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Air carrier captain reported an altitude deviation occurred following a clearance misunderstanding on arrival into mdw.
| Attributes | |
| ACN | 1551895 |
| Time | |
| Date | 201806 |
| Local Time Of Day | 1801-2400 |
| Place | |
| Locale Reference | MDW.Airport |
| State Reference | IL |
| Environment | |
| Light | Night |
| Aircraft 1 | |
| Make Model Name | Large Transport Low Wing 2 Turbojet Eng |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Initial Approach |
| Flight Plan | IFR |
| Person 1 | |
| Function | Pilot Not Flying Captain |
| Qualification | Flight Crew Air Transport Pilot (ATP) |
| Experience | Flight Crew Last 90 Days 440 Flight Crew Type 14333 |
| Events | |
| Anomaly | ATC Issue All Types Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy |
Narrative:
We were on the fissk 4 RNAV arrival proceeding direct to the halie waypoint at 6000' (halie restriction) and 250 knots (assigned). Approaching halie; chicago approach (128.2) asked if we could accept the RNAV (rnp) Y to runway 4R. We replied affirmative. Approach then then said proceed direct olcyk (IAF) for the RNAV (rnp) Y to 4R. Both the PF and PNF thought we were cleared for the RNAV (rnp) Y to 4R. The PF programmed the approach into the CDU. We reset the altitude window to 4000'; which was the crossing altitude for olcyk waypoint. We had flown past the halie waypoint at 6000' MSL and were eight miles from the olcyk IAF. LNAV/VNAV was already selected and the aircraft began its descent to cross olcyk at 4000' MSL. Chicago approach asked about our altitude passing 5500'. Pm replied we were descending to cross olcyk at 4000' MSL. Chicago approach said he did not clear us for the approach yet but we could descend to 4000' MSL. Chicago approach then cleared us for the RNAV (rnp) Y to 4R. There were no traffic conflicts and the remainder of the flight was uneventful.if you do not specifically hear the words 'expect' or 'cleared' for a certain procedure; ask the controller for clarification. When chicago approach said to proceed direct to olcyk 'for' the RNAV (rnp) Y to 4R; we honestly thought we were cleared for the approach. If approach would have stated cleared to olcyk 'expect' the RNAV (rnp) Y 4R we would not have descended.'
Original NASA ASRS Text
Title: Air carrier Captain reported an altitude deviation occurred following a clearance misunderstanding on arrival into MDW.
Narrative: We were on the FISSK 4 RNAV Arrival proceeding direct to the HALIE waypoint at 6000' (HALIE restriction) and 250 knots (assigned). Approaching HALIE; Chicago Approach (128.2) asked if we could accept the RNAV (RNP) Y to Runway 4R. We replied affirmative. Approach then then said proceed direct OLCYK (IAF) for the RNAV (RNP) Y to 4R. Both the PF and PNF thought we were cleared for the RNAV (RNP) Y to 4R. The PF programmed the approach into the CDU. We reset the altitude window to 4000'; which was the crossing altitude for OLCYK waypoint. We had flown past the HALIE waypoint at 6000' MSL and were eight miles from the OLCYK IAF. LNAV/VNAV was already selected and the aircraft began its descent to cross OLCYK at 4000' MSL. Chicago Approach asked about our altitude passing 5500'. PM replied we were descending to cross OLCYK at 4000' MSL. Chicago Approach said he did not clear us for the approach yet but we could descend to 4000' MSL. Chicago Approach then cleared us for the RNAV (RNP) Y to 4R. There were no traffic conflicts and the remainder of the flight was uneventful.If you do not specifically hear the words 'expect' or 'cleared' for a certain procedure; ask the Controller for clarification. When Chicago Approach said to proceed direct to OLCYK 'for' the RNAV (RNP) Y to 4R; we honestly thought we were cleared for the approach. If Approach would have stated cleared to OLCYK 'expect' the RNAV (RNP) Y 4R we would not have descended.'
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.