What happened
On July 5, 2012, at approximately 12:30 local time, a collision occurred at Cuatro Vientos Airport in Madrid involving two light aircraft. The first aircraft, a Cessna 172-N with registration EC-HIK, was positioned at the holding point for runway 28, performing engine tests prior to departure. At the same time, a Miles Falcon Six M-3C, registration EC-ACB, was taxiing from the military zone, crossing runway 2/28 to access the apron.
During the maneuver, the EC-ACB aircraft struck the EC-HIK aircraft. The right wingtip of the Miles Falcon initially impacted the right wing strut of the Cessna, followed by the propeller striking the Cessna's vertical stabilizer. The collision resulted in significant damage to the tail section of the EC-HIK, while the EC-ACB sustained minor damage to its propeller, right wing leading edge, and engine cowling. No injuries were reported for the occupants of either aircraft.
The investigation
The investigation examined the flight operations, pilot communications, and aircraft configurations. The pilot of the EC-ACB stated that after landing, they received authorization to backtrack and then cross runway 28. The pilot reported that they did not see the EC-HIK due to the extremely limited forward-right visibility inherent in the taildragger configuration of the Miles Falcon, especially with the pilot seated on the left side of the cockpit.
Investigators reviewed radio communications and found that while the tower had authorized the EC-ACB to cross the runway, controllers did not explicitly warn the pilot of the other aircraft waiting at the holding point. Furthermore, a discrepancy in radio frequencies was identified: the tower communicated with the EC-HIK on the ground frequency (121.80 MHz), while the EC-ACB was still monitoring the tower frequency (118.70 MHz). Consequently, the pilot of the EC-ACB was unable to hear the instructions or warnings being issued to the stationary aircraft.