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  #1  
Old 01-02-2011, 06:47 PM
plehrke's Avatar
plehrke plehrke is offline
 
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Default Do you do partial power take-offs?

I was always taught to use full power until you get to a safe altitude (typically pattern altitude). When I started to fly my RV-6A four years ago I wondered whether I really needed full power on every take-off, after all I am in the air in 500 ft, but I still use full power. Now in the cold of STL this winter I have been again thinking if I ought to use less then full power as the plane is even more peppy. Just wondering how many people use less then full throttle for take-off.
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Old 01-02-2011, 07:02 PM
BlndRvtr BlndRvtr is offline
 
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Why are you considering reduced power take-offs? Are you running an engine with full power time limits? Do you perceive a benefit from reduced power take-offs? Once we know your goals then we can better address your question.

George
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Old 01-02-2011, 07:02 PM
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hydroguy2 hydroguy2 is offline
 
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I use full power always.

disclaimer: I've only got 7.2hrs on her and I'm breaking in my engine.

Soon I will be using full power until I reach 1000' then pull back to 2500.
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  #4  
Old 01-02-2011, 07:34 PM
jws_39 jws_39 is offline
 
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Default Full power take

The only time I don't is when I am in a formation take off. I use full power even time with a 6000ft runway just because it is more fun and impresses the locals
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  #5  
Old 01-02-2011, 07:35 PM
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Geico266 Geico266 is offline
 
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I rarely use full power. Waste of fuel.
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Old 01-02-2011, 07:49 PM
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Hens07 Hens07 is offline
 
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Always full power unless practicing high density altitude takeoffs. But then again that's in a Piper Archer and not the RV-7 I'm working on :-(
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  #7  
Old 01-02-2011, 07:56 PM
sjarrell sjarrell is offline
 
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Location: Hendersonville, NC
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Quote:
Originally Posted by plehrke View Post
I was always taught to use full power until you get to a safe altitude (typically pattern altitude). When I started to fly my RV-6A four years ago I wondered whether I really needed full power on every take-off, after all I am in the air in 500 ft, but I still use full power. Now in the cold of STL this winter I have been again thinking if I ought to use less then full power as the plane is even more peppy. Just wondering how many people use less then full throttle for take-off.
Altitude is my friend :-). Yes, full power, full rpm till 1000', then 2500rpm WOT till cruising altitude. IMHO it's safer to get up quicker, and it's certainly more fun! :-)))))).
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Old 01-02-2011, 08:02 PM
Sig600 Sig600 is offline
 
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As the old adage goes, the most worthless things to a pilot are runway behind you, altitude above you, and fuel in the truck.

Most airlines use partial power take off's 90% of the time. I'll vary how much power I use for what I fly at work based on conditions.

That said, those are multi engine a/c. If we accept that we're in a single engine a/c and remove engine out considerations, then yes for longevity you can probably lengthen the life if your engine by minimizing your use of full throttle. However if you're doing a reduced power takeoff, and cruise climb to cruise alt you're almost guaranteed to burn more gas than to use full power to altitude, where you can get back to a cruise power setting, speed and fuel burn sooner. Try testing it out some time. Do a reduced power take off and cruise climb to say 10K', and see how long it takes and how much fuel you burn. Then do it again with full power and a Vy climb to 10K. Curious to see the results if anyone tries it out.
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  #9  
Old 01-02-2011, 08:04 PM
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plehrke plehrke is offline
 
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Quote:
Originally Posted by sjarrell View Post
Altitude is my friend :-). Yes, full power, full rpm till 1000', then 2500rpm WOT till cruising altitude. IMHO it's safer to get up quicker, and it's certainly more fun! :-)))))).
I agree with the more fun and get to safe altitude faster. Of coarse everybodies situation is different (short field etc) but I fly out of an airport that is under the 1700 ft level of a Class B. Therefore I can only climb 1000 ft and then have to level off and fly 5-10 nm before I can start a slow climb until clear of the Class B.
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  #10  
Old 01-02-2011, 11:46 PM
asav8tor asav8tor is offline
 
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On many piston aircraft a slightly reduced power takeoff is potentially harmful because you do not engage the full power enriching that provides extra cooling fuel on the slow, high power pull on takeoff. A fully loaded pig 172 at sea level on a hot day, fixed pitch, way over square limping into the air with little cooling air and a throttle pulled back 1/4" with CHTs climbing through 400f is a perfect example of why it is often taught not to do partial power takeoffs in a piston acft........

...... However, this is NOT the senario with most RVs; Most are so nimble they can takeoff with a very significant power reduction and not create CHT cooling issues as described above. Is this easier on the engine? Yes. Will the engine last longer? Perhaps not. Most RVs might rust out before they wear out. Will this save gas? Depends. One thing I have noticed using a lot of all around reduced power ops is the oil gets dark faster. I'm not sure but perhaps extensive use of reduced power (all around) is making the oil get darker faster because the rings are allowing more blow by with less pressure? Any gurus on this one?
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