IAI1125 (Astra)
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Last 90 Days 55; Flight Crew Total 15000; Flight Crew Type 500
ATC Issue All Types; Deviation - Altitude Excursion From Assigned Altitude; Inflight Event / Encounter Wake Vortex Encounter
Flight Crew Returned To Clearance
Procedure; Environment - Non Weather Related
While in cruise at FL390; Center advised 'Caution; wake turbulence from an Airbus 380 Super crossing from left to right; at FL400'. After establishing visual contact with the traffic; I requested a temporary lower altitude until passing behind the traffic. We were advised that was not available due to additional traffic at FL380. Within a minute; we encountered wake turbulence from the A380. Our plane rolled left; pitched down and the autopilot disconnected. After manually stabilizing the aircraft; the altimeter was observed to be 250 FT below assigned altitude. After climbing back to FL390 and re-engaging the autopilot; Center asked us to verify our altitude. We did so; which was then level at FL390. I believe an earlier traffic-alert from Memphis Center would have provided us with sufficient time to have asked for a turn off-course; thereby enabling us to avoid the wake turbulence.
[Report narrative contained no additional information.]
IA-1125 flight crew reported a wake vortex encounter at FL390 with an A380 that passed in front of them. The resulting turbulence caused a 250 FT loss of altitude.