Date: 201207
Local time of day: 1201-1800
Location: ROA.Airport, VA
Aircraft: Regional Jet CL65; Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Descent
Airspace: Class C ROA
ATC / advisory: TRACON ROA
Reporter organization: Government
Reporter function: Approach; Departure
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Communication Breakdown; Confusion; Situational Awareness; Workload
Anomaly: ATC Issue All Types; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance
Detector: Person Air Traffic Control
Result: Air Traffic Control Issued New Clearance
Contributing factors: ATC Equipment / Nav Facility / Buildings; Human Factors; Procedure
Primary problem: Human Factors

Narrative: I was working the Roanoke East RADAR position with multiple inbounds and practice approaches to multiple runways. I was working a four plane sequence with a Gulfstream 4; a PA28; and then followed by a CRJ and a RV3 experimental when the incident occurred. I also had two inbounds into the airspace which were approaching my boundary; but did not see them due to our extremely poor RADAR coverage; so the notion of expecting coordination from the transferring facility (ZCW and GSO) was also in the back of my head. At the time of the incident I also had a C550 being vectored on a practice approach for the LDA to Runway 6 who I was also losing RADAR on due to our poor coverage. At the time of the incident I had a CRJ vectored for the visual approach Runway 34 with the RV3 searching for the traffic to follow. Air Carrier Y was already in contact with me and was requesting the visual approach for Runway 24. I told Air Carrier Y that I would check with the Tower and get back to them. Due to lack of thinking about the request; and the fact that most CRJs coming in from the West like Air Carrier Y all request Runway 6; I coordinated Air Carrier Y to land Runway 6 which was approved. I went back to Air Carrier Y and told them to 'proceed direct to the field and that they could expect the visual approach for Runway 6 and to descend and maintain 5;200' our MVA for the area. Air Carrier Y read back 'descend and maintain 2;500' and said thanks for working out the runways for them. During this time I also cleared the CRJ for the visual for Runway 34 and was vectoring the RV3 (VFR) direct to the airport and for him to keep his speed up so he could beat Air Carrier Y to the airport. I requested Air Carrier Y to reduce speed to 180 KTS which they replied they would as soon as they could. Also at this time I was coordinating a PA24 coming into my airspace from the northwest non-RADAR VFR at 5;600 and a DA40 coming in from the south non-RADAR at 4;500. I was also vectoring the C550 who was being vectored behind Air Carrier Y for the LDA Runway 6 final approach course. I realized that Air Carrier Y was not slowing down and that the sequence between them and the RV3 was not going to work. Also at this time I noticed that Air Carrier Y was descending through 4;000 and this is when I asked them if they had the field in sight which the replied they did. I also inquired as to why they had descended through 5;200; the altitude I assigned; and the replied I told them 2;500. I went back to Air Carrier Y and told them that I did not assign 2;500 and asked if they could maintain their own terrain and obstruction clearance to the airport which they replied that they could proceed to the airport VFR. Air Carrier Y did acknowledge that I may have given them 5;200 assigned but that they read back 2;500 which I did not catch obviously because I was pretty busy. Above all this was my mistake since I did not hear back the proper read back of 5;200 FT. I cannot stress enough however that in situations like this where the controller is vectoring aircraft to multiple runways to the same airport that the last thing they need to worry about is aircraft coming into their airspace non-RADAR identified solely because the RADAR coverage is so poor.




Synopsis: ROA Controller described a below MVA event during a busy/complex traffic period when an incorrect altitude read back went unnoticed. The reporter listed poor RADAR coverage as an added distraction contributing to the incident.