Hi fmw thanks for the answers, but somethings are still not completely clear to me.
You can use the current draw figure from your motor/prop combination to calculate the amount of time you can fly.
How can I do this? I know the manufactures of the motors put some figures in their websites like the maxcontinuouscurrent or max surge current, but which one should I use? What is the difference between those two numbers? And how do I insert the prop in the calculation? I know that this figure is difficult but all I want to know is basically how long can I fly If the engine is working at 100% and the batteries are fully charged. From there I can find a more realistic figure while flying and trial-and-error.
Right now I want to understand the basic behind the manufacturer selections of motor, esp and batteries so from there I can make my own selections in the future.
I<span class="Apple-style-span" style="font-family: Verdana, Arial; font-size: 13px; -webkit-border-horizontal-spacing: 1px; -webkit-border-vertical-spacing: 1px; ">take lots of batteries to the field personally.I never take a charger.</span>
How big of a number are we talking here? How much flight time in average do you get from your models?
Thanks again.<br type="_moz" />