Dual engine failure caused a plane to crash in the Nigeria city of Lagos last month, killing more than 150 people, investigators have said.
The crew of the Dana Air flight first experienced problems with their throttles, Nigeria's Accident Investigation Board report said.
Speculation that contaminated fuel had affected the engines was unfounded, though more tests are to be done.
The report also revealed that one of the aircraft's black boxes melted.
The commercial aircraft was flying from the Nigerian capital, Abuja, to Lagos when it crashed into a printing works and residential buildings in Iju, a busy suburb north of the airport, and burst into flames.
All 153 people on board and 10 on the ground died, AIB's preliminary report into the accident said.
The aeroplane's cockpit voice recorder captured 31 minutes of conversation between the pilots, the report said.
About half an hour before the crash at 15:15 GMT, the crew discussed a problem with the engine indicator light and the engine throttle setting, it said.
As the plane was preparing to land and the landing gear and flaps were extending, the engines failed.
"We just lost everything. We lost an engine. I lost both engines," the report quotes the captain as saying at 15:43.
The flight data recorder was found by investigators but the digital tape in its memory "succumbed to the post crash fire and melted, consequently no data could be recovered", the report said.
Although Nigeria's air safety record has improved in recent years, the country has a history of major passenger plane crashes - this is the fourth crash in the last decade in which more than 100 people were killed.
Lagos airport is a major hub for West Africa and saw 2.3 million passengers pass through it in 2009, according to the most recent statistics provided by the Federal Airports Authority of Nigeria.