Narrative:

As the controller in charge; I was providing general supervision to the entire operation in the tower cab. A gulfstream III (large category aircraft); was on an ILS runway 16R approach from the north. A cessna 172 (small category aircraft); is on a VOR-a approach from the southwest. TRACON cpc coordinated with the tower to provide visual separation between gulfstream III and cessna 172. The tower accepted visual separation responsibility. Although the tower provided visual separation with the two IFR aircraft inbound for IFR separation; the tower controller did not and could not provide visual separation when wake turbulence was involved. Per jo 7110.65U 7-2-1 a 2. The tower must not provide visual separation between aircraft when wake turbulence separation is required. When the gulfstream III was over the landing threshold; the cessna 172 was 1.93 miles in trail on final. In complete honesty; I was not aware of the wake turbulence visual separation requirements in reference to wake turbulence; since we can not and do not provide this separation. When asked and as able; we always accommodate and accept visual separation (when wake turbulence is not involved). In asking the tower working LC1; they had the same lack of awareness. That also seemed to be the general consensus of most cpc's at our facility. Even though this separation is prescribed in the 7110.65; it is the TRACON's responsibility and we cannot provide it. However; as a recommendation; if tower personnel are briefed with a refresher; perhaps they will be more vigilant with this separation and can send an aircraft around or notify the TRACON ahead of time for alternate instructions.

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Original NASA ASRS Text

Title: Tower Controller described a request from the parent Approach Control requesting that visual separation be applied not realizing that 'wake turbulence' was involved and Tower was unable to provide this type of visual separation.

Narrative: As the CIC; I was providing general supervision to the entire operation in the Tower cab. A Gulfstream III (large category aircraft); was on an ILS Runway 16R approach from the North. A Cessna 172 (small category aircraft); is on a VOR-A approach from the Southwest. TRACON CPC coordinated with the Tower to provide visual separation between Gulfstream III and Cessna 172. The Tower accepted visual separation responsibility. Although the Tower provided visual separation with the two IFR aircraft inbound for IFR separation; the Tower Controller did not and could not provide visual separation when wake turbulence was involved. Per JO 7110.65U 7-2-1 a 2. The Tower must not provide visual separation between aircraft when wake turbulence separation is required. When the Gulfstream III was over the landing threshold; the Cessna 172 was 1.93 miles in trail on final. In complete honesty; I was not aware of the wake turbulence visual separation requirements in reference to wake turbulence; since we can not and do not provide this separation. When asked and as able; we always accommodate and accept visual separation (when wake turbulence is not involved). In asking the Tower working LC1; they had the same lack of awareness. That also seemed to be the general consensus of most CPC's at our facility. Even though this separation is prescribed in the 7110.65; it is the TRACON's responsibility and we cannot provide it. However; as a recommendation; if Tower personnel are briefed with a refresher; perhaps they will be more vigilant with this separation and can send an aircraft around or notify the TRACON ahead of time for alternate instructions.

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.