Commercial Fixed Wing
Flight Crew Last 90 Days 43
Workload; Distraction; Communication Breakdown; Confusion
ATC Issue All Types; Deviation - Altitude Overshoot; Deviation - Speed All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural FAR
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Requested ATC Assistance / Clarification
Procedure; Aircraft; Human Factors
Descending into SDF on the MAUDD RNAV STAR we had planned and briefed an approach to 35L. Center assigned cross DARBY at 11;000 and 250 KTS and handed us off to LEX Approach. LEX removed the speed restriction; cleared us to descend to 10;000 and handed us off to SDF Approach. They cleared us below 10;000 and assigned Runway 35R. Just prior to DARBY during the runway change process; I lateraled off DARBY and selected the new runway; but the RNAV arrival dropped out. We were at 305 KTS still above 10;000 and I expected that we would be able to reload the arrival prior to reaching DARBY; however; we were unable to accomplish this. It took two tries to reload the arrival. The successful reload was accomplished by loading MAUDD Intersection and building off that. Just prior to DARBY the First Officer called ATC and asked for a 315 heading since we were accomplishing the runway change. ATC was confused stating they had not issued a runway change. After a couple of transmissions they assigned a 290 heading. About this time I told the pilot flying to watch the speed; he was at about 9;600 descending at 305 KTS. He leveled off and decelerated prior to continuing descent to 4;000. About this time we got the arrival rebuilt and asked ATC if they wanted us to rejoin the arrival; they responded with vectors to the ILS 35R. The cause of this event was the 'Runway change' that we received just prior to DARBY. ATC does not look at this as a runway change. We need this information earlier than we currently get it. We have to talk to LEX Approach we get three altimeter changes (Center with descent clearance; LEX after handoff and SDF on handoff.) This just adds to an already busy workload. There is an at or above 10;000 crossing at MAUDD; Center assigned DARBY at 11;000 and 250 then after the handoff LEX assigned 10;000 with no speed restriction. They then cleared us down to 7;000 (I think; definitely below 10;000). This made me think of the restriction on the arrival it is a hard altitude at or above 10;000; I believe that the clearance [to a hard lower altitude] overrides the altitude on the arrival but it made me think about it. On top of not using the altitudes published on the arrivals the controllers also are late assigning a runway; if we must speak to LEX they should be giving us the expected runway or else the arrivals need to be runway specific. Getting the runway assignment approaching a turn on the arrival is very problematic on these new arrivals. ATC should allow the arrivals to be used as published with timely runway assignments or not use these RNAV arrivals.
[Narrative 2 contained no additional information.]
When the flight crew programmed a runway change from 35L to 35R as they approached DARBY on the MAUDD RNAV STAR to SDF the route dropped out of the FMC and it was necessary to 'rebuild' the route. The distraction and workload that resulted contributed to minor altitude and track deviations.