Narrative:

Flying into lax on the RIIVR3 pgs transition; we were in the mid-thirties on our arrival into lax and I heard an airbus super check in on the frequency at FL400. Shortly after that we were vectored for spacing and I spotted the airbus above us to the north. It was descending on TCAS as it was heading westbound and we were heading northwest on the vector. I asked lax center what our sequencing was; and he came back saying we were being vectored behind an airbus 380 super and that he would be turning us back in a couple minutes. Shortly after that he told us to turn and proceed direct to gramm intersection on the arrival. At that time I had the A380 in sight. We were being cleared to proceed directly behind the A380 and he was still above us. Aware that it would put us at risk of flying into his wake turbulence; I asked to stay on the northwest bound vector to stay clear of the A380 track and worked to stay clear of his wake until he was below us on the way into gramm intersection. That request was approved and I was told when clear I could proceed direct to gramm. We were also holding a slower speed assigned by center for spacing. Once I was ready to turn back to join the arrival; we were told to accelerate to 300 knots plus. This was just going to bring us back closer to the A380 as we sped up and he started slowing down for the crossing restriction over gramm at 280 knots. I could see on the TCAS that we were above the A380 descent path up to the gramm waypoint; but as we passed through about 18000 feet we encountered the A380 wake anyway. Everything happened very quickly and either the auto-pilot disconnected on its own or I disengaged it as I tried to control the pitch and rolling motion that occurred once we connected with the wake vortex. The rolling moment was extreme and the jet seemed to wallow as I added power and attempted to climb up and out of the wake vortex. After several seconds we were back in clean air; and I told center what had happened and that I wanted a turn off of the arrival to get more spacing on the A380 super. We turned southwest and got separation and then were cleared back to join the arrival. I asked where the A380 was now and if he was on the 25L transition. ATC told us it was 15 miles ahead and was on the north runway transition for runway 24R. We were going to 25L. After landing the aircraft was taken out of service for an aircraft vibration/severe turbulence encounter. I was also informed by the flight attendants that a couple of them had actually gotten thrown into the laps of passengers. They described the fact that it felt like the aircraft was going to roll upside down. No injuries were reported from the flight attendants or passengers that I know about. [Caused by] separation issues with a very large aircraft enroute to lax. Inadequate knowledge or heavy workload of ATC controller leading to a clearance that would have placed us in-trail of this A380 super as it descended through our altitude directly in front of us. Aircrew intervention placed us away from this super aircraft instead of being right behind it initially. ATC directed us to speed up to close the gap in spacing behind the super that put us in the zone to encounter its wake on the arrival. Wake turbulence encounter passing approximately 18000 ft descending on the RNAV arrival due to proximity to the A380 aircraft and its descent profile. This resulted in a strong to extreme wake turbulence event.take away and suggestions to keep this from happening again:ATC and aircrew training to ensure we are aware of the significance of not only in-trail separation from heavy or super category aircraft; but also the factual and aerodynamic characteristics of wake vortices; and how they manifest themselves and move through the air. With an average descent rate of 500 ft per minute; wakes do not remain static. With increasing changes in configuration wakes become stronger. With tailwinds and crosswinds; the wake can linger longer in certain places which can affect an in-trail aircraft both on the initial arrival and descent as well as final approach. Strong emphasis how to vector other aircraft in behind heavy or super aircraft; especially when the heavy or super aircraft is above and will be descending through the trailing aircraft's flight path. This is potentially very dangerous for the reasons that led up to this report. Though I was aware and asked questions and tried to mitigate the threat before it could create a hazard to my flight; other aircrew may not even have had a clue what was about to happen. Vertical and lateral in-trail separation needs to be greater following these super aircraft especially with the constraints and crossing altitudes we experience on most RNAV arrivals. With at or above crossings; the potential exists that the preceding super aircraft could be above the path of the following in-trail aircraft. Much like being a dot high on the glide path to final; the in-trail aircraft then faces the risk of encountering the wake of the preceding heavy or super during many phases of the RNAV descent profile. I believe that is what happened to us during our encounter. ATC; both center and approach control; need to also always inform following aircraft within a set range that they are crossing or following the path of a heavy or super aircraft. Currently that only seems to occur in the approach sector of flight into the airports we serve. One other take away from this event. At each recurrent; we have the requirement and opportunity to do upset recoveries. Sometimes this is set up as though from a wake turbulence encounter following a heavy aircraft. I am grateful for that training and; along with the awareness of the possibility of a wake encounter; I believe that this training helped to contribute to the successful recovery following this wake turbulence event.

Google
 

Original NASA ASRS Text

Title: B737 flight crew reported a 'severe' wake turbulence encounter on arrival into LAX 15 miles in trail of an A380.

Narrative: Flying into LAX on the RIIVR3 PGS Transition; we were in the mid-thirties on our arrival into LAX and I heard an Airbus Super check in on the frequency at FL400. Shortly after that we were vectored for spacing and I spotted the Airbus above us to the north. It was descending on TCAS as it was heading westbound and we were heading northwest on the vector. I asked LAX Center what our sequencing was; and he came back saying we were being vectored behind an Airbus 380 Super and that he would be turning us back in a couple minutes. Shortly after that he told us to turn and proceed direct to GRAMM Intersection on the arrival. At that time I had the A380 in sight. We were being cleared to proceed directly behind the A380 and he was still above us. Aware that it would put us at risk of flying into his wake turbulence; I asked to stay on the northwest bound vector to stay clear of the A380 track and worked to stay clear of his wake until he was below us on the way into GRAMM Intersection. That request was approved and I was told when clear I could proceed direct to GRAMM. We were also holding a slower speed assigned by Center for spacing. Once I was ready to turn back to join the arrival; we were told to accelerate to 300 Knots plus. This was just going to bring us back closer to the A380 as we sped up and he started slowing down for the crossing restriction over GRAMM at 280 knots. I could see on the TCAS that we were above the A380 descent path up to the GRAMM waypoint; but as we passed through about 18000 feet we encountered the A380 wake anyway. Everything happened very quickly and either the auto-pilot disconnected on its own or I disengaged it as I tried to control the pitch and rolling motion that occurred once we connected with the wake vortex. The rolling moment was extreme and the jet seemed to wallow as I added power and attempted to climb up and out of the wake vortex. After several seconds we were back in clean air; and I told Center what had happened and that I wanted a turn off of the arrival to get more spacing on the A380 Super. We turned southwest and got separation and then were cleared back to join the arrival. I asked where the A380 was now and if he was on the 25L transition. ATC told us it was 15 miles ahead and was on the North Runway transition for Runway 24R. We were going to 25L. After landing the aircraft was taken out of service for an Aircraft Vibration/Severe turbulence encounter. I was also informed by the Flight Attendants that a couple of them had actually gotten thrown into the laps of passengers. They described the fact that it felt like the aircraft was going to roll upside down. No injuries were reported from the Flight Attendants or passengers that I know about. [Caused by] separation issues with a very large aircraft enroute to LAX. Inadequate knowledge or heavy workload of ATC Controller leading to a clearance that would have placed us in-trail of this A380 Super as it descended through our altitude directly in front of us. Aircrew intervention placed us away from this Super aircraft instead of being right behind it initially. ATC directed us to speed up to close the gap in spacing behind the Super that put us in the zone to encounter its wake on the arrival. Wake turbulence encounter passing approximately 18000 ft descending on the RNAV Arrival due to proximity to the A380 Aircraft and its descent profile. This resulted in a strong to extreme wake turbulence event.Take away and suggestions to keep this from happening again:ATC and Aircrew Training to ensure we are aware of the significance of not only in-trail separation from Heavy or Super Category Aircraft; but also the factual and aerodynamic characteristics of wake vortices; and how they manifest themselves and move through the air. With an average descent rate of 500 ft per minute; wakes do not remain static. With increasing changes in configuration wakes become stronger. With tailwinds and crosswinds; the wake can linger longer in certain places which can affect an in-trail aircraft both on the initial arrival and descent as well as final approach. Strong emphasis how to vector other aircraft in behind Heavy or Super aircraft; especially when the Heavy or Super Aircraft is above and will be descending through the trailing aircraft's flight path. This is potentially very dangerous for the reasons that led up to this report. Though I was aware and asked questions and tried to mitigate the threat before it could create a hazard to my flight; other aircrew may not even have had a clue what was about to happen. Vertical and lateral in-trail separation needs to be greater following these Super aircraft especially with the constraints and crossing altitudes we experience on most RNAV arrivals. With at or above crossings; the potential exists that the preceding Super aircraft could be above the path of the following in-trail aircraft. Much like being a dot high on the glide path to final; the in-trail aircraft then faces the risk of encountering the wake of the preceding Heavy or Super during many phases of the RNAV descent profile. I believe that is what happened to us during our encounter. ATC; both Center and Approach Control; need to also ALWAYS inform following aircraft within a set range that they are crossing or following the path of a Heavy or Super aircraft. Currently that only seems to occur in the approach sector of flight into the Airports we serve. One other take away from this event. At each recurrent; we have the requirement and opportunity to do upset recoveries. Sometimes this is set up as though from a wake turbulence encounter following a Heavy aircraft. I am grateful for that training and; along with the awareness of the possibility of a wake encounter; I believe that this training helped to contribute to the successful recovery following this wake turbulence event.

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.