CMA Controller described runway incursion event during a runway change procedure; reporter recommending additional runway access lighting equipment to provide pilots with increased information.
Synopsis
CMA Controller described runway incursion event during a runway change procedure; reporter recommending additional runway access lighting equipment to provide pilots with increased information.
Narrative
The event occurred during a change from Runway 8 to Runway 26. Traffic was steady and for about 10 minutes both Runway's 8 and 26 were used to depart aircraft that were already in the run-up for the respective runways. I was trying to maintain a heightened state of awareness at this time because of the runway change. Aircraft X was the last departure for Runway 8. The Local Control cleared Aircraft X for takeoff from Runway 8. I heard him reply cleared for takeoff. What I did not hear was Aircraft Y who had been told to stand by previously at Runway 26 also respond he was cleared for takeoff. After the Local Control cleared Aircraft X for departure off Runway 8 the Controller asked an inbound transponder only aircraft to say ALT because of traffic on the downwind departure. Then we noticed that Aircraft Y was across the hold line for Runway 26. The Local Control told Aircraft Y he was not cleared for takeoff and to make a 180 to exit the safety area and then she canceled takeoff clearance and told him to hold his position. When Aircraft Y exited the safety area the Local Control then cleared Aircraft X for departure from Runway 8. I think a way to avoid this in the future is to have a set of RACL (Runway Access Control Lights) lights at every entry point to a runway to visually tell the pilot he may access the runway. You could also hook up some type of motion sensor so that when something crosses the hold line the light returns to a RED X. That way he will have to have audible and visual conformation that he may enter the runway; not only for departure but also for crossing. A tape review indicated I was too loud in the background when the Local Controller was transmitting during the time leading up to the runway change. I will in the future try to lower my projection so as to not be background noise while others are transmitting.
Second reporter narrative
At the run up area I notified Ground Control; 'run up complete ready to taxi.' Ground Control responded; 'taxi to Runway 26; contact Tower.' I contacted Tower; 'Ready for takeoff; Right Cross Wind Departure.' At this point I thought I heard; 'cleared for takeoff Right Cross Wind Departure approved.' I crossed the hold short line and had reached the runway when I heard the Tower transmit for me to return to the run up area; which I proceeded to do and it was at that time I noted another aircraft about 4500 feet away facing as though to depart Runway 8 (I.E. opposite direction). At the run up area I received instructions to call a telephone number when able. At this point I decided to abort this flight and return to the hangar area and make the call. It was the Airport Supervisor who wanted to know my observations of the circumstances leading to the incursion. It appears after review that I was not cleared for takeoff; but the other aircraft was cleared for takeoff in the opposite direction also for a Right Cross Winds Departure. His aircraft call sign involved numbers close to mine. Also I had just changed headsets which were unfamiliar to me and with different fidelity; and I missed various transmissions. Several considerations also involved the use of opposing departure at the same time to wind changes at the airport favoring both ends of the runway. I believe I could have avoided any conflict by not changing headsets until having checked them more thoroughly before actually using them and also when any questions of perceived transmissions exist to take no action without repetition and clarification.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.