Narrative:

An aero commander on a 180 degree vector climbing to 9;000 and a CRJ7 on 310 degree vector descending to 6;500. These vectors provided adequate lateral separation. I pointed the CRJ7 out to the aero commander and he said that he had him in sight when they were 4-5 miles apart on diverging courses. I then told the aero commander to 'maintain visual separation with the CRJ7; when able proceed direct ZZZ.' I left the CRJ7 on the same heading and [with] a clearance of 310 degrees descend and maintain 6;500. The aero commander read back something like 'roger we'll miss him going direct ZZZ.' I then told the aero commander 'read back visual separation instructions.' the aero commander then said something like 'affirmative; we won't hit him going direct ZZZ.' I had my 3 mile 'J' ring up and then edge of the CRJ7's target touched the 3 mile 'J' ring. The CRJ7 also reported the AC50 insight and the field. Come up with some better solution as to how the visual separation instruction acceptance is supposed to be done by the pilots. If the pilot says roger is that good enough? If they pilot says roger we won't hit him is that good enough? Do the pilots need to read back 'call sign will maintain visual separation with the ....' if the last sentence is the case; then the FAA needs to brief the pilots flying in the NAS. A lot of the times I won't clear somebody on course like I did in this situation in conjunction with maintain visual separation instructions because of the confusion with the rules.

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Original NASA ASRS Text

Title: TRACON Controller voiced concern regarding the 'Maintain Visual Separation' phraseology and the read back requirements from flight crews; indicating flight crews responses often do not comply with the latest FAA requirements.

Narrative: An Aero Commander on a 180 degree vector climbing to 9;000 and a CRJ7 on 310 degree vector descending to 6;500. These vectors provided adequate lateral separation. I pointed the CRJ7 out to the Aero Commander and he said that he had him in sight when they were 4-5 miles apart on diverging courses. I then told the Aero Commander to 'maintain visual separation with the CRJ7; when able proceed direct ZZZ.' I left the CRJ7 on the same heading and [with] a clearance of 310 degrees descend and maintain 6;500. The Aero Commander read back something like 'roger we'll miss him going direct ZZZ.' I then told the Aero Commander 'read back visual separation instructions.' The Aero Commander then said something like 'affirmative; we won't hit him going direct ZZZ.' I had my 3 mile 'J' ring up and then edge of the CRJ7's target touched the 3 mile 'J' Ring. The CRJ7 also reported the AC50 insight and the field. Come up with some better solution as to how the visual separation instruction acceptance is supposed to be done by the pilots. If the pilot says Roger is that good enough? If they pilot says Roger we won't hit him is that good enough? Do the pilots need to read back 'call sign will maintain visual separation with the ....' If the last sentence is the case; then the FAA needs to brief the pilots flying in the NAS. A lot of the times I won't clear somebody on course like I did in this situation in conjunction with maintain visual separation instructions because of the confusion with the rules.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.