ORIGINAL: CGRetired
You can also charge the battery after 3 or 4 or 5 flights (depending on your courage) and keep things safe.
Pushing things to the point of exhaustion is not necessarily in the best interest of neither the hobby nor the the owner of the plane, not to mention the potential victim that could be hurt by something falling out of the sky that weighs about 8 pounds traveling at about 50 miles per hour.
Why push it? What's the point? It can't be just to get another flight because with today's fast chargers, we can be back in the air in less than an hour. So, bring two planes and charge one while flying the other, or sit down with your buds and have a conversation about RC flying... or whatever tickles your fancy.
The point is to keep things safe. We say this over and over again. A Sanyo 4 cell 700 ma pack costs a whopping $11.99 -
http://www3.towerhobbies.com/cgi-bin...&I=LXFD90&P=ML as an example.
So, buy two. Check the voltage (personally, I use a voltwatch2) before and after each flight. If it's questionable, charge the battery... fly a different plane or pull the battery pack out and replace it with a fully charged pack and charge the one that you pulled out.
CGr.
Constantly recharging batteries before they get down to a cut off voltage is not good for them either. The best way to know the condition of your batteries is to use a loaded volt meter of a least a 250 mAH load for sport planes and 500 mAH load for giant scale or 3-d planes. Also you need to load test your batteries periodically on a charger to know what they are capable of. As a general rule once they deliver less than 70% of their rated capacity they get replaced. Again the best battery FAQ out there:
http://hangtimes.com/rcbattery_faq.html