Mailing List flyrotary@lancaironline.net Message #4535
From: Russell Duffy <13brv3@bellsouth.net>
Subject: RE: [FlyRotary] Brief flight report
Date: Sat, 29 Nov 2003 17:33:31 -0600
To: 'Rotary motors in aircraft' <flyrotary@lancaironline.net>
Message
Take off temps never got above 175 for coolant and 165 for oil.   
 
 We stayed at pattern altitude and reduced power to about 3600 or 80 kts.   On landing the temps came down to about 160 and showed the same max temps on repeated takeoffs.   
 
Congrats on the improvement.  Try to make an extended climb when you get a chance, to see how the temps hold up, particularly the oil.  I made the mistake of doing a couple of tests to only 2000 ft, and everything seemed great.  Unfortunately, my oil temp takes a while to stabilize, and it just wasn't getting to full temp in the minute that it takes to get to 2000 ft.  The water seems to react more quickly, and stabilizes in just a minute or so.   

 

The Ivo pitch was reduced by ~6” to 60” in an effort to get more RPM/ power developed without reducing pitch too much and losing thrust.  Acceleration was better and we lifted of in less than 1000ft and climbed out at 1200 fpm.  RPM never got above 4900 at WOT, but this is an improvement of ~400 rpm from the previous setting.  Should I reduce pitch more?

 

 I assume that you're using the ground adjustable IVO, not the in-flight adjustable.  If that's the case, you'll have to compromise like the rest of us.  Within reason, less pitch gives more RPM, better climb, but over-revs when attempting high speed runs.  More pitch is just the opposite.  

 

At some point, you need to decide what you want your limits to be.  What's the max RPM you are willing to run?  What cruise RPM do you want to fly at?  What maximum power are you willing to run continuously?   Do you want to optimize the prop for cruise, or climb?  Once you figure all this out, you can set the pitch for the best compromise.  In the mean time, I'd say you certainly could reduce the pitch a bit more, and go for something closer to 5500 RPM for climb.  This will be another cooling system test though, since you'll be making more power.

 

Cheers,

Rusty 

 

 

  

 

 

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