(Reuters) - General Electric Co (>> General Electric Company) cut the profit growth estimate for its core industrial businesses on Friday, citing weakness in Europe and sliding wind turbine sales, unnerving Wall Street and pushing its stock down in morning trading.

The world's biggest maker of jet engines and electric turbines now expects industrial profit to rise by high single digits to double digits this year. Previously it had forecast double-digit growth.

Chief Executive Jeff Immelt blamed slumping sales of wind turbines and gas turbines for the outlook cut, as well as the weakening European economy. But he said he still expects overall earnings, which include GE Capital, to improve this year.

Wall Street analysts, which earlier in the day hailed GE's better-than-expected first-quarter revenue, grew unnerved as the new outlook was disclosed in a conference call. Shares of GE dropped 4 percent to $21.76 in morning trading.

"The level of uncertainty in terms of their ability to meet their goals has risen a little bit," said Perry Adams, portfolio manager at Northwestern Bank, which holds GE shares.

GE sold 584 wind turbines in the first quarter, down 15 percent from a year earlier, due in part to a delay in the renewal of a federal tax credit for buyers in renewable energy. Profit in the power & water unit - which sells wind turbines - fell 39 percent, and results aren't expected to improve.

"We believe it's going to be hard for our power and water business in 2013 to meet 2012" results, Immelt said on the conference call.

Europe also remains a weak spot for the company - Immelt said sales there were "weaker than expected" - and could drag on 2013 profit, GE said.

REVENUE BEATS

Strong sales of jet engines and home appliances helped GE's first-quarter revenue beat expectations, assuaging fears of a miss after a lukewarm report on March U.S. factory activity.

GE said revenue rose slightly to $35 billion, surpassing the $34.51 billion analysts had expected, according to Thomson Reuters I/B/E/S.

"That is a beat on revenue, and that's important because the Street has been very worried about revenue numbers at industrial firms because the quarter appears to have tailed off in March," said Jack DeGan, chief investment officer at Harbor Advisory Corp in Portsmouth, New Hampshire, which owns GE shares.

The Institute for Supply Management said earlier this month that U.S. factory activity grew at the slowest rate in three months in March, suggesting the economy lost some momentum at the end of the first quarter.

GE shipped 596 commercial jet engines during the quarter, boosting profit at the aviation unit by 9 percent. The company also touted a recent contract with Boeing Co (>> The Boeing Company) to supply engines for the 777 aircraft.

Despite price increases, consumers gobbled up GE's refrigerators, stoves and microwaves, boosting profit in the home and business solutions unit by 39 percent.

The company's order backlog - a closely watched indicator of future sales - rose to $216 billion from $210 billion in the fourth quarter of 2012. Backlog can be a positive sign that customers are willing to wait in line for a company's products, or a sign that a company is having a hard time meeting demand. GE's backlog has grown consistently in recent quarters.

"To me, when you see a trend, year over year, repeating itself, there's a business management issue. Eventually, that's got to change," said Oliver Pursche, president of Gary Goldberg Financial Services, which owns GE shares.

GE said it will slash costs by $1 billion this year, part of an effort to offset weak sales.

Fairfield, Connecticut-based GE said it earned $3.53 billion, or 34 cents per share, in the first quarter, compared with $3.03 billion, or 29 cents per share, a year earlier.

Excluding one-time items, profit was 35 cents per share, matching analysts' average forecast, according to Thomson Reuters I/B/E/S.

DIVIDEND

GE sold its remaining 49 percent stake in NBC Universal in February and then announced it would use cash from the sale to fund $18 billion in buybacks and dividend payouts this year.

The $18 billion figure includes $10 billion of shares the company plans to buy back and GE's dividend, which the company hiked in December by 12 percent to 19 cents per share quarterly.

The NBC sale helped GE's cash balance jump to $138.1 billion from $125.9 billion in the fourth quarter of 2012. The rise has led some investors to hope for yet another dividend hike.

"I expect it (dividend increase) to go from 19 cents to 21 cents ... but I don't expect it this quarter. Maybe next quarter," DeGan said.

On the conference call, Immelt said he remains committed to the plan to remunerate shareholders this year with $18 billion in buybacks and dividends. The company's annual meeting with shareholders is scheduled for New Orleans next week, and some investors said they expect a dividend announcement then.

Prior to selling NBC, GE had focused much of its efforts in recent years on scaling back its financial arm, making it less dependent on short-term funding and focusing more closely on a handful of operations, such as financing the sale of industrial equipment and lending money to mid-sized businesses.

GE has said it wants to grow its manufacturing and industrial units, a return to its roots. Earlier this month it bought oilfield pump maker Lufkin Industries Inc (>> Lufkin Industries, Inc.) for $2.98 billion, boosting its presence in the fast-growing market to extract oil and natural gas from shale rock.

(Reporting By Ernest Scheyder; Additional reporting by Ryan Vlastelica, Patricia Kranz and Chuck Mikolajczak; Editing by Lisa Von Ahn and John Wallace)

By Ernest Scheyder