"Milage" versus speed

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I've heard numbers around 45 km/h for best "milage" and used that for my litchi missions but then I thought that it would be nice to see if the theoretical values match with the real values....
In the litchi log you have current draw and battery voltage which gives you the power consumption in watts.
You also have speed and time and that gives you the distance.
By dividing the power consumption with the distance covered over one second you get watt*seconds/meter.

I did a mission in litchi with speeds from 10,15,20,25,30,40 km/h (no wind at all) and also used sport mode to get higher speed. I opened the litchi log in excel and calculated the numbers and it actually matched up really nice!

The best milage seems to be around 40-50 km/h so for long flights use sport mode.

But what happens when you add wind to the equation?
My gut feeling is that you should use sport mode and full speed against the wind and also fly low (just like the birds handle head winds).

Y-axis is (Watt x Second) / meter, X-axis is speed in km/h
milage.jpg

/hakan
 
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I've heard numbers around 45 km/h for best "milage" and used that for my litchi missions but then I thought that it would be nice to see if the theoretical values match with the real values....
In the litchi log you have current draw and battery voltage which gives you the power consumption in watts.
You also have speed and time and that gives you the distance.
By dividing the power consumption with the distance covered over one second you get watt*seconds/meter.

I did a mission in litchi with speeds from 10,15,20,25,30,40 km/h (no wind at all) and also used sport mode to get higher speed. I opened the litchi log in excel and calculated the numbers and it actually matched up really nice!

The best milage seems to be around 40-50 km/h so for long flights use sport mode.

But what happens when you add wind to the equation?
My gut feeling is that you should use sport mode and full speed against the wind and also fly low (just like the birds handle head winds).

Y-axis is (Watt x Second) / meter, X-axis is speed in km/h
View attachment 64049
/hakan
Good work! your data matches what many long rangers report, from 28mph to 32mph is what I have noticed. When I fly against the wind I stay low and come back at higher elevation for the extra push, I noticed a considerable gain in speed when I do this. BTW G35 metric is easier to calculate then imperial when you learn to use it, USA is one of the 3 countries on earth still using imperial. Liberia and Burma are the others.
 
Thanks for the picture, that gave me a good laugh :)
I used the metric system since I've grovn up with it and it makes all the formulas simple without any constants. I should have written speed in miles to make it easier for other readers also...but I was lazy...but I called the topic milage ;)
We still use horse power for petrol and diesel engines in Sweden even though they try to change to kw, changing units is tough!

Cheers
Hakan
 
I ask for this info a month or so back. Thanks that is great to know.
 
I just wish DJI would put kph instead of meters per second. I use mph in my bird because mps just does not do it for me. Next time you get pulled over by a police officer and he askes you ```Do you how fast you were going`` you can tell him I was only going 36 meters per second sir. (80mph)
 

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