B737-800
Air Traffic Control Fully Certified
Inflight Event / Encounter Wake Vortex Encounter
Air Traffic Control Issued New Clearance; Air Traffic Control Separated Traffic; Flight Crew Took Evasive Action; Flight Crew Requested ATC Assistance / Clarification
Environment - Non Weather Related; Procedure
I was working sector 90/47combined. A B737-800 had checked on at FL340 after being descended by sector 80 and I gave them descend via into PHX on the PINNG1. About 10-12 miles in trail; an A319; checked on also at FL340; just leveled; also going to PHX; having been descended by sector 80. The pilot keyed up and asked for lower. I gave them FL300. I had no ride reports; most everything was reporting smooth. The closest weather was well to the north; about 60 miles away. When the pilot had keyed up; I heard a warning tone in the background so I thought maybe something was going on. The pilot then told me they had received moderate turbulence about 60 seconds previous. I told them I had no ride reports and asked the preceding aircraft; the B737-800 at FL340; who said it was smooth. I told the A319 that they were following a B738 and that they might have gotten the wake off them. The pilot confirmed that a minute or so later; and then informed me that the aircraft had rolled. I told the supervisor. The A319 asked if they could start down and stay 2000 or so feet underneath the B737-800; I told him they were both going to PHX on the arrival; so I offered to vector the aircraft out to get more space. At this point; they were about 13 miles in trail and the pilot took me up on the offer. At the point where I had 15 miles or so; I told the pilot; but he wanted to stay on the vector for another 1.5 minutes. I turned them back at about 17-18 miles and ended up with just over 18. The pilot was obviously rattled. I asked the B737-800 pilot if they were heavier than normal; but he told me no.I had three other wake events recently. I had an ERJ175 the other day being vectored behind a B777 into PHX who asked for an additional vector to stay at least 12 miles behind the aircraft. Granted they were following a heavy; but I'm not sure if controllers in enroute understand the impact of using less than 8-9 miles of separation behind a heavy; especially the 'larger' heavies like the B777 and B748s (and; of course; A380). About a month or so ago (maybe more) I had an ERJ175 behind an A321 at FL350 behind vectored to stay behind. About 8 miles back they got into the wake and complained about it. I had a B737 on the HYDRR arrival into PHX about 12 miles behind company B738 and got moderate turbulence. Usually in the absence of adverse and/or forecasted adverse ride reports; that is almost always a wake encounter. I also had a conversation with a pilot friend of mine who expressed concern to me about the number of wake events they are having in enroute. The increased accuracy of both RNAV and RNP has increased the risk of these events considerably.Recommendation: I've reported the wake problems we've been having in enroute before. In conversations with the enroute representative; it is known about the wake problems with the A321 and B738/9 (as well as MAX I'm sure); but that information has not really trickled down to the controller ranks. This is somewhat disconcerting to me. I don't know that the status quo of 1000 feet /5-mile in enroute is sufficient anymore. Terminal has considerable wake turbulence training; and the separation standard accounts for much of this (though I don't know much about RECAT). The wake problems we are having in enroute should necessitate training as well as consideration of our enroute separation standard. At a minimum; maybe we should start telling the aircraft when the preceding aircraft is a heavy; B738/9 or A321? Maybe we need an increased standard beyond 5 miles when following a preceding aircraft at the same altitude.
ZAB Enroute Controller reported seeing a number of wake turbulence events recently; and questioned current in-trail techniques.