(Reuters) - Boeing Co (BA.N) reported a 23 percent increase in core fourth-quarter profit on Wednesday, topping analysts' estimates and sending its shares up 4.3 percent.
Boeing forecast a rise in cash flow to $6.2 billion in 2015, at the top end of expectations, from $4.3 billion at the end of the year.
Boeing's results showed strong year-end performances across its businesses. But analysts saw more strength in defense, where profit margins widened. In contrast, commercial airplane margins narrowed as Boeing delivered more 787 Dreamliners, which remain costly to produce.
Despite the concerns, Boeing's "solid 2015 cash flow guidance suggests confidence on lower 787 unit costs," JPMorgan analyst Joseph Nadol said in a note to clients.
The cash forecast for 2015 was "a very robust number," and gives Boeing flexibility to return money to shareholders, said Peter Arment, an analyst at Sterne Agee.
For 2015, the world's biggest plane maker forecast core earnings, excluding pension and other costs, of between $8.20 and $8.40 a share, below the average analyst estimate of $8.64. Analysts expected a weaker profit outlook because of tax items that boosted 2014 results.
Net profit rose to $1.47 billion, or $2.02 per share, in the quarter from $1.23 billion, or $1.61 per share, a year earlier.
Core earnings increased to $2.31 per share from $1.88. The latest result beat the $2.11 average that analysts expected, according to Thomson Reuters I/B/E/S.
Boeing's deferred production cost balance for the Dreamliner program rose to $26.1 billion at year end from $25.2 billion in the third quarter. The figure represents the costs of making 787s, averaged over the first 1,300 aircraft that are deferred from its income statement.
The rise was greater than some analysts expected, but in line with past increases. However, it suggested Boeing may struggle to cap the total balance at $27 billion as it had targeted, Nadol said.
The company added $12 billion worth of orders to its total production backlog in the quarter, pushing the backlog to $502 billion from $490 billion at the end of the third quarter.
As announced earlier, jetliner deliveries rose to 723 in 2014 from 648 in the previous year, topping those by rival Airbus Group (AIR.PA).
For 2015, Boeing said it will deliver 750 to 755 jetliners.
Boeing shares jumped $5.75 to $138.25.
Reporting by Sweta Singh in Bengaluru and Alwyn Scott in New York; Editing by Sriraj Kalluvila, Kirti Pandey and Jeffrey Benkoe