Two runway incursions this month occurring under the watch of the same developmental air traffic controller are under investigation by the US National Transportation Safety Board (NTSB).
The two incidents occurred in a span of roughly three weeks. On 3 June the developmental controller under the supervision of a certified controller cleared a Southwest Boeing 737 to taxi into position on the same runway where an ExpressJet Embraer ERJ-145 was cleared for takeoff.
NTSB says the ERJ crew saw the 737 and contacted the tower controller as the two aircraft came within 500ft of each other on runway 6L.
The same developmental controller on 26 June cleared another ExpressJet ERJ-145 flight to cross runway 24L at taxiway S to depart from runway 24R.
NTSB explains 19 seconds later the controller cleared a Dash 8 Q200 turboprop operated by CommutAir for takeoff on runway 24L. Again, the ExpressJet crew saw the departing Q200 and advised the tower controller their aircraft should not cross the runway. The CommutAir aircraft rotated roughly 1,500ft from where the ExpressJet ERJ was positioned.
In February of this year NTSB determined errors by controllers were probable causes of three previous near-misses at Chicago O'Hare International Airport, Fresno, California and LeHigh Valley International Airport in Pennsylvania.