stratobee
Cleared for Takeoff
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stratobee
I thought I'd start a new thread on this subject as it was getting off topic in the speed thread.
In theory all aircraft would show best fuel economy (endurance) at best glide (or Vy) speed. That's when the curves meet.
I came across this interesting paper. It talks about something called the Carson Speed, which is defined as "Least amount of fuel per knot of speed" or Fuel Flow/Knot. It's calculated as being roughly 1.3xVy (or best glide) but taking into the consideration the GS, which is very interesting. Example: My aircraft's Carson Speed would be 152kts. If you have a tailwind, you reduce the MP until your GS shows the Carson Speed and vice versa if you have a head wind.
I am unclear if this Carson method produces less total fuel consumption over a given distance compared to flying at best glide or Vy. I'm assuming it does, depending on winds, but I haven't started using my brain quite yet this morning (some would argue never).
http://pointsforpilots.blogspot.com/2013/07/flying-frugally.html
Also, again, here's a link to Klaus Savier's Vari-EZE getting 45mpg at 207mph. Which is kind of impressive.
http://www.wired.com/autopia/2009/11/45mpg-at-207mph/
For you that have fuel flow meters - have you ever reduced to Vy or best glide speed and seen what the fuel consumption is there? Be interesting to know for various types.
In theory all aircraft would show best fuel economy (endurance) at best glide (or Vy) speed. That's when the curves meet.
I came across this interesting paper. It talks about something called the Carson Speed, which is defined as "Least amount of fuel per knot of speed" or Fuel Flow/Knot. It's calculated as being roughly 1.3xVy (or best glide) but taking into the consideration the GS, which is very interesting. Example: My aircraft's Carson Speed would be 152kts. If you have a tailwind, you reduce the MP until your GS shows the Carson Speed and vice versa if you have a head wind.
I am unclear if this Carson method produces less total fuel consumption over a given distance compared to flying at best glide or Vy. I'm assuming it does, depending on winds, but I haven't started using my brain quite yet this morning (some would argue never).
http://pointsforpilots.blogspot.com/2013/07/flying-frugally.html
Also, again, here's a link to Klaus Savier's Vari-EZE getting 45mpg at 207mph. Which is kind of impressive.
http://www.wired.com/autopia/2009/11/45mpg-at-207mph/
For you that have fuel flow meters - have you ever reduced to Vy or best glide speed and seen what the fuel consumption is there? Be interesting to know for various types.
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