The results of tests on some of the 121 people killed in Sunday’s air crash north of Athens indicated yesterday that the victims had not inhaled any carbon monoxide, thereby quashing one of the theories about the cause of the accident, although investigators were boosted by the discovery of the second black box recorder. The coroner heading the tests on the bodies recovered from the scene, Phillipos Koutsaftis, said that toxicological tests on six of those on board, including the co-pilot, had shown no traces of carbon monoxide. He said one stewardess had a level of 7 percent, but that this was negligible since it was the equivalent to smoking a couple of cigarettes. «We are still doing tests for other gases, poisons, drugs and alcohol,» Koutsaftis said. The lack of carbon monoxide seems to rule out the idea held by some experts, that a problem with the air-conditioning system or some kind of electrical fire had led to the release of poisonous gas into the cabin, which knocked out passengers and crew. The pilots of the two F-16 Greek air force jets that shadowed the aircraft before it crashed into a mountainside in Grammatiko, say they saw the oxygen masks on the plane had been activated and that the co-pilot was slumped over the controls. The pilot was missing from his seat. His body is one of three yet to be recovered. Investigators are hoping that some clues about what happened in the cockpit might be provided by the black box voice recorder, which was recovered at the crash site. It had been feared that the recorder had been destroyed in the crash, for only its casing had been found until yesterday. The recorder was found in a ravine near the tail wing of the plane, which was the only part of the aircraft to remain virtually intact. The voice recorder will be sent to experts in Paris for analysis. They have already been sent the data recorder, which keeps the plane’s technical information. Records from the Defense Ministry and NATO, obtained by Kathimerini, show that the plane entered Greek air space at 34,000 feet and, apparently on automatic pilot, maneuvered above Attica before maintaining a holding position above the nearby island of Kea. The plane circled the island at least nine times before the automatic pilot seems to have been disengaged; it then headed back to Attica, where it finally crashed. Questions are being asked about the role of the Civil Aviation Authority, as the records indicate that no attempt to contact the plane was made, as is customary, when it entered Greek air space. Controllers only tried to contact the plane when it failed to descend for its approach to land at Athens International Airport. The air force was first informed of a problem at 10.24 a.m., but 23 minutes later was told that the plane had a technical problem which it seemed to have solved. The air force decided to scramble the two F-16s anyway, whose pilots first made eye contact with the plane at 11.20 a.m. – over two hours after it took off from Larnaca and the captain had reported a problem with the equipment cooling system before losing radio contact.