In an interview with The Associated Press, Manuel Bautista said a failure of one of the Spanair MD-82's two engines by itself - if such a failure did in fact occur - should not normally be enough to bring down a modern aircraft because they are designed to fly on just one if necessary.
"A set of causes probably came together to cause the accident," Bautista said.
With an investigation under way with help from the United States and the airplane's manufacturer, he said it was too early to say if human error was involved.
Bautista said he has seen - but would not comment on - video footage from Madrid airport that shows the doomed airliner trying to take off. The newspapers El Pais and ABC said it shows no engine explosion, contrary to some witness accounts.
The plane abandoned one takeoff attempt because of a mechanical problem with what the airline called an air intake temperature gauge near the cockpit. The gauge was essentially turned off and the plane cleared for takeoff. It crashed on takeoff.
Aviation experts have said the gauge problem, usually a relatively minor glitch, was unlikely to have caused the crash, but Bautista would not rule out the possibility that it contributed to the accident.
"A problem with a temperature sensor may not matter at all or it can be very important, depending on what other circumstances accompany it," Bautista told the AP. "We will have to see what other issues were present."
On Thursday, a survivor told of the heaving,of the MD-82's flight, saying she feared she was going to die.
"The plane was rocking back and forth, until I suspected it was going to fall," Ligia Palomino, a 41-year-old emergency rescue worker who happened to be on board, told Spain's Cadena Ser radio station. "I saw people, smoke, explosions. I think that is what woke me up because I had lost consciousness."
"I thought that if help did not arrive soon I would die," said Palomino, who suffered leg injuries and a broken rib.
The government released a list of the nationalities of 19 foreigners from at least 11 countries who were on the plane. Of the 19, only one survived, a Swedish citizen.
The other 10 countries are: Germany with five citizens among the dead, France with two, and one each from Mauritania, Turkey, Brazil, Indonesia, Bulgaria, Italy, Colombia and Gambia. The nationalities of three other foreign victims had yet to be determined. The list did not name the foreigners.
As the shock of the tragedy began to sink in, Spain began three days of mourning Thursday. Flags in Madrid flew at half-staff and silent vigils were held at noon around the country. The king and queen visited the morgue, consoling relatives of those who died.