    From: Peter Pennisi 
  To: 'NSRCA Mailing List' 
  Sent: Tuesday, November 14, 2006 5:48 PM
  Subject: [NSRCA-discussion] APC 18.1 x 10W props

  I recently purchased some 18.1 x 10W APC props for my DZ160. Apparently there appears to be another version 18.1 x 10.1.

  Could someone please tell me the difference between both?

  I tried a quick ground run on this prop (stock) this morning but could barely get 8000 RPM from the engine. I will take advice from a member on this list and lop 1/4inch of each blade. What RPM readings are people getting who are using either of these props on a YS DZ160 engine?

  Regards,

  Peter 

---------------------------------

_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion

---------------------------------
  Sponsored Link

Don't quit your job - take classes online and earn your degree in 1 year. Start Today_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion

_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion

---------------------------------
  Sponsored Link

Mortgage rates near 39yr lows. $310,000 Mortgage for $999/mo - Calculate new house payment     
---------------------------------

_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion_______________________________________________
NSRCA-discussion mailing list
NSRCA-discussion at lists.nsrca.org
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20061116/99905d64/attachment.html 