Medium Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Time Pressure; Fatigue; Confusion; Communication Breakdown; Workload
ATC Issue All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Became Reoriented
Procedure; Human Factors; Airport
We were proceeding direct to SAILZ on the RNAV Y 22L. ATC told us to turn right 20 degrees and 'join the final.' I turned right 20 degrees and Captain went to FMS to put in an intercept to the final approach segment which begins at YACHT. Quickly realized this did not make sense as intercepting the extended centerline of the runway would take us over downtown/inconsistent with this type of approach. Had ATC meant left 20 which would have us join the centerline of the runway south of downtown? Had ATC meant right 20 to join the INTERMEDIATE segment of the approach; a clearance I had never heard before in 10;000 hours of flying? Captain attempted to clarify but could not get a response. ATC then advised we were right of the intended course. They issued a heading to rejoin the approach which would have taken us head on into arriving traffic. We rejoined approach on our own and landed without incident.Recommend a speed adjustment instead of heading if the intent was to adjust spacing. No 'heading to join' when you're basically already on the published approach. I should have clarified before starting the turn. Unfamiliarity with the approach and approaching almost eight hours of block; I caught the confusion after I turned.
Air carrier First Officer reported a C90 TRACON Controller issued a 20 degree right turn while on the MDW RNAV Runway 22L Approach which would have placed the aircraft over the city. The crew realized the error; but ATC did not respond to clarify. ATC did finally issue an accurate vector to rejoin the approach.