Flight Crew Air Transport Pilot (ATP)
Troubleshooting; Communication Breakdown; Confusion; Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Chart Or Publication; Human Factors; Procedure
Inbound to MSP we were cleared to descend via the MUSCL 3 RNAV Arrival; 30R Transition. We loaded the ILS 30R and selected the TRTEL transition. We flew this routing uneventfully and about the time we were turning final we were instructed to maintain visual separation with the parallel traffic; which we did. We were not made aware of any deviations during the flight and made an uneventful landing. A couple hours later I received a call from ATC and was informed of a pilot deviation and loss of minimum separation with another aircraft. He stated that after reaching TRTEL intersection he expected us to continue our present heading and NOT commence the turn to SOGGY; and because of that they lost minimum separation with traffic on the parallel (the aircraft we were told to maintain visual separation with).The approach plates were just changed effective January 5th to allow selecting a transition from the last fix on the STAR (TRTEL) to the selected ILS approach. Because we were told to descend via the arrival and given a specific runway for a transition we were under the impression that we were to fly the full transition to SOGGY after reaching TRTEL. After talking with ATC on the phone he explained there is confusion both with ATC and pilots for this particular issue; but that he expected us to just continue our present heading after reaching TRTEL; even though we had been cleared a specific runway transition and had not been assigned any radar vectors. He stated we should have only flown the transition to SOGGY if we had been cleared for the ILS PRIOR to reaching TRTEL. Two days ago on the radio; a pilot specifically asked about this and was told by ATC that if they are assigned the runway with the descend via clearance that they do expect us to fly the full transition. If ATC does not expect us to fly the full transition for the runway they assign to us during the descend via clearance and just to continue on our present heading after reaching the last fix on the arrival; that must be made clear when issuing the clearance or it must be made clear on the notes of the arrival itself. Clarification should be given to both ATC and pilots on what is expected.
The reported stated that they did not have clearance for the ILS approach and that TRTEL was his clearance limit. He advised that numerous pilots and controllers during this initial stage were confused if they were cleared for the approach or not. In this instance the reporter stated they were not cleared.
Nearly 2 hours after our arrival and release time I received a call from company crew support connecting my Captain to me. He informed me that he had been contacted by ATC about loss of separation on our arrival into MSP on the MUSCL3 30R Transition. As he explained it from his conversation with ATC; reaching TRTEL intersection we were expected to continue straight ahead. Having been given the 30R transition prior to TRTEL with ILS30R and ILS30L advertised on ATIS I had selected ILS30R from TRTEL in the FMS; and reaching TRTEL commenced the turn to SOGGY intersection. The NEW arrival effective 5JAN ends at TRTEL and states 'Expect RNAV; or ILS approach or Radar vectors to final; with no heading to continue. The NEW approach to ILS30R from TRTEL intersection is connected directly to the arrival. We were not given a heading to fly and had been cleared to 'descend via the MUSCL3 arrival 30R transition'. The Captain stated that ATC said our turn at TRTEL caused a loss of separation. We had been given traffic and advised traffic in sight and were then cleared for the ILS30R. The arrival and approach were normal with no deviations.Having been cleared to 'descend via MUSCL3 30R transition' I had selected the ILS30R from TRTEL intersection. Not receiving a heading or other direction from ATC; reaching TRTEL we commenced the turn to SOGGY on the ILS30R. We had been cleared to 4000' and were descending. After acknowledging traffic inbound for the parallel runway we were cleared for the ILS30R to cross SAMMZ at 4000'. On further examination of the MUSCL3 arrival chart; lacking radar vectors there is no charted indication or guidance to continue present heading (such as at DOLEE or COZZZ). There is clearly confusion between us and ATC over expected flight path reaching TRTEL. Without RADAR vectors; my understanding of the charted procedures is to continue the flight path from TRTEL on the 30R transition (make the turn via the connection to SOGGY) but NOT descend until cleared for the approach. This is what we did.Clarification is needed of the expected flight path. For example; in KDEN if flying the KIPPR4 arrival; 16L transition; reaching KIPPR the flight path continues to HAYLY; this is the transition; KIPPR is the IAF. Descent does not commence until cleared for the ILS16L OR otherwise directed by ATC. This is the same procedure as the NEW charts in MSP; yet ATC expects something different; and I am unsure of WHAT; as that is not information provided. This is a new procedure in MSP and extreme caution and awareness is needed by ATC and pilots.
CRJ-200 flight crew reported being assigned the MUSCL3 Arrival Runway 30R transition at MSP. Later he was made aware that a loss of separation occurred while turning final. The Controller explained he was expected to maintain heading after the last point on the arrival since he had not been cleared for the ILS.