VansAirForceForums  
Home > VansAirForceForums

-POSTING RULES
-Advertise in here!
- Today's Posts | Insert Pics

Keep VAF Going
Donate methods

Point your
camera app here
to donate fast.

  #81  
Old 06-25-2016, 10:43 AM
John-G John-G is offline
 
Join Date: Jan 2012
Location: Northeast Ohio
Posts: 759
Default Setting initial pitch prior to engine start

Installed the Sensenich propeller yesterday and used the Sensenich pitch tool #3 to rough adjust the rough pitch as suggested in 47-03 step 7.

Later, the steps on 47-07 were followed. A digital level was zeroed on the canopy rail per the instructions, then attached onto the TOOL-00002 which was hung on the leveled propeller blade at the prescribed location. In order to achieve the stated 71.4 degrees of pitch, the propeller blades needed to be moved quite a bit ? should have written it down, but think the pitch was somewhere in the mid 60?s.

My question is directed to those builders who first set the propeller?s rough pitch using the #3 Sensenich pitch tool as per step 7 on 47-03 ... then later adjusted to 71.4 degrees following the new procedure on page 47-07 using a digital level and the TOOL-00002 to set the pitch ? did you too discover the Sensenich #3 pitch tool is not even close to 71.4 degrees? Just wondering if I?ve done (or am doing) something wrong.
Happy Building,
__________________
John
http://www.dogaviation.com/

RV-12 Wings, Empennage, Fuselage, Finishing, Avionics and Powerplant kits all completed
Now Flying!!

Donation paid until September 2021
Reply With Quote
  #82  
Old 06-25-2016, 08:13 PM
Phantom30's Avatar
Phantom30 Phantom30 is offline
 
Join Date: Jul 2009
Location: Coeur d'Alene, ID/Casa Grande, AZ
Posts: 654
Default

Quote:
Originally Posted by John-G View Post
Installed the Sensenich propeller yesterday and used the Sensenich pitch tool #3 to rough adjust the rough pitch as suggested in 47-03 step 7.

Later, the steps on 47-07 were followed. A digital level was zeroed on the canopy rail per the instructions, then attached onto the TOOL-00002 which was hung on the leveled propeller blade at the prescribed location. In order to achieve the stated 71.4 degrees of pitch, the propeller blades needed to be moved quite a bit … should have written it down, but think the pitch was somewhere in the mid 60’s.

My question is directed to those builders who first set the propeller’s rough pitch using the #3 Sensenich pitch tool as per step 7 on 47-03 ... then later adjusted to 71.4 degrees following the new procedure on page 47-07 using a digital level and the TOOL-00002 to set the pitch … did you too discover the Sensenich #3 pitch tool is not even close to 71.4 degrees? Just wondering if I’ve done (or am doing) something wrong.
Happy Building,

Not sure how much I had to move mine, but both required more than a little. I managed to get both blades within 1/2 degree or less of each other. Plane flies per spec....and really smooth. Loving it!!
__________________
Ric Dickison
307 (CAB) Phantom
Search and Destroy (Can
Tho RVN)
Distinguished Flying Cross Society Member
CH-47 & UH-1H "Driver"
Rotax 9 Series Service IRMT

RV-12 Kit#729 "N312RD" is now a full functioning fun machine!! Thanks Van for fulfilling my dream😎
2018 Dues Paid
Reply With Quote
  #83  
Old 06-26-2016, 12:54 AM
Sink Sink is offline
Banned
 
Join Date: Apr 2015
Location: Altha, FL.
Posts: 114
Default

After talking to the head Phd researcher a few years back from Sensenich and he said they thought the pins would work well, but not as good as they hoped, but looked good on paper. They set their props by hand without the pins. The pins only get you in the ballpark and once removed the blades should be fine tuned individually by hand. You should be able to get a 3 blade prop within
.1 degree between all blades without much trouble. Leveling the plane isn't necessary because what ever you do to one blade will be the same to the other. Knowing an exact pitch number isn't important. Just set a static for around 4900-4950 rpm and then it needs to be flown to get the final pitch setting. 2 blades and 3 blades will have different settings and some times different static rpms. Bottom line is the final WOT rpm in flat and level flight.
For ground adjustable props that seems to be around 5600-5650.

Altitude considerations count:

The pitch for one owner at sea level that never goes over 2K ft. will be different than someone who lives in Mammoth, CA and flies all the time at 10-13K ft. Set your prop for your personal average altitude. This is not a one size fits all.
Reply With Quote
  #84  
Old 06-26-2016, 07:19 AM
John-G John-G is offline
 
Join Date: Jan 2012
Location: Northeast Ohio
Posts: 759
Default

Thanks Ric ... after hearing you too needed to move the blades quite a bit after using the Sensenich tool I feel much better now.

Sink thanks for the input. I understand the ultimate goal is based on the numbers during engine run as you stated ... and to get there, each builder has variables unique to the region the aircraft is based. I was just concerned because the pitch pin was not even close and I was expecting the fine tuning to be within a degree or so.
__________________
John
http://www.dogaviation.com/

RV-12 Wings, Empennage, Fuselage, Finishing, Avionics and Powerplant kits all completed
Now Flying!!

Donation paid until September 2021
Reply With Quote
  #85  
Old 10-27-2021, 01:29 AM
constantin_w constantin_w is offline
 
Join Date: Jul 2021
Location: Hannover
Posts: 5
Default

Hi guys, I know this post is dead old. However, I recently bought a flying RV-12 from 2013 (912 ULS) which unfortunately has various unpleasant surprises hidden under the canopy...
Working on the reduction of these issues, one topic is also propeller pitch. I read through the whole topic here and came along two different numbers which seem to contradict. When the aircraft is on the ground and we push the throttle all in (WOT), where should the rpm end up? I read 4950 and 5600 rpm (quite a difference). I am from northern Germany with almost no elevation of the field (300ft) and our flight altitude is most likely 5000ft and less in most cases. Which rpm is recommended?
Thanks for your help!
Reply With Quote
  #86  
Old 10-27-2021, 02:59 AM
Piper J3's Avatar
Piper J3 Piper J3 is offline
 
Join Date: Nov 2014
Location: Hinckley, Ohio
Posts: 2,566
Default

Set prop pitch to attain ~ 5150 RPM WOT during initial climb out. This is the sweet spot that will provide 900ish FPM climb and Vanís spec for 114 KTAS at 5500 RPM. With this pitch, throttle position will be pulled out about 1Ē for 5500 RPM and will allow engine to go over redline if throttle is advance to WOT in cruise flight.
__________________
-
Jim Stricker - EAA #499867
PPL/ASEL 1970 - Sport Pilot since 2007
80 hrs Flying Aeronca Chief 11AC N86203
1130 hrs Flying 46 Piper J-3 Cub N6841H
Bought Flying RV-12 #120058 Oct 2015 with 48TT - Hobbs now 750

LSRM-A Certificate 2016 for RV-12 N633CM
Special Thanks... EJ Trucks - USN Crew Chief A-4 Skyhawk
MJ Stricker (Father - CFI) - USAAF 1st Lt. Captain B-17H
Reply With Quote
  #87  
Old 10-27-2021, 01:25 PM
NinerBikes NinerBikes is offline
 
Join Date: Dec 2018
Location: Granada Hills
Posts: 1,193
Default

5150 rpm at 75 kts (Vy) climbout speed, on take off.

You'll see more rpms, maybe 5200-5220, if climbing out at 85 kts.

After engine was warmed up, I seem to recall seeing about 4980-5000 rpm static. Might want to tie the rear eyelet off to a trailer hitch on a heavier truck or something before trying that, if your brake pads aren't bedded in fully yet to the rotors, like on a new plane.
__________________
Donated
RV-12, KWHP based

"Time to Spare, go by Air."

Last edited by NinerBikes : 10-27-2021 at 10:47 PM.
Reply With Quote
  #88  
Old 10-27-2021, 03:48 PM
funflying funflying is offline
 
Join Date: Oct 2006
Location: arvada, co
Posts: 502
Default

There are a number of articles about setting the prop pitch on a Rotax 912ULS. The static - on the ground WOT - to see if I was close to a flight setting pitch was 4900-5100 RPM. If your degrees of pitch gets this RPM on the ground then moved to the flight test and note the RPMs like others mentioned in prior posts.
The other bench mark I use is a pitch that while in level cruise, at WOT, will show 5650 RPM. Then a very small increase or decrease of pitch to try and achieve the 5650 RPM.
Rotax Owner has some of these articles.
__________________
Patrick Claar
Arvada, CO BJC
RV12, #401, Flying 2013, N612PC
RV6, 1996-2010 sold
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 08:47 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.