Light Sport Aircraft
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 2
Conflict Airborne Conflict; Conflict Ground Conflict; Critical; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Returned To Departure Airport
Human Factors; Procedure
I had just taken position as Ground Controller and Controller in Charge. All runways were active and in use. Local Control Aircraft Y in LUAW (Line Up and Wait) on one runway; and also put Aircraft X in LUAW on an intersecting runway. Local Control then cleared Aircraft Y for takeoff. Two pilots transmitted at the same time. It was hard to understand. Local Control was also concerned with another operation and an aircraft 10 miles south requesting an Opposite Direction approach. Aircraft X took off without a clearance. Aircraft Y was airborne and through the intersection when Aircraft X was airborne and about 800 ft from the intersection both approximately the same altitude and climbing. Both Local Control and I were looking at the other runway areas when Aircraft X started take off roll without a clearance from LUAW. I alerted Local Control to Aircraft X taking off.This airport is a small VFR tower with a lot of training pilots. On occasions too numerous to count; pilots have not known or understood LUAW. My recommendation is to have a pilots meeting to discuss this practice and how to use it safely and properly. At this meeting; we could also talk to pilots about expectation bias and the importance of making sure you receive a clearance prior to taking action.
This was dual VFR instruction flight. The student is a finish up preparing in advance of his check ride. As the flight instructor I observed the student's check list usage from pre-flight through startup; taxi; run up. As the flight instructor I observed the student's radio operation and usage from ATIS; ground and tower operations. The student requested from ground the use of a different runway than on the ATIS as the planned flight was to be to the southwest from the airport.Following the run up; we switched to the tower frequency and monitored the frequency. There were several aircraft in the pattern including company aircraft. Our aircraft call sign was Aircraft X. My student called the Tower ready for takeoff. The Tower responded with Aircraft X line up and wait. The student confirmed line up and wait. Moments later; partial frequency congestion on the Tower frequency and incorrect volume setting on the radio; misunderstood; the takeoff clearance for [us]. Upon lifting off; observed a Cessna taking off on an intersecting runway and crossing ahead of our aircraft position. The Tower immediately called our aircraft and alerted us of the pilot deviation stating we were not cleared for takeoff. After takeoff; the student was having audio feedback and volume setting problems and turned off the audio panel twice resulting in no radio reception audio in either headset. I turned on the audio panel each time and instructed the student I have the aircraft. As instructor; I took over the controls and command of the aircraft; and stated we would land and taxi up to the base of the tower for the phone number. I received clearance from the tower to land followed by contact ground when the off runway. As instructor; I called ground control and they provided the local telephone number to call for follow up on the deviation.
ARR Tower Supervisor and a flight instructor reported that the student pilot took off after having only been cleared to line up and wait.