Warning systems on both planes also failed to alert pilots to the impending crash, Col. Rufino Antonio da Silva Ferreira said at a news conference.
He said the executive jet, a Brazilian-made Legacy owned by ExcelAire Service Inc. of Ronkonkoma, N.Y., "remained at 37,000 feet until the moment of collision," while Ferreira said it should have been flying at 36,000 feet.
He said neither crew saw the other plane coming.
"No one saw anyone," he said. "No one tried evasive action."
In the Sept. 29 crash, the Gol Airlines Boeing 737-800 plunged into Brazil's dense jungle, killing all 154 people aboard. The Legacy landed safely at an air force base with all seven people aboard unharmed.
Authorities have seized the passports of the American pilots of the Legacy so they can't leave the country.
Prosecutors have said that Joseph Lepore, 42, of Bay Shore, N.Y., and Jan Paladino, 34, of Westhampton Beach, N.Y., could be charged with involuntary manslaughter if they are found responsible for the crash. The pilots have denied wrongdoing.
ExcelAire has denied its pilots violated instructions. Lawyer Robert Torricella said the Legacy was cleared to fly at 37,000 feet all the way to the northwestern city of Manaus in the Amazon jungle
even though odd-numbered altitudes are reserved internationally for southbound flights.
"The flight plan was cleared by air traffic control for the Legacy to fly at 37,000 feet to Manaus," Torricella said by telephone. "The (pilots) never received a contrary order."
The Legacy flew past Brasilia at 37,000 feet and "there is no record of a request ... to the control tower to change altitude," said the report released by Ferreira.
The planes collided over the Amazon jungle state of Mato Grosso, and the Boeing went into a nosedive and crashed in the jungle.
"The crash was violent. It disintegrated," Ferreira said.
Ferreira said he had not interviewed air traffic controllers and was waiting for a technical report on the condition of the transponders, devices that signal a plane's presence and altitude.
The two American pilots were interviewed and were "cooperative," Ferreira said.
ExcelAire said in a statement that the U.S. pilots union and their international umbrella federation were calling for the release of the two.
"Thus far, only contradictory facts, rumor and unsupported allegations have been forthcoming from Brazilian government officials," the International Federation of Air Line Pilots' Associations, which represents more than 100,000 airline pilots in more than 95 countries, said in a statement.
The federation "calls on the Brazilian authorities to expedite the conclusion of an independent technical investigation into (the crash) ... and that these pilots be allowed to return to their homes forthwith."