A Polish airliner came within seconds of colliding with another plane near Heathrow because its pilots had such poor English that they could not understand basic instructions from air traffic controllers. The Lot Boeing 737, carrying 95 passengers and crew, wandered the skies for almost half an hour as the pilots struggled to identify their position. A controller had to instruct another aircraft to change direction to avoid a collision.

A document seen by The Times suggests that only 15 out of 800 Polish pilots flying internationally have passed the test for the required standard of English.

The two pilots in the Heathrow incident had to rely on directions after positioning instruments went blank because of a co-pilot’s error. They repeatedly failed to comply with instructions as they tried to return to Heathrow. On the final approach the Boeing appeared to be heading for the wrong runway, prompting a controller to order other aircraft to leave the area.

The incident, described in a report by the Air Accidents Investigation Branch (AAIB), highlights the risks associated with having so many foreign pilots with only rudimentary English using British airports. English is the international language of aviation but many countries failed to comply with the International Civil Aviation Organisation (ICAO) deadline of March this year for ensuring that their pilots were proficient in the language.

Poland has applied to the ICAO for an exemption until March 2011, the last possible date for compliance, after which pilots without the required level could be banned from international airspace. In a letter to the ICAO obtained by The Times, the Polish government’s civil aviation office suggests that only 15 pilots out of 800 Poles flying international routes have passed the appropriate English test.

The letter, sent on March 4, nine months after the Heathrow incident, states: “We haven’t had any accident caused by insufficient English level as well as [sic] we have not received any information from air traffic control agencies that Polish pilots were not able to communicate correctly. Therefore, potential risk of accident occurrence due to lack of English language proficiency is very improbable.”

That claim is contradicted by the AAIB’s investigation, which said: “The crew of Lot 282 were not able to communicate adequately the nature and extent of their problem.” The report added: “The commander, who was making the radio calls, was not able to understand some of the instructions.”

The AAIB found that an initial error by the co-pilot had been “compounded by the difficulty of obtaining information from the pilots because of their limited command of English”.

The Department for Transport confirmed that it had kept the Polish authorities informed of the investigation.

David Learmount, safety editor of Flight International magazine, said that it was very worrying that the pilots had not understood British controllers. “It could have been even worse if they had been trying to understand a French controller speaking to them in English,” he said.

“Countries which did not previously have many international pilots are now flooding the world with flights piloted by people who can’t speak English properly. For many pilots, learning English is much more difficult than learning to fly.”

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