(AP)
Updated: 2007-09-05 02:32

BUELACH, Switzerland - Four employees of a Swiss air traffic control company on Tuesday were convicted of negligent homicide in a midair plane collision that killed 71 people.

Investigators stand in front of the remains of a crashed Tupolev passenger plane near the village of Brachenreute, near the southern German town of Ueberlingen at Lake Constance in this July 3, 2002 file photo. [Reuters]

A district court in Buelach, near Zurich, sentenced three midlevel managers to one-year suspended prison terms, while the other employee - a project manager - was ordered to pay a fine of 13,500 Swiss francs (US$11,200; euro8,250).

The four employees of Skyguide were found responsible in the July 1, 2002, collision of a Bashkirian Airlines plane and a DHL cargo jet near the south German town of Ueberlingen. The two cargo pilots and everyone on the passenger plane were killed.

Four other officials of Skyguide were acquitted of wrongdoing in the accident, which killed dozens of Russian schoolchildren and their families on a holiday trip to Spain. Although they were over Germany, the planes were in airspace controlled by Skyguide.

The only air traffic controller on duty at the time of the accident, Danish-born Peter Nielsen, was stabbed to death in 2004 by a Russian man whose wife and children died in the crash.

Vitaly Kaloyev is currently serving a prison sentence of five-and-a-quarter years for killing Nielsen.

Some of the defendants, who have not been identified because of Swiss privacy laws, blamed Nielsen for not following proper procedures.

But prosecutors in the trial said a culture of negligence and lack of risk awareness at the company contributed to the accident, and that it was not solely Nielsen's fault.

Francis Schubert, Skyguide's interim CEO, said the company has "learned the lessons from this tragic event and has done everything to ensure that an accident of this kind cannot happen again."

He said the tragedy was the result of a number of factors including people, technology and procedures.

"The legal proceedings and now the court's judgments have been a very difficult and emotional time for everyone concerned," Schubert said.

Presiding Judge Rainer Hohler said the three sentenced to suspended prison terms were responsible for ensuring that at least two air traffic controllers were on duty. They also should have informed the neighboring control centers of problems that were being caused by maintenance work.

Before his death, Nielsen told investigators that he had worked under stressful conditions on the night of the crash, because a colleague took a break and maintenance on the air traffic control system had affected monitoring and communications.

Prosecutors said neighboring control centers were not informed that the main telephone connection to Skyguide was out of order on the night of the incident. German officials tried to warn Nielsen, but could not reach him.

By the time Nielsen realized the problem, he gave the planes only 44 seconds' warning that they were getting too close to each other. He also mistakenly told the Russian plane to descend - sending it straight into the cargo jet.

All four will have to share court costs of 25,000 francs (US$20,700; euro15,200).