A system malfunction forced the pilots of an AirAsia X flight from Kuala Lumpur to Jeddah to abort the flight and return to Malaysia on Sunday, the AirAsia Group's CEO said. The incident sparked fresh questions on social media about the Malaysian airline group's safety record as it struggles with the aftermath of the loss of Flight QZ8501 in late December with 162 people on board. "One auto-thrust not functioning properly. Actually okay to fly but we just returning it to base," Tony Fernandes said in a text message, calling it a "minor issue". Auto-thrusters are systems that ensure a plane continues to travel at a steady speed. Fernandes confirmed the Airbus A330 - operated by the long-haul arm of the AirAsia Group of carriers, AirAsia X - landed safely at Kuala Lumpur's international airport. Flight-tracking websites indicated AirAsia X Flight D7172 flew several wide circles over the Strait of Malacca to burn off fuel. Fernandes called the manoeuvre a "routine" precaution as the plane was heavily laden with fuel that normally would have been used up during the several-hour flight to the Saudi Arabian city. "Just burning off fuel as has lots of fuel as was going to Jeddah," he said. AirAsia said the passengers were later put on another plane. "As a safety precaution, and in full compliance with all international security and safety standards, the aircraft made a turn back," it said. Although QZ8501 was the AirAsia group's first deadly accident, it followed two deadly Malaysia Airlines incidents last year that killed more than 500 people and raised concerns among many travellers about the safety of the country's carriers. "What is happening with Malaysia and airplanes? This is really, really scary," posted one Twitter user.