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Bill3558

FDCT vs C172

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I feel that wind isnt a big issue for SW.

There are 2 CFIs in my field that fly all the time when wind is gusting at 20 kt.

I have done a few landings when 90 degree direct cross wind was gusting at 20 kt also, it seems like landing with no wind is harder than landing with cross wind in my experience.

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4 hours ago, FlyingMonkey said:

. . . . . it sounds like your prop may be way over-pitched . . . . . would think you should be able to hit at *least* 115kt somewhere in the power curve.

x2
Time for a prop pitch adjustment.

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26 minutes ago, WmInce said:

Time for a prop pitch adjustment

Yeah, I will add that to the list at the balancing event.  Will contact FD USA and determine what the optimum pitch is.

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You can check in with FD if you want but no need to.

Check your RPM in full throttle level flight. Should be 5500-5600 RPM.

If it isn't simply move each blade about 1/4 degree in appropriate direction. You do this a blade at a time but first mark each blade about 12 inches from the tip with tape. Make sure you mark each blade the same distance. Then level each blade with a level and attach your inclinometer at the tape. You are not looking for a hard number. You just want to compare the blades to each other. When done, each blade needs to read the same on the inclinometer. 

Your prop manual should explain how to do this and lists torque values and sequence.

Roger or Tom can probably explain this better since they do it frequently whereas I check mine once a year.

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1 hour ago, sandpiper said:

Check your RPM in full throttle level flight. Should be 5500-5600 RPM.

I texted with Arian, he said the same thing essentially... it is all about the RPM's... I think I am going up there Thursday AM and we will adjust it at that time.  I can't even spell inclimatoatorometer let alone use one John... I tend to learn by watching first... meanwhile I will pull the process up on Youtube.  I hope there are vids showing what you are describing.  

 

AndyB the pic was a bit fuzzy but clearly yours is faster and the wind is not in your favor.  

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2 hours ago, Skunkworks85 said:

What is a "Sport engine mod"?

It was a design change for the fuel injected engines. The early engines lacked torque when compared to the 912ULS. 

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Ed, that Cessna must have had a 150hp motor or a cruise type propeller. Those numbers are not indicative of the one (180hp) I fly. No problem climbing to 12,500.

Sandpiper is spot on. If the prop is pitched for 5600 rpm wide Open throttle at cruise alt then you should be able to fly at least 115kts at 5400rpm.

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52 minutes ago, Duane Jefts said:

Ed, that Cessna must have had a 150hp motor or a cruise type propeller. Those numbers are not indicative of the one (180hp) I fly. No problem climbing to 12,500.

Sandpiper is spot on. If the prop is pitched for 5600 rpm wide Open throttle at cruise alt then you should be able to fly at least 115kts at 5400rpm.

160 and very high time I believe.  It was more the rate of climb then ability to continue.  My Skyhawk was 180hp and a bit faster and much better in climb.

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I am going to start a new string regarding prop pitch and speeds soon... I hope folks participate with the relevant info, including panel pics which reveals the relative wind information on the newer avionics.  I will be the first one out, I think it will be healthy for all who are interested in maximizing speeds like I am.

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13 hours ago, AGLyme said:

I texted with Arian, he said the same thing essentially... it is all about the RPM's... I think I am going up there Thursday AM and we will adjust it at that time.  I can't even spell inclimatoatorometer let alone use one John... I tend to learn by watching first... meanwhile I will pull the process up on Youtube.  I hope there are vids showing what you are describing.  

 

AndyB the pic was a bit fuzzy but clearly yours is faster and the wind is not in your favor.  

119 TAS, 115 Groundspeed, (036 heading, wind 323 @41kts, 5500' MSL), 5470 RPM, 4.7 gal/hr

If I keep the RPM slightly under 5500 so as to not go past 5500, I typically get just under 120 TAS.  At 5500, it's right at 120 TAS.

At full gross, if I set the autopilot at 500 foot/minute climb, it will easily climb to 5500 or 6500 MSL, without issues with pitch angle compromising forward visibility, or low indicated airspeed.

Andy

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16 hours ago, sandpiper said:

You can check in with FD if you want but no need to.

Check your RPM in full throttle level flight. Should be 5500-5600 RPM.

If it isn't simply move each blade about 1/4 degree in appropriate direction. You do this a blade at a time but first mark each blade about 12 inches from the tip with tape. Make sure you mark each blade the same distance. Then level each blade with a level and attach your inclinometer at the tape. You are not looking for a hard number. You just want to compare the blades to each other. When done, each blade needs to read the same on the inclinometer. 

Your prop manual should explain how to do this and lists torque values and sequence.

Roger or Tom can probably explain this better since they do it frequently whereas I check mine once a year.

 
Here's a write-up I made a couple of years ago for another member with pictures.  This procedure has worked well for me, I have done it several times.  It's based on detailed instructions I got from Roger Lee.  The idea should be the same for any ground-adjustable prop, but this is specifically for the Neuform three blade.

 

 
So here is how you do it.  It looks like a lot of steps, but each step really only takes seconds, especially once you've done it a time or two.  The procedure:
 
1) First, mark your prop spinner so that when you put it back on it will be in the same orientation.  Do do this so as not to mess up the balance.  I have a little nick on the back of my spinner that I use for this, indexed to a red Sharpie mark I put on the spinner backing plate.  
 
Once you mark this, remove the six hex head screws that hold the spinner on.  The spinner then just pulls off.  Set it aside. 
 

Inline image 2

 
2) The prop hub is now exposed, and you can see nine bolts.  Six are 13mm hub bolts, and three are 10mm blade bolts.  The 13mm bolts go all the way through the hub, and have nuts on the back (they need a wrench on both sides to loosen/tighten); the 10mm bolts are threaded into the hub and have no backing nuts.  All the bolts are secured with "Nord Lock" toothed washers.
 
Go ahead and loosen all six of the 13mm hub bolts.  You don't have to take them off or loosen them a lot -- just enough that they will turn easily by hand is enough.  You are just creating some play in the two halves of the hub.
 
Inline image 3
 
 
3)  Now you want to mark each blade, so that we are making our adjustments at the same point on each blade.  I use blue painter's tape to mark them.  Roger recommends using 8" from the tip, so  that is what I used, though I think any measure between 6" and 12" would work, as long as they are all the same.  
 
I measured from the trailing edge of the blade where it's flattest.  Put the tape perpendicular to the blade, with the outer-most edge of the tape right at 8":
 
Inline image 4
 
 
4) Now you want to level your first blade.  Both sides of the blade are curved, so you can really only level it at one point on the blade.  Luckily, we put tape on it that is the same on all blades, which also provides a convenient level point.  Just level it right in the middle of the tape.
 
NOTE:  Once the blade is level, you don't want to move it.  If you bump it or it moves slightly when tightening or loosening the blade bolts, you should re-level it before continuing.  
 
Inline image 5
 
 
5) Slide the protractor onto the blade.  Use the outer edge of the tape, and place the inside edge of the protractor against it.  This makes sure the position of the protractor is the same on all blades, and that it's perpendicular. (sorry this pic is blurry)
 
Inline image 6
 
 
6) Set the protractor to the new setting you want.  You can see in the pic below that the index mark on the top of the white dial reading zero is at a setting of slightly over 22° on the outer gray scale at the top.  That is the setting I want.  You can see the bubble in the center of the protractor is far away from level, so I'm not on the correct setting.
 
NOTE:  Once you have the protractor set for the first blade, LOCK the protractor dial in place and do NOT adjust it again.  This will ensure that all the blades have the same setting.  If you adjust the protractor between blades there is no way to know if the blades are set the same.
 
Now you loosen the two 10mm blade bolts on either side of the blade you're working on, leaving the third one alone.  Again, just loose enough to create play.  When you are loosening the bolts, you can keep the hub from turning (and requiring re-leveling) by holding one of the other blades and being gentle while loosening the 10mm bolts.  The blade you are working on will now rotate.
 
Inline image 7
 
 
7)  Now you simply level the bubble.  The blade in the pic below is now set to the correct setting, the bubble dead center.  When rotating the blade, pull *out* on the blade slightly.  That eliminates any lateral play in the blade so that when it's spinning in flight it can't move and cause slight changes in pitch.
 
Once you are happy with the bubble position, tighten one of the 10mm bolts slowly, making sure the protractor bubble stays level.  Don't tighten the bolt all the way, just snug it down.  If you still like where the bubble is, snug down the other bolt too.
Inline image 8
 
 
😎  The first blade is now done!  Simply follow that procedure for the other two blades.  When rotating the prop to do the next blade, only use a blade you have NOT adjusted yet to turn the prop.  That will avoid pulling a set blade out of the new setting.
 
9)  Once all three blades are set, it's time to torque everything back up.  Do it in this order:
 
-- Torque all six 13mm bolts to 225 inch-pounds.  So these in a star pattern like a car wheel, doing opposite pairs of bolts.  After you tighten them all go around the hub and re-check each one in sequence.
 
-- Torque all three 10mm bolts to 120 inch-pounds, going around the hub.  Go around twice so each bolt is checked twice.
 
-- Finally, put the spinner back on, taking care to align it by the mark(s) you made earlier, and make sure all six hex screws are in place and tight.  Again, go around the spinner twice to make sure.
 
10)  VERIFICATION:  In turn, level each blade.  Slide the protractor on in the same position as before.  The protractor bubble should be level on each blade after leveling.  That indicates all blades are pitched the same.  If not, you have a problem and should probably start over.
 
11)  Take the tape off the prop blades, cowl that bitch up, and go fly!   :)
 
NOTES:
 
a)  On first startup after adjusting the prop, listen and feel for any unusual vibration.  If anything unusual is detected, shut down and investigate.  
 
b)  Let the engine warm up, and before taxi run it up to 3000-4000rpm.  If there is any problem it's better to find out right in front of your hangar than when you are halfway across the airport.
 
c) On takeoff, pay attention to your rolling rpm!  Once you hit full throttle, if your RPM is below 4800rpm or above 5200rpm,  you are probably outside the efficient pitch range for your prop, and might have problems in climb or cruise.  Abort the takeoff and investigate.  Confirm the prop pitch you set is correct.  Note climb performance and compare to previous settings. 
 
d)  You can make a circuit or two of the pattern to confirm everything is working normally.  Then leave the pattern, go to normal cruise altitude.  Check speeds at 5000rpm, 5200rpm, and 5400rpm.  Compare to your previous speeds for any changes.  Then go to WOT and wait for the rpm to stabilize.  Note the final WOT number.  Make sure you keep trimming to keep the airplane as level as possible, no climb or descent.  Ideal is 5600-5700rpm.
 
e)  Enjoy your new prop settings!  
 
 

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