(New throughout with detail from conference call, analysts)
April 23 (Reuters) - Rising jet production helped Boeing Co generate substantial cash in the latest quarter, and the company said on Wednesday that it lavished the rewards on shareholders, sending its stock higher.
The unexpectedly strong cash flow soothed fears that plane production snags could hamper the outlook for buy-backs and dividends at the world's biggest plane maker, and suggested instead that there is scope for those rewards to rise.
Boeing's report "gives much more confidence about the ability to return cash," said Ken Herbert, an analyst at Canaccord Genuity Inc.
Boeing spent nearly $3 billion in the first quarter to buy back some 19 million shares and pay dividends, most of the expected amount for the year, according to analysts.
And yet the company sees scope for more this year, Chief Financial Officer Greg Smith suggested in a conference call. The company has allocated $8.3 billion to return over the next two or three years and has flexibility on the timing.
"We're committed to deploying our cash efficiently," Smith said.
Investors had been worried that Boeing's cash might be reduced because of a build-up of inventory of 787 planes, following production snags at its South Carolina assembly plant.
Boeing reported $615 million in free cash flow for the quarter, above the $545 million forecast by RBC Capital Markets. Free cash flow is the amount of money left from operations after paying tax and maintenance on plant and equipment.
"We think investors will be breathing a sigh of relief," on free cash flow, said Rob Stallard, analyst at RBC Capital Markets, in a note. "The actual result has turned out far better than some feared."
Boeing also said growth in the deferred cost of producing the 787 had slowed slightly in the quarter.
That suggested the company was on track to make its newest plane a cash spinner by the time the company steps up production to 12 a month in 2016. On a cash basis, the plane currently costs more to produce than it earns in revenue.
Boeing shares were up 2.1 percent to $130.24 in afternoon trading.
Investors also saw strength in widening operating profit margins to 11.8 percent in Boeing's commercial aircraft business, even though the backlog of orders slipped from the beginning of the year.
Though Boeing's order backlog of commercial and defense orders decreased slightly in the quarter, Chief Executive Jim McNerney said that Boeing expects to keep selling more planes than it makes for the foreseeable future.
In the longer term, however, Boeing faces a continued threat by rival Airbus for market share. Airbus is winning key orders from airlines, including a wide-body order by Brazil's third-biggest airline, Azul Linhas Aereas, announced on Wednesday. Boeing's 787 was a contender in that contest.
"It's a concern for Boeing if the sales split is 60-40 or 55-45 (favoring Airbus) because eventually that gets reflected in deliveries," Herbert said.
Boeing in recent months said it plans to move thousands of engineering jobs to regional centers, stirring great concern among political leaders, Boeing workers and the public in Washington state, where its main jetliner factories are located, though investors have not reacted with concern.
McNerney said there is always a tension between locating engineering work at the factories and putting it near the best talent for the job. But the company's aim is to strike the right balance.
"In the minds of most of us, these moves strengthen our company, strengthen our engineering capability," McNerney said.
Boeing's core earnings, which exclude some pension and other costs, rose to $1.76 per share from $1.73 a year ago. That easily topped the $1.56 mean estimate of analysts surveyed by Thomson Reuters I/B/E/S.
On a non-adjusted basis, however, Boeing's profit slid 13 percent to $965 million, or $1.28 per share, down from $1.11 billion, or $1.44 per share, a year earlier.
For 2014, the company lifted its core earnings forecast to between $7.15 per share and $7.35 per share, up from the prior forecast of between $7.00 and $7.20. The increase reflects a tax settlement gain to be taken in the second quarter, and Boeing left 2014 forecasts for revenue, operating cash flow and deliveries unchanged.
Revenue rose 8 percent to $20.47 billion in the quarter ended March 31 from $18.89 billion a year earlier.
Boeing's adjusted earnings included a $334 million charge from retirement plan changes in the first quarter for moving non-union employees to defined contribution plan savings plan from a defined benefit plan. The move takes place in 2016.
(Reporting by Alwyn Scott; editing by Andrew Hay)