UPDATE 1-Northrop beats estimates, raises profit forecast again

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July 26 (Reuters) - Northrop Grumman Corp reported a higher-than-expected rise in quarterly profit, helped by increased demand for its manned aircrafts, and the maker of Global Hawk surveillance planes raised its full-year profit forecast for the second time.

Sales rose at two of its three main businesses with revenue in the aerospace unit, which makes manned aircraft, drones and space craft, up 14 percent at $2.97 billion.

The company is expected to benefit from increased demand for F-35 fighter jets. Northrop supplies the center fuselage for F-35 jets, which forms a significant portion of the aircraft's internal weapons bay and fuel capacity.

The F-35 is the Pentagon's costliest arms program.

Larger rival Lockheed Martin Corp, the prime contractor for the F-35 program, last week posted a higher-than-expected quarterly profit on strong demand for F-35 jets.

For 2017, the company now expects earnings per share of $12.10 to $12.40, from an earlier forecast of $11.80 to $12.10.

Net earnings rose to $552 million, or $3.15 per share, in the second quarter ended June 30, from $517 million, or $2.85 per share, a year earlier.

Analysts expected earnings of $2.87 per share, according to Thomson Reuters I/B/E/S.

Total sales rose 6.3 percent to $6.38 billion, while analysts on average expected revenue of $6.21 billion. (Reporting by Sweta Singh in Bengaluru; Editing by Martina D'Couto)