Narrative:

While descending into phx on the eagul five; RNAV arrival; the pilot flying engaged VNAV when cleared to descend via the eagul five runway 26 transition. I read back the clearance and requested runway 25L for the transition and landing. The controller advised they were not able to offer that transition and we accepted the runway 26 transition. We had previously set up the arrival for the 25L transition.we then discussed the need to match the FMC programming to the clearance and I initiated the change to the runway 26 transition. After some confusion and questions when referring to the approach plate I was able to identify the proper transition in the FMC; select confirm and execute. This resulted in a discontinuity immediately after our next fix. I was able to clean up the discontinuity in a timely manner; however; I believe that as a result of the very complex sequence of crossing and speed restrictions the FMC then went through a recalculation of the computed path. We had already complied with an altitude restriction and speed restriction of 270 KTS at tiniz. Per the arrival we were to maintain 270 for approximately 30 more miles. After the reprogramming of the FMC and the recalculation of the path we received a scratch pad message of steep descent after eagul. We noted this and cleared the scratch pad.very soon after that message and prior to eagul the aircraft started a steep vpath descent. I believe we received a drag required message and the pilot pulled speed brakes to the flight detent because the power was at idle. In a few moments the speed quickly gained 20-25 KTS of airspeed. Almost immediately ATC gave us a turn off the arrival and a descent to a lower altitude. At the same time the pilot flying switched to vertical speed then level change to facilitate a reduction of airspeed. The controller asked us if we were maintaining 270 I briefly explained our speed excursion. From that point we received vectors to runway 25L for a normal approach and landing.if I were to re-run this arrival I would start by initially programming the runway transition that should be expected from ATC; not our preferred transition. This would have alleviated the recalculation; discontinuity and disruption to the calculated path on this very complex arrival. VNAV works well in the bbj but it is not tolerant of significant adjustments while descending on a predetermined path. It is also critical to remember that in vpath the aircraft will fly the path even if that means overspeed from a speed constraint. The constraint at eagul has a 5;000 ft altitude window; between FL230 and FL180. Making that a hard at crossing at FL180 could have moved the top of descent [TOD] further back and eliminated the need for the steep descent later in the flight. Things changed very quickly after the reprogramming of the FMC. Although it seemed like ATC intervened immediately; we should have changed vertical modes sooner to assure speed control and advised ATC of any difficulty meeting further constraints.

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Original NASA ASRS Text

Title: A B737-700 flight crew delayed re-programming their FMS for the EAGUL RNAV STAR Runway 26 transition vice their anticipated Runway 25L transition. The delay caused them to be too high to make the altitude restrictions while maintaining the airspeeds required. A deviation occurred and Approach Control intervened.

Narrative: While descending into PHX on the EAGUL FIVE; RNAV arrival; the pilot flying engaged VNAV when cleared to descend via the EAGUL FIVE Runway 26 transition. I read back the clearance and requested Runway 25L for the transition and landing. The Controller advised they were not able to offer that transition and we accepted the Runway 26 transition. We had previously set up the arrival for the 25L transition.We then discussed the need to match the FMC programming to the clearance and I initiated the change to the Runway 26 transition. After some confusion and questions when referring to the approach plate I was able to identify the proper transition in the FMC; select confirm and execute. This resulted in a discontinuity immediately after our next fix. I was able to clean up the discontinuity in a timely manner; however; I believe that as a result of the very complex sequence of crossing and speed restrictions the FMC then went through a recalculation of the computed path. We had already complied with an altitude restriction and speed restriction of 270 KTS at TINIZ. Per the arrival we were to maintain 270 for approximately 30 more miles. After the reprogramming of the FMC and the recalculation of the path we received a scratch pad message of STEEP DESCENT AFTER EAGUL. We noted this and cleared the scratch pad.Very soon after that message and prior to EAGUL the aircraft started a steep VPATH descent. I believe we received a drag required message and the pilot pulled speed brakes to the flight detent because the power was at idle. In a few moments the speed quickly gained 20-25 KTS of airspeed. Almost immediately ATC gave us a turn off the arrival and a descent to a lower altitude. At the same time the pilot flying switched to Vertical Speed then Level Change to facilitate a reduction of airspeed. The Controller asked us if we were maintaining 270 I briefly explained our speed excursion. From that point we received vectors to Runway 25L for a normal approach and landing.If I were to re-run this arrival I would start by initially programming the runway transition that should be expected from ATC; not our preferred transition. This would have alleviated the recalculation; discontinuity and disruption to the calculated path on this very complex arrival. VNAV works well in the BBJ but it is not tolerant of significant adjustments while descending on a predetermined path. It is also critical to remember that in VPATH the aircraft will fly the path even if that means overspeed from a speed constraint. The constraint at EAGUL has a 5;000 FT altitude window; between FL230 and FL180. Making that a hard at crossing at FL180 could have moved the Top Of Descent [TOD] further back and eliminated the need for the steep descent later in the flight. Things changed very quickly after the reprogramming of the FMC. Although it seemed like ATC intervened immediately; we should have changed vertical modes sooner to assure speed control and advised ATC of any difficulty meeting further constraints.

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.