Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Airline stocks are falling fast today, as the rising price of oil has investors fleeing the industry. United Continental (NYSE: UAL), Delta Air Lines (NYSE: DAL), and JetBlue Airways (Nasdaq: JBLU) have fallen 10%, while US Airways (NYSE: LCC) is down 12%.

So what: Oil is up 3.5% today to a high of $106.48, the highest price we've seen since May 2011. Since oil directly impacts jet fuel prices and therefore variable operating costs, the theory is that earnings will be dinged as a result.

Beyond just impacting costs, there is also concern that high energy prices could put a damper on our economic recovery just as it's getting rolling. If that happens, travel will head down again, hurting the revenue side of the business.

Now what: This is why owning airline stocks is a risky business. There are so many things out of your control, like the price of oil and the macroeconomy, which is a major contributing factor to very volatile earnings.

Buying or selling at this point is really a bet on oil prices, and in turn a bet on how Iran, Syria, and other countries in the Middle East will impact the global flow of oil. Right now there isn't any short-term danger that supply will be disrupted, but if Iran tries to close the Strait of Hormuz or Syria's chaos spreads, all bets are off. This just isn't the time this Fool would attempt to get into airline stocks.

Interested in more info on airline stocks? Add them to your watchlist below.