Light Transport
Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Last 90 Days 88; Flight Crew Total 11000; Flight Crew Type 3900
Confusion; Communication Breakdown; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued Advisory / Alert; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action
Procedure; Human Factors
While on a shallow VMC descent into the LBE area; Johnstown Approach advised us of King Air traffic at our 1-2 o'clock position. We advised 'traffic in sight' and the Controller responded with 'maintain visual separation.' Continuing our descent; the light twin also advised 'traffic in sight;' and again the Controller responded with 'maintain visual separation on the jet.' While monitoring our TCAS display; I recognized the necessity to increase our rate of descent; but the system still barked an advisory command. It was evident that we were on a converging course; something NOT conveyed to us by the Controller. Accepting the separation command; we essentially exonerated the Controller of all responsibility. It would have been nice to know initially the degree of threat the light twin actually was. In the future I will NOT call traffic in sight descending into this area; relinquishing my protection. I'm surprised the Controller did not advise the degree of threat posed by the twin.
Both aircraft were issued 'maintain visual separation' and both aircraft accepted. Never did Johnstown mention that the aircraft would be converging. As we descended; it became apparent that we were converging with the twin. The PF acknowledged this and increased his descent rate. As the courses converged; the twin asked Johnstown if the jet was descending and Johnstown acknowledged that we were descending. At some point; the TCAS sounded and was giving RA instructions. The PF continued his descent knowing that there was no substantial risk of collision and the twin was in visual contact the whole time.
A Corporate jet crew and light twin pilot both asked JST Approach about mutual traffic and were told to maintain visual but neither was advised of their converging tracks which resulted in the jet crew taking evasive action.