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B737-800 first officer reported encountering wake turbulence in trail of an A321 on arrival into phx.
| Attributes | |
| ACN | 1703627 |
| Time | |
| Date | 201911 |
| Local Time Of Day | 1201-1800 |
| Place | |
| Locale Reference | ZAB.ARTCC |
| State Reference | NM |
| Aircraft 1 | |
| Make Model Name | B737-800 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Descent |
| Flight Plan | IFR |
| Aircraft 2 | |
| Make Model Name | A321 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Descent |
| Flight Plan | IFR |
| Person 1 | |
| Function | First Officer Pilot Not Flying |
| Qualification | Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine |
| Events | |
| Anomaly | Inflight Event / Encounter Loss Of Aircraft Control Inflight Event / Encounter Wake Vortex Encounter |
Narrative:
On arrival into phx; 6 miles in trail of an A321. Started getting violent rapid side loading; banking; and minor airspeed fluctuations. Normally; we go in and then out of wake turbulence before we have a chance to react; but this was sustained. I describe it as violent but not obscene; for example the bank changes; side loading and airspeed fluctuations were uncontrollable; but limited to +/-7 degrees of bank; and +/- 4 knots on the airspeed. No way to tell side loading. As we reentered it for the third time; we told ATC we needed a half mile offset. ATC complied; and then asked us if we could rejoin the arrival. When they asked; we hit another bit of wake turbulence and said no. They gave us vectors until final; where we were 4 and a half miles in trail again. We flew one dot high and then shifted to a normal glideslope and landed uneventfully. Captain remarked that he had not felt wake turbulence like that in years and felt like we were following a 757.close trail vectoring; and zero crosswind component. Winds were calm at altitude.it seems that spacing is going to a mileage restriction only; instead of a timing and distance based one. However; [with] airliners flying at 210-250 KIAS on the arrival; 6 miles can be as little as 1 minute; depending on tailwinds. Recommend going back to a combination of time and distance based restrictions for in trail spacing.
Original NASA ASRS Text
Title: B737-800 First Officer reported encountering wake turbulence in trail of an A321 on arrival into PHX.
Narrative: On arrival into PHX; 6 miles in trail of an A321. Started getting violent rapid side loading; banking; and minor airspeed fluctuations. Normally; we go in and then out of wake turbulence before we have a chance to react; but this was sustained. I describe it as violent but not obscene; for example the bank changes; side loading and airspeed fluctuations were uncontrollable; but limited to +/-7 degrees of bank; and +/- 4 knots on the airspeed. No way to tell side loading. As we reentered it for the third time; we told ATC we needed a half mile offset. ATC complied; and then asked us if we could rejoin the arrival. When they asked; we hit another bit of wake turbulence and said no. They gave us vectors until final; where we were 4 and a half miles in trail again. We flew one dot high and then shifted to a normal glideslope and landed uneventfully. Captain remarked that he had not felt wake turbulence like that in years and felt like we were following a 757.Close trail vectoring; and zero crosswind component. Winds were calm at altitude.It seems that spacing is going to a mileage restriction only; instead of a timing and distance based one. However; [with] airliners flying at 210-250 KIAS on the arrival; 6 miles can be as little as 1 minute; depending on tailwinds. Recommend going back to a combination of time and distance based restrictions for in trail spacing.
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.