Boeing Co posted a larger quarterly profit on Wednesday that topped analyst forecasts on strong operating margins and the company upped its profit forecast for 2011.

Shares of the company rose 3.6 percent to $66 in premarket trading.

The world's largest aerospace and defense company, which competes with EADS unit Airbus, said third-quarter profit rose to $1.1 billion, or $1.46 per share, from $837 million or $1.12 per share a year before.

The results topped a Wall Street average forecast for $1.10 per share, according to Thomson Reuters I/B/E/S.

Today the shares are going to trade on EPS numbers, but long-term I think it's order books, said Neal Dihora, equity analyst at Morningstar.

If we're entering into a slow economic period, we're not going to get as many orders, Dihora said.

Boeing's earnings per share guidance increased to $4.30 to $4.40, reflecting strong core performance from its previous forecast for $3.90 to $4.10. The company, however, narrowed its 2011 revenue forecast to between $68 billion and $70 billion from $68 billion to $71 billion.

Boeing, which splits its business between defense and commercial airplanes, said quarterly revenue increased 4 percent to $17.7 billion, while its order backlog grew to $332 billion, from $323 billion at the beginning of the quarter.

Revenue for Boeing's commercial airplanes division increased by 9 percent to $9.5 billion on increased deliveries of its airplanes.

Earlier this month, Boeing said it delivered 127 commercial airplanes in the third quarter including 100 of its best-selling 737 narrowbodies and 21 widebody 777s. The number of deliveries was up slightly from the 124 reported for the year-ago quarter.

Boeing gets paid for its airplanes at delivery. Boeing's commercial airplane delivery guidance for 2011 is now about 480, down from the previous guidance of between 485 and 495.

Revenue for Boeing's defense, space and security business was $8.2 billion, steady from a year ago.

The financial results were reported on the day of the first commercial flight for Boeing's long-delayed and hotly anticipated 787 Dreamliner, a light-weight, carbon composite wide-body.

The first 787 was delivered to All Nippon Airways last month, capping three years of delays for the development program. The first paying customers rode ANA's Dreamliner to Hong Kong from Tokyo.

Now analysts want to know whether Boeing can ramp up its production rate for the plane to 10 per month by the end of 2013 as promised and when the program will be profitable. Boeing has taken more than 800 orders for the plane.

Boeing said on Wednesday that consistent with accounting practices applied on other new airplane programs, the 787 initial accounting quantity was set at 1,100, on which it will calculate its probability going forward.

Boeing Chief Executive Jim McNerney has previously said he expects the 787 program to be profitable from day one based on the company's accounting practices.

(Reporting by Kyle Peterson, editing by Gerald E. McCormick and Matthew Lewis)