Q. I know that Tuesday nights are the best nights to look for airfare, but I need to know the real reason behind it. Is it true that the airlines recycle their airfares on that day and that's why?

A. Actually, Airfarewatchdog doesn’t believe that there’s just one single day to find a low airfare. Yes, it’s true that at least for now, Southwest and Airtran usually launch their sales on late Monday night/Tuesday morning, so by Tuesday other airlines have matched. Tuesday is definitely a good day to search for domestic airfares, at least on routes served by Southwest and Airtran. And on Tuesday or Wednesday, most airlines have also posted their last minute weekend deals. As the week progresses, seats at the lowest fare may be grabbed by other travelers. But recently we've also seen a lot of great sales pop up on a Friday. Sooo, we strongly urge readers not to only look for airfares on Tuesday. A huge price drop on a route you want to fly could happen at any second of the week. Not only do the airlines constantly adjust airfares themselves, but they tweak the number of seats offered at the lowest fare. Someone could be holding the last seat at the cheapest fare and decide to cancel. Voila, the fare is yours if you were persistent enough to look. We have seen amazing deals pop up on Fridays, Saturdays, or even Thursdays. The key to finding a low airfare is to sign up for free airfare alerts (do a web search for “airfare alerts” to see what’s available) and to do your own searches as well. Search several times a day every day of the week and you’ll be amazed at how often fares change on any given route. So if you only look for airfares on Tuesday you’ll miss out on some great deals!