By Chris Mayer
The economic center of gravity will not always reside in the United States. In fact, it's already in the process of shifting from the US to Asia and the Middle East. Forward-looking investors cannot afford to ignore this trend.One of my favorite ways to invest in the rapidly growing emerging markets is through the back door, so to speak. Invest in companies, wherever they are, that have what these economies need or want, but don't have. Airliner production is a classic example.I bet most Americans would be surprised to learn, for example, that the Middle East is a very important market for new jets. The Gulf's leading airlines – Emirates (out of Dubai), Etihad (out of Abu Dhabi) and Qatar Airways have become big reasons why Boeing and Airbus make any money. "The Middle East is still the hub of aviation growth," says Airbus CEO, Tom Enders.According to informed guesses, the Middle East will buy 1,400-1,700 planes over the next twenty years, at a cost of $240-300 billion. These planes will support passenger growth of nearly 5% annually over that timeframe. Many other developing nations around the globe are also becoming active buyers of passenger jets. Airbus just signed a $1.8 billion deal with Vietnam Airlines for four A380 super-jumbos and two A350s. Ethiopian Airlines recently put in an order for 12 A350s, at a cost of $3 billion. These are just two examples.The Asia-Pacific region, despite the impressive growth out of the Middle East, is still the largest buyer of aircraft. Over the next 20 years, for instance, the Asia-Pacific region will require close to 9,000 planes, at a cost of over $1 trillion.I've focused mostly on civil aviation. But there is also defense spending. In the Middle East, defense spending will probably rise to more than $100 billion by 2014, from only $36 billion now, according to a new study by consultancy Frost & Sullivan. That's why Lockheed Martin recently announced it would double its capacity to produce the C-130 Super Hercules – because of increased demand from the Middle East.Also, I can't end without saying a word about the world's urge to lower carbon emissions. The industry has pledged to cut its carbon emissions in half by 2050 – an effort that will require new planes with lighter material, different design and innovative engines.Despite all the good news on the aviation front, there is a fly in the soup that Boeing and Airbus will have to fish out before long: They are having a hard time making the planes on time. This is a rather fascinating subject on its own, given the history of aviation. In 1944, for example, Boeing used to crank out 16 B-17 bombers every 24 hours. Today, it's having a hard time producing one of its ballyhooed Dreamliners after more than two years of trying. Airbus has had its share of delays as well.Eventually, they'll sort it out. Eventually, they will build the new planes. There are lots of ways to play on these ideas as an investor, as these new planes ripple through the supply chain.My favorites are the titanium producers. Titanium is a lightweight metal. In fact, it has the highest strength-to-weight ratio of any metal, making it ideal for aircraft. The newer planes are titanium intensive, more so than in the past.Our play here is Titanium Metals (NYSE:TIE), the second-largest producer of titanium in the world. It has a solid financial position with lots of cash and no debt. It's stayed profitable, even through the slump. And Wall Street doesn't expect much from it, as analysts rate the stock as a poor performer. The potential upside when it comes makes it worth hanging onto. In TIE's heyday back in 2006, it was a $40 stock. Today, it's about $13. All cycles turn, remember. And this one will, too. The company only recently signed a new agreement with Boeing that will keep it as a key supplier through 2015.Titanium Metals has the potential to be a big winner once the aviation cycle gets in full swing again.