Two passenger planes missed each other in the Kenyan airspace by a minute last week, averting what would have been one of the worlds worst aviation accidents.

The near-collision, at Naivasha, 100 kilometres west of Nairobi, was prevented when the pilot of one of the planes made a sudden climb to avoid the oncoming flight after receiving a warning from the inflight traffic collision system.

From revelations by the East African, the incident, involving an Ethiopian Airways plane and an Italian leisure airline flight, has become a major point of discussion in aviation circles, leading to a blame game between Kenya and Ethiopia.

Flight paths

On Wednesday August 29, the Ethiopian Airlines flight number ET858, a Boeing 737-800, registration number ET-ASJ left Johannesburg for Addis Ababa at 2100 hours.

On the same day at 18:00 hours, an Italian leisure airline Neos Boeing 767-306R flight number NOS252, registration I-NDOF had left the Italian city of Verona heading to Zanzibar. Its flight time was eight hours before it made its first landing in Zanzibar.

At 00:49 hours, both aircraft were in Kenyan airspace, at the same altitude, with the Italian aircraft having entered from the Ethiopian airspace, while the Ethiopian Airlines from the Tanzania airspace. They were flying towards each other.

The Traffic Collision Avoidance System Resolution Advisory alerted the Ethiopian airline crew about the impending mid-air collision and the pilot climbed to 38,000 feet in just one minute (at 00:50 hrs). He maintained the altitude for five minutes, avoiding the collision.

The TCAS is built in planes to monitor the airspace around an aircraft for other aircraft equipped with an equivalent active transponder. The system, which is independent of air traffic control, warns pilots of the presence of other aircraft. Kenya's air traffic controllers seem to be blaming the incident on a strike by Ethiopian air traffic controllers.

Serious breach

“The Italian airliner approached and entered the Kenyan airspace from the Westside using 370L but it wasn’t informed by the Ethiopian air control that an ET flight was also using the same altitude East side as it crossed over Kenya heading to Addis. This was a serious breach of safety,” a source in the Kenyan aviation sector told The EastAfrican.

The source said the Ethiopian air traffic controllers had begun their strike four days prior to the near-crash, and failed to honour the co-ordination procedures agreed between Nairobi and Addis Ababa on air traffic navigation and management.

The day after the near mishap, the Kenya Air Traffic Controllers’ Association warned that flights going into and out of the Addis Ababa airspace were not safe.