This may very well be the case, for now. Flight time from a given battery pack hinges on a lot of variables, outside temperature, total battery usage time, percentage of full charge, amount and type of servos, and flying style just to mention a few. If you are just flying in circles for the most part and the Rx pack is fairly new and in optimum condition you might get 80 minutes from that pack, but as you start to gain confidence and begin doing a lot of loops, rolls, and inverted flight, it will cut down the actual flight time of the battery due to the higher current drain. It's best to use a good quality Expanded Scale Voltmeter (puts a load on the pack to simulate actual flying conditions) after every flight to be sure if it's safe to fly again before a recharge. If you are using a 4.8 volt pack you should recharge when it tests below 5 volts. Some will disagree with this and say it's OK to fly it right down to 4.8 volts. Personally, I don't feel it worth pushing them that far, but that's just my opinion.