The 55 MPG airplane

The most important note from the article is that it is a low-wing aircraft. Clearly.

I wonder what the specifics were; I'd heard of a guy who gets incredible range on his experimental by running at 300º LOP
 
Apache123 said:
The most important note from the article is that it is a low-wing aircraft. Clearly.

I wonder what the specifics were; I'd heard of a guy who gets incredible range on his experimental by running at 300º LOP
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300 degrees below EGT or is that the CHT he is running? 100 degrees below peak EGT is about the most airplane engines will run at. I run about 50 LOP myself.
 
Apache123 said:
The most important note from the article is that it is a low-wing aircraft. Clearly.

I wonder what the specifics were; I'd heard of a guy who gets incredible range on his experimental by running at 300º LOP
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Sac Arrow said:
300 degrees below EGT or is that the CHT he is running? 100 degrees below peak EGT is about the most airplane engines will run at. I run about 50 LOP myself.
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I agree, no way an engine would run at -300F LOP. Maybe Apache misunderstood. :dunno:

In any event, it is cool that this guy is really pushing the envelope on efficiency.

A buddy of mine in a motor glider flew for 3 hours hiring only a quart of fuel. :eek: Granted , in a glider you need to stay close to the airport, but still an amazing efficiency feat.
 
What about Klaus Savier's 100mpg Vari EZ?
http://www.aopa.org/aircraft/articles/2008/081230100mpg.html

FWIW, the AOPA article states that Klaus runs 300 degrees LOP. It implies EGT although it isn't specifically stated (and engines need the kinds of precise fuel injection that allows his Continental to run an almost incomprehensible 300 degrees lean of peak).

I find it interesting that neither plane has a retractable gear. That tells me that a good, efficient design doesn't need RG, though that point has probably been clear for a long time.
 
I know I generally get 100-150F LOP in cruise without even trying in my 172, now with the finewire plugs it does very good, and I've got matched injectors too - I'll take it up and test it to see just how far LOP it goes and still make decent power.
 
Geico266 said:
A buddy of mine in a motor glider flew for 3 hours hiring only a quart of fuel. :eek: Granted , in a glider you need to stay close to the airport, but still an amazing efficiency feat.
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Oh Really?

looks like a cool plane.
 
Sac Arrow said:
300 degrees below EGT or is that the CHT he is running? 100 degrees below peak EGT is about the most airplane engines will run at. I run about 50 LOP myself.
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I don't think his airplane is most. And if he is just following what everyone else does then he would not be setting records.

Geico266 said:
I agree, no way an engine would run at -300F LOP. Maybe Apache misunderstood. :dunno:

In any event, it is cool that this guy is really pushing the envelope on efficiency.
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Why is there no way? I don't know if it was a mistake, but sometimes we need to think outside the box. He is obviously doing something different than others to get the great economy. I would like to know all the details of his mods, but i cant find them yet.

It is definitely cool that he is doing it.:thumbsup:
 
flyingmoose said:
I don't think his airplane is most. And if he is just following what everyone else does then he would not be setting records.


Why is there no way? I don't know if it was a mistake, but sometimes we need to think outside the box. He is obviously doing something different than others to get the great economy. I would like to know all the details of his mods, but i cant find them yet.

It is definitely cool that he is doing it.:thumbsup:
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Obviously he is doing something right. I would think you would start losing volumetric efficiency if you get too lean of an A/F ratio, but maybe 300 LOP on his engine hasn't reached that point, I don't know. Certainly I like what he's doing.

(EDIT: Metering power by running extremely lean on a wide open throttle is far more efficient than throttling to control power at a richer setting, even if still lean of peak.)
 
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Sac Arrow said:
Obviously he is doing something right. I would think you would start losing volumetric efficiency if you get too lean of an A/F ratio, but maybe 300 LOP on his engine hasn't reached that point, I don't know. Certainly I like what he's doing.

(EDIT: Metering power by running extremely lean on a wide open throttle is far more efficient than throttling to control power at a richer setting, even if still lean of peak.)
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If headwinds are not an issue my cross country technique in the 152 was to firewall it on takeoff and the throttle stays there until its time to descend. I'd cruise around 8000-10000 feet and lean it as much as I could without it running rough. Usually around 85kt TAS and 4 gph.

Now in a wet rental, that's another story
 
SteveR said:
What about Klaus Savier's 100mpg Vari EZ?
http://www.aopa.org/aircraft/articles/2008/081230100mpg.html

FWIW, the AOPA article states that Klaus runs 300 degrees LOP. It implies EGT although it isn't specifically stated (and engines need the kinds of precise fuel injection that allows his Continental to run an almost incomprehensible 300 degrees lean of peak).

I find it interesting that neither plane has a retractable gear. That tells me that a good, efficient design doesn't need RG, though that point has probably been clear for a long time.
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That's the one. One of the big items he that he states lets him run so lean is a modern, modified digital ignition system.
 
There is a guy at my airport that talks about running super LOP in his RV. I think he has one set of spark plugs set for normal operation and the other set to fire at something like 30* before TDC to ignite the lean mixture.

Those numbers may be off but that's what he does.
 
Sac Arrow said:
Obviously he is doing something right. I would think you would start losing volumetric efficiency if you get too lean of an A/F ratio, but maybe 300 LOP on his engine hasn't reached that point, I don't know. Certainly I like what he's doing.

(EDIT: Metering power by running extremely lean on a wide open throttle is far more efficient than throttling to control power at a richer setting, even if still lean of peak.)
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Post #1 is talking about the guy getting 55 MPG.

Post #2 is talking about another guy that is getting 300f LOP.


I think. :lol:
 
Geico266 said:
Post #1 is talking about the guy getting 55 MPG.

Post #2 is talking about another guy that is getting 300f LOP.


I think. :lol:
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Aaah the classic one guy got this and the other guy did that. Gets me every time!
 
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