The Czech Republic air force pilot of a Saab Gripen came within an estimated 10m (33ft) of hitting a target-towing Bombardier Learjet 35 with nine cannon rounds after operating procedures broke down during a live-fire exercise,

"During the first attack the crew of Target 03 heard a clattering sound that they had never heard before." As the hit indicator on the aircraft's spare target was switched off for the sortie, it was only after landing that the Learjet crew discovered that this had been hit nine times in its rear half, "with a good close grouping".

the pilot of single-seat aircraft 9235 mistakenly fired on the spare target using his 27mm Mauser BK27 internal cannon, after first checking with his wing man. "The Czech pilots discussed the target configuration in Czech on their squadron frequency. They considered that the target was close to the towing aircraft, but as they had been cleared to attack, they assumed that they had permission to fire," the report says.

The Czech pilots - who had little or no previous experience of live gun firing against an airborne target - also received confusing briefing instructions and were not told that the spare target would be visible during their attack runs, it adds.

Saab was meanwhile criticised for not having an established standard operating procedure for towing targets during live gun firing. "The Saab SFO Learjet 35 is not equipped in such a way that live gun firing from other aircraft at a towed target could be carried out in a manner that is consistent with flight safety," the report says. "The crew have no possibility to see the target or attacking aircraft in their rear sector, so they cannot order [an] attacking aircraft to hold its fire if the attack profile is abnormal."

The board recommends that the Swedish military review its regulations for the operation of "foreign governmental aviation on Swedish territory", and has also called on Saab to improve its ability to monitor an attacking aircraft under future such conditions.