B737 Undifferentiated or Other Model
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 180; Flight Crew Type 15000
Situational Awareness; Communication Breakdown
ATC Issue All Types; Conflict Airborne Conflict; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
General None Reported / Taken
Procedure
On the Arrival into ONT SoCal Approach assigned vectors to sequence behind a 747. We were vectored directly behind and above the preceding 747 for 26L when we were cleared for the visual approach to 26R. ATC advised to maintain visual separation. At that point; due to concerns of descending behind the heavy aircraft; I offset right of course and attempted to parallel the 747. My intention was to remain clear of the 747's wake vortices. As we continued the approach and began to converge with the other aircraft; ONT Tower issued clearance to S-turn to the right if necessary. At that point we were too close to the runway to make any effective maneuvers and still maintain a stabilized approach. We then received a 'Descend' RA and continued descending on the visual approach to 26R while the adjacent aircraft executed a climb and go-around from 26L. In retrospect I believe a better course of action would have been to discontinue the visual approach or ask for delay vectors to increase separation from the heavy aircraft. ATC should have issued more realistic vectors to sequence us further behind the 747.
Descending on the Arrival into ONT; SoCal Approach Control gave a maintain current HDG [instruction]. We visually acquired a 747 at our 12 o'clock position approximately 5 NMs. SoCal then gave us a right turn to a 140 HDG; then subsequently a 170 HDG that placed us at the 6 o'clock position of the 747 approximately 5 NMs behind. Once established on the 170 HDG; SoCal cleared us and the 747 visual approaches; 747 to Runway 26L and us to 26R and told us 'Caution wake turbulence and maintain visual separation with the 747'. The Captain did not want to be in a position to be at a 45 degree angle behind the 747; which would've increased the chances of getting into the wake of the 747; so as we were descending for the approach we received a descend RA and Aircraft Y executed a go-around for a climb RA. When we noticed that it would be challenging to do the approach and simultaneously staying out if the heavy aircraft's wake turbulence; should've asked the Controller for a vector or turn before starting the final portion of the approach.
B737 flight crew reported receiving an RA on approach.