MD-80 Series (DC-9-80) Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Confusion; Situational Awareness; Time Pressure; Communication Breakdown; Human-Machine Interface; Distraction; Workload
ATC Issue All Types; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued Advisory / Alert; Flight Crew Returned To Clearance
Chart Or Publication; Human Factors; Procedure; Aircraft; Weather
On the TRUPS RNAV STAR into DCA in an MD-80 we were in moderate icing conditions with a tailwind. The speed brakes were full aft in a max effort to comply with the crossings and speeds on the arrival. Approaching TRUPS we understood the Controller to tell us to maintain 11;000 feet and 290 KTS until TRUPS. Then; instead of tracking to LETZZ to cross at 8;000 feet; we were cleared TRUPS direct to RLLLL to continue on the arrival. After passing TRUPS we slow down to be at 250 KTS to pass through 10;000 feet to cross RLLLL at 6;000 feet. As we are slowing through about 260 KTS and approximately 10;600 feet the Controller says 'What did I tell you?' And he asked us about three times; 'What did I tell you?' For that question; we had no answer; but we responded that we were slowing to 250 KTS to descend below 10;000 feet on the arrival. He then explained we were cleared to maintain 11;000 feet and 290 KTS. We start to climb and he said 'Never mind; you are cleared to 6;000 feet.' We do not remember reading back such a clearance as he describes. He very well could have given us that clearance; but we did not comprehend it nor did we acknowledge it as he intended us to fly it.The TRUPS Arrival in to DCA is a difficult approach and on an MD-80 it requires both crew members' full attention. It is difficult to switch gears when [what you are already doing] is taking max effort. When the Controller changed three parameters of the arrival with one clearance; [his intent was; apparently;] misunderstood. Everything happened very quickly. The work load is too much at that time to process and implement three changes without making sure the crew understands exactly what the Controller wants. My first suggestion would be not to allow the [MD-80 to fly the] TRUPS arrival. If the TRUPS stays; my second suggestion would be; if the controller needs to make changes to the arrival; preface the clearance with; 'disregard speed and altitude on the arrival; I now need to you to maintain 11;000 feet and 290 KTS until further advised.' The clearance needs to be very direct; in reference to the [published constraints of the] arrival because; up until that moment; we are [at max workload to do] what we had briefed and planned in order to fly it as published. Additionally; the controller needs to be aware of the workload and ensure the aircrew reads back the clearance and understand it as he intends it to be flown.
The TRUPS Arrival into DCA is a complicated and labor intensive procedure. Compliance is exasperated when tailwinds and icing conditions exist. Both of these circumstances existed during this event. When the 'descend via' instruction is issued; and multiple modifications to the procedure are subsequently instructed; exact and correct responses must be confirmed by ATC. I recommend:1. Modify the TRUPS STAR to reduce the 12 listed [constrained waypoints] to something more manageable. 2. Insure all clearances [modifying the STAR] are correctly read back; particularly after a 'descend via' clearance has been issued. 3. Eliminate all non clearance related communication issued by ATC. In this example; many 'what did I tell you' queries were asked by ATC when one instructional communication would have been more appropriate and rectified the error. Not only is this type of communication unprofessional; it also lends itself to defensive and distractive responses during a critical phase of flight. I further recommend a review of the audio track of this exchange for critique and debrief.
When ATC issued vectors; direct routings and modified altitude clearances subsequent to a prior 'descend via' the TRUPS RNAV STAR to DCA the flight crew of an S90 was confused and attempted to comply with lower charted restraints rather than level at 11;000 feet as intended by ATC. An apparently frustrated Approach Controller directed several repetitive and inappropriate inquiries at the flight crew as a result.