Industrial conglomerate Textron (NYSE: TXT) has rocketed up more than 58% over a 52-week period, boosted by a great second-quarter earnings report that smashed EPS expectations. While shareholders have plenty of reason to smile about the stock's growth, the economy's volatility sparks fears about this company's sustained results. Is Textron headed for a slowdown -- and should you sell now to save your profits?

Concentration in diversification
Textron operates as a conglomerate, but it's nowhere near as diversified as some of the other big boys in this area. The company primarily produces aerospace products, components, and services, with a secondary financial unit and a general industrial products segment rounding out Textron's divisions.

Here's where things get tricky. While Textron's yearly revenues since the recession have yet to catch up to their pre-recession totals, the company's Bell helicopter division has never looked better. Bell's revenue for the most recent quarter totaled more than a third of all Textron's revenues, nearly a 25% jump year over year.

Meanwhile, no other segment for the company did particularly well. Its systems branch, which handles a number of diversified defense and aviation products and services, dipped slightly in year-over-year revenue, while its finance, Cessna aircraft, and industrial divisions all notched up small gains that were dwarfed by Bell's success. In pure profit terms, Bell comprised a full half of Textron's earnings.

Still too shaky
That sounds great if you're concerned with the here and now, but Bell derives more than a third of its revenue off solely the V-22 Osprey helicopter program for the U.S. military. While the program's grown Textron's bottom line, statements by the Marine Corps that future V-22 purchases could be cut won't help the company's future financials. The most recent quarter did see a welcome uptick in commercial helicopter sales, but Textron has to do a better job with its other segments to keep up its revenue diversity in the face of a volatile economic and federal budgetary climate.

Unfortunately for investors, Textron's numbers haven't matched up with the other conglomerate giants. While defense-oriented rivals like United Technologies (NYSE: UTX) and Honeywell (NYSE: HON) trade at similar valuations to Textron's 18.7 P/E, they both also sport net margins that dwarf Textron's measly 3.5% net margin. Textron also fails to come close to industry averages for return on investment with a 6.1% figure.

Although Wall Street growth estimates for Textron may fly high, this conglomerate has too many worrying signs to make it a good candidate for your portfolio. The company may be soaring now with the economy rebounding nicely, but one slip in global economic fortunes and Textron could see its recent gains erased. If you want a steady, secure conglomerate to add to your portfolio, avoid this stock's shaky future.

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