Wednesday, Northrop (NOC), which has a roster of promising products and robust cash flow, lifted its quarterly common dividend 7.5%, to 43 cents a share from 40 cents, marking the sixth consecutive year of higher distributions. Dividends have more than doubled in that stretch, and have been paid without interruption since 1951. In March, defense-industry brethren General Dynamics (GD) and Raytheon (RTN) raised their quarterlies, too. Northrop's new dividend is payable June 13 to holders of record June 1, and the stock goes ex-dividend May 28. Los Angeles-based Northrop is the world's No. 2 military contractor (behind Lockheed Martin [LMT], with Boeing [BA] a close third) and the No. 1 builder of conventional warships and nuclear-powered aircraft carriers. Traded on the Big Board, the shares change hands just under 50 and, with the new payout, yield 3.57%. Their 52-week range is 76.32 to 33.81. The company bought back $1.6 billion of stock in 2008.

An $11 billion electricity and natural-gas company, Xcel Energy (XEL) modestly boosted its quarterly common dividend Wednesday, to 24.5 cents a share from 23.75 cents, for a 5.77% yield. Holders of record June 25 will receive the new payout July 20. The ex-date is June 23. The company said the increase "is consistent with our goal of growing the dividend 2%-4% annually." Xcel has been making payouts since 1910. The NYSE-listed shares recently traded around 17; their 52-week range is 22.39 to 15.32. Standard & Poor's rates the stock Buy, while Edward Jones & Co.'s opinion is Hold. Headquartered in Minneapolis, Xcel primarily serves eight Midwestern and Western states. Its first-quarter earnings rose 14% from the level a year earlier, to 38 cents a share, although operating revenue fell 11%. Xcel expects sales of both power and gas to slide 1% this year. It estimates full-year profit of $1.45 to $1.55 a share, against 2008's $1.46.

Aaon (AAON), a producer of air-conditioning and heating equipment, sweetened its semiannual common dividend Wednesday to 18 cents a share from 16 cents. The respective payment, record and ex- dates are July 2, June 11 and June 9. Dividends were initiated in 2006. In announcing the increase, the company cited record sales and earnings in 2008, plus strong free cash flow. Its shares (AAON) yield 1.74% and are trading near their 52-week high of 23 (the 12-month low is 12.79). AAON was named one of America's 200 Best Small Companies in 2008 and also in 2000-2002 by Forbes magazine.