Amateur/Home Built/Experimental
Air Traffic Control Fully Certified
Communication Breakdown; Distraction; Training / Qualification
Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Returned To Clearance; Flight Crew Took Evasive Action
Airspace Structure; Procedure; Human Factors
Training in progress. Trainee gave pilot a descent from 050 to 040; pilot read back 040. Trainee observed aircraft Mode C at 030 in 036 MVA. Trainee issued a low altitude alert and climbed the aircraft to 040. Pilot stated he was assigned 030; trainee replied and told pilot he was assigned 040. 040 was verified and read back by the pilot. STARS equipment did not give a low altitude alert. Trainee or Instructor could have recognized the altitude discrepancy sooner. Otherwise; great low altitude alert and recovery was given by trainee.
TRACON Controller reported that an aircraft descended below their assigned altitude and caused the controller to issue an altitude alert.