Air Berlin, Germany\'s number two airline, said on Thursday it narrowed its losses in the second quarter, thanks to increased capacity utilisation on a reduced number of routes on offer. Air Berlin said in a statement that its net loss amounted to 38 million euros ($50.5 million) in the period from April to June, compared with a loss of 99.8 million euros in the same period last year. On an underlying basis, too, the carrier was able to narrow its operating loss to 8.1 million euros from a year-earlier loss of 29.4 million euros. Revenues were stable at 1.11 billion euros in the April-June period compared with 1.13 billion in the second quarter of 2012. \"In the second quarter, Air Berlin further increased its capacity utilisation, revenue per available seat kilometre (RASK) and revenue per passenger,\" the company said. The number of routes flown in the second quarter decreased from 520 in 2012 to 440 in the current year and capacity utilisation increased by four percentage points, to 83.7 percent. \"Our key numbers are moving in the right direction,\" said chief executive Wolfgang Prock-Schauer. Nevertheless, he cautioned that \"as a result of the generally muted economic conditions and the market environment, the ability to reach our targets is becoming increasingly challenging.\" But Prock-Schauer insisted that Air Berlin\'s efficiency-boosting programme would \"bear fruit later in the year.\" Separately, Air Berlin announced that it has agreed to sell up to 11 aircraft to a subsidiary of China\'s Minsheng Financial Leasing to reduce debt. The transaction includes five used Airbus A320 family aircraft owned by the airline, as well as two new aircraft that will be delivered next year, one from Airbus\' A320 family and a Boeing 737-800. In addition, Minsheng Commercial Aviation will have an option to buy four Boeing 737 and place them into the Chinese market. Financial details were not disclosed, but a spokesman said the transaction would generate a \"substantial three-digit million euro amount\" for Air Berlin.