Commercial Fixed Wing
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 1.3
Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Air Traffic Control Separated Traffic
Aircraft; Manuals; Procedure
Working Departure sector. Gorgeous VMC. The SOP allows ATCT to launch successive departures utilizing pilot provided visual separation. The ATCT must modify the secondary scratchpad in the STARS data-tag to advise the TRACON that pilot provided visual separation is being used. However; in this case the first aircraft is [a specific airbus model] and that type of aircraft is notorious for climbing out much slower than most other aircraft.According to the FALCON replay; the trailing [B737] is 1.55NM behind the [airbus] with a 60 knot overtake. I restricted the [B737] to 230 knots and requested the [airbus] increase to 250 knots as soon as possible. Despite those efforts the situation continued to compress. While I was aware pilot provided visual separation was being utilized; in my judgement the situation had become unsafe and I decided to break our noise abatement procedures and initiate an early eastbound turn for the [B737]. After initiating the turn I made the supervisor aware of the situation. Both aircraft subsequently continued their departures without further incident.This is a common problem that we experience with the [airbus type] departures. I do not know why this specific aircraft type climbs out so differently; but it is common knowledge at the TRACON. I would propose that this situation could be corrected by changing the LOA to exclude [this aircraft type] departures from the provision allowing the use of pilot provided visual separation between successive departures. If ATCT had utilized the standard 3-5 mile in-trail spacing that would have been required during; this event would have been avoided.
An Airbus aircraft climbing out at much slower speeds than other similar aircraft could cause a loss of required separation.