Narrative:

While assisting another controller on the combined tar-D/left position; 4 arrivals were inbound from the northeast; two on the winng arrival and two on the pechy arrival. All aircraft needed to be blended in order to fit on the base leg for runway 26R. Aircraft X the lead aircraft on the pechy arrival was followed by aircraft Y; also on the pechy arrival. The spacing provided by center was more than the required 5 miles; but due to the overtake created by the fact that arrivals cross the airspace boundary at 280 knots 'descending via' the arrival procedure; this spacing rapidly collapsed to less than 5 miles. To mitigate the situation the controller issued aircraft Y 210 knots to increase spacing enough to give the final controller something to work with. Aircraft Y immediately responded that they would no longer be able to meet their altitude restrictions if they slowed; which would in turn result in an airspace violation of satellite and departure airspace.it is unacceptable to get aircraft at 280 knots on the base leg; with unpredictable compression (there is a 15 mile window in which the pilot can slow to 250 knots); especially when two base leg feeds are routinely fed to the same runway. Many times it is inappropriate to feed the final controller at a speed greater than 210 knots (our facility standard operating procedures specifically states that the final should not normally be fed at speeds greater than 210 knots); and aircraft 'descending via' are unable to make altitude restrictions if slowed beyond the 280/250 knot restrictions on the optimum profile descent (opd) arrival procedures.terminate the opd procedures at the A80 boundary and have all aircraft level at hard altitudes and in trail at 250 knots; especially when feeding dual base legs. Opd is manageable in a single stream scenario; but we are being fed dual stream opd arrivals from the northeast and the northwest. The complexity that this causes creates a huge safety risk. Simply slowing an aircraft to 210 knots to comply with our SOP results in the aircraft not being able to meet crossing restrictions; resulting in multiple airspace violations. Not to mention that the dual arrivals are routinely blended into a single base leg feed; requiring additional speed control and vectors. This procedure is not acceptable. It is my professional opinion that this operation is not safe and should be terminated immediately.

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Original NASA ASRS Text

Title: A80 Controller reported an example of why they feel their facility's new arrival routes and procedures are unsafe.

Narrative: While assisting another controller on the combined TAR-D/L position; 4 arrivals were inbound from the northeast; two on the WINNG arrival and two on the PECHY arrival. All aircraft needed to be blended in order to fit on the base leg for runway 26R. Aircraft X the lead aircraft on the PECHY arrival was followed by aircraft Y; also on the PECHY arrival. The spacing provided by Center was more than the required 5 miles; but due to the overtake created by the fact that arrivals cross the airspace boundary at 280 knots 'descending via' the arrival procedure; this spacing rapidly collapsed to less than 5 miles. To mitigate the situation the controller issued aircraft Y 210 knots to increase spacing enough to give the final controller something to work with. Aircraft Y immediately responded that they would no longer be able to meet their altitude restrictions if they slowed; which would in turn result in an airspace violation of satellite and departure airspace.It is unacceptable to get aircraft at 280 knots on the base leg; with unpredictable compression (there is a 15 mile window in which the pilot can slow to 250 knots); especially when two base leg feeds are routinely fed to the same runway. Many times it is inappropriate to feed the Final Controller at a speed greater than 210 knots (our facility Standard Operating Procedures specifically states that the final should not normally be fed at speeds greater than 210 knots); and aircraft 'descending via' are unable to make altitude restrictions if slowed beyond the 280/250 knot restrictions on the Optimum Profile Descent (OPD) arrival procedures.Terminate the OPD procedures at the A80 boundary and have all aircraft level at hard altitudes and in trail at 250 knots; especially when feeding dual base legs. OPD is manageable in a single stream scenario; but we are being fed dual stream OPD arrivals from the northeast and the northwest. The complexity that this causes creates a huge safety risk. Simply slowing an aircraft to 210 knots to comply with our SOP results in the aircraft not being able to meet crossing restrictions; resulting in multiple airspace violations. Not to mention that the dual arrivals are routinely blended into a single base leg feed; requiring additional speed control and vectors. This procedure is not acceptable. It is my professional opinion that this operation is not safe and should be terminated immediately.

Data retrieved from NASA's ASRS site 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.