A report by the Air Accident Investigation Unit said there was no risk of collision, but there could have been “a more serious outcome”, if the timing of the take-offs had been different.
The incident occurred on May 23, 2017, when a 21-year-old student pilot, from England, on a solo flight in a Cessna 172 light aircraft, took off from the airport’s second runway without clearance.
He did so around the same time that another student pilot, accompanied by a flight instructor and in another Cessna 172, was cleared to take off from the airport’s main runway. The two runways intersect at right angles.
The AAIU report said the student pilot on a solo flight had received clearance to take up a taxiing position on the airport’s second runway.
Air accident investigators said he was not instructed to hold his position, as was standard procedure.
At the same time, the other Cessna was cleared for take-off. When the student pilot informed the airport tower he was “ready for departure”, an air-traffic controller twice replied: “Roger”.
The student pilot told AAIU investigators that he did not know if the use of “Roger” meant “understood” or “go ahead”.
The air-traffic controller expected the student pilot to hold his position, as no take-off clearance had been given.
The AAIU report said the student’s use of non-standard wording, in seeking confirmation that he was “ready for departure”, was the basis for a misunderstanding.
It also said the air-traffic controller could have avoided possible ambiguity by informing the student pilot to hold his position.
The event illustrated the necessity of clear communications between air-traffic controllers and pilots: “The use of standard radiotelephony terminology and greater awareness on the part of the student, by maintaining a good listening watch on the frequency, could have prevented the situation arising in the first instance.”
Cork Airport management and the flight school agreed to suspend the practice of solo student pilots using the secondary runway, pending a review.
The flight school also put in place further training in radio telecommunications for its students.