Super King Air 200
Air Traffic Control Fully Certified
Communication Breakdown; Situational Awareness
ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance
Procedure; Human Factors
I was providing on-the-job training on South RADAR. I was discussing traffic flows with the North RADAR Controller and my trainee. A BE20 checked on and the trainee told him to fly present heading and to descend and maintain 8;000. The pilot had some confusion in his read back and said to maintain 6;000. The error wasn't caught until the BE20 was through 7;500 in an 8;000 MVA and was told to climb and maintain 8;000 immediately. Pay closer attention to the read backs. I should have been watching my trainee more closely; even on very light traffic. Use more caution when a runway assignment can sound like an altitude assignment.
I was CPC-IT on South RADAR combined with Final West; Southeast RADAR; and South Hand-Off. I was discussing techniques with my trainer and the North RADAR Controller. A BE20 checked in [and] I told the BE20 to fly present heading vector to the visual [approach]; descend and maintain eight thousand. The BE20 read back fly present heading and with some confusion read back descend to 6;000. I caught the error; not at time of read back; but as the BE20 was descending through 7;500 in an 8;000 MVA and instructed the BE20 to climb and maintain 8;000 immediately. The BE20 climbed to 8;000. Pay closer attention to hear back read back as this is a major contributor to the breakdown of ATC communication. Use 'Niner' Thousand as an intermediate altitude in reference to its unique sounding nature as well as buffer with mountainous terrain/MVA.
TRACON Controller providing OJT failed to note an incorrect read back that resulted in a below MVA event.