Washington, July 24 - Boeing Co. has reported better-than-expected second-quarter results but failed to answer when will its troubled 787 Dreamliner, 27 of which have been ordered by Air India, fly for the first time.

Boeing has determined how to fix a 787 wing-body problem, discovered in late May, but it still doesn't know how long the modifications will take, according to Chairman and Chief Executive Jim McNerney cited by the Wall Street Journal.

Problems on the Dreamliner, which was Boeing's hottest-selling commercial aircraft ever, already have pushed the first deliveries of the plane back nearly two years and cost the company millions of dollars in penalties and concessions to customers.

During its earnings conference call, analysts pressed McNerney and Chief Financial Officer James Bell for additional details on the programme's timetable and the cost impact on the programme and the company at large, the Journal reported.

'The delays are obviously putting pressure on the programme's profitability,' said Bell. So far, the company has indicated the programme has been profitable, though analysts are looking for signs that Boeing could take a charge in the coming quarters once it updates cost estimates, the leading US financial daily said.