BANGKOK — br The Indonesian authorities were searching on Sunday afternoon for an AirAsia jet with 162 people on board that lost contact with air traffic controllers hours earlier, the airline and government officials said. br br The plane, Flight QZ8501, left the Indonesian city of Surabaya around 5:30 a.m. for the short hop to Singapore, a flight that usually takes about two hours, the airline said. Air traffic control lost contact with the Airbus A320-200 at 6:17 a.m., about 40 minutes later, Indonesian officials said. br br “At this time, search-and-rescue operations are in progress, and AirAsia is cooperating fully and assisting the rescue service,” the airline said in a statement on Facebook. br br Flightradar24, a website that uses a global system of beacons to monitor air traffic, said the aircraft had been over the Java Sea, which separates the islands of Borneo and Java, when the plane’s signal was lost.