Date: 201212
Local time of day: 0601-1200
Location: OKC.Airport, OK
Flight conditions: VMC
Weather elements / visibility: 20
Light: Daylight
Aircraft: Citation II S2/Bravo (C550)
Operator: Government
Operating under: Part 91
Flight plan: None
Mission: Training
Flight phase: Final Approach
Airspace: Class C OKC
ATC / advisory: Tower OKC
Second aircraft: A330
Reporter organization: Government
Reporter function: Captain; Instructor; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor
Human factors: Situational Awareness
Anomaly: Inflight Event / Encounter Wake Vortex Encounter; Inflight Event / Encounter Loss Of Aircraft Control
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Executed Go Around / Missed Approach; Flight Crew Regained Aircraft Control
Contributing factors: Human Factors; Environment - Non Weather Related
Primary problem: Environment - Non Weather Related

Narrative: We turned final for a planned full stop landing approximately 2 miles behind an Airbus A330. Tower advised 'caution wake turbulence'. We discussed and executed making steeper approach and landing long to avoid wake turbulence. The pilot flying intentionally added 10-15 KTS above normal approach speed as a precaution. The [Airbus] jet landed approximately 1;500 FT down the runway and we noted his 'smoke vortices' from the tires touching down; and planned to land beyond them. Tower advised us to 'be prepared to go around' and we agreed we would be ready. The [Airbus] turned off at Taxiway F while we were approximately 1;000 FT from the threshold at approximately 200 FT AGL. We elected to continue the landing as planned with the aim-point beyond the Airbus touchdown. While established on the extended Runway 17L centerline; heading 175; at approximately 150 FT AGL; our aircraft violently rolled into approximately 60 degree left bank; veered to an approximately 130 degree heading; started heavy buffet and sinking. Simultaneously; the pilot not flying pushed both throttles full forward and the pilot flying manipulated the flight controls as we attempted to execute a go-around. After rolling back to a wings level attitude but still buffeting and with a sink rate; the aircraft touched down on the grass heading 130. We touched down less than 3 seconds after initiating the go-around. A nearby security camera showed that we were 51 seconds behind the Airbus and that the wake turbulence upset occurred at approximately 100 FT AGL and on the same glide path as the Airbus. I can not explain why the glide path/touchdown aim-point picture we were seeing from our cockpit did not match reality as seen by the camera. I can only conclude that visually judging your glide path and touchdown point vs. that of an aircraft 2 miles in front of you is not as straight-forward/obvious as I believed it to be. I had been a USAF T-6 pilot training IP and the other pilot had been a USN T-34 pilot training IP. Both included extensive instructing of aerobatics and a wide assortment of unusual attitudes. Also; we had both attended an Upset Recovery Training course. I am firmly convinced that our backgrounds are the only reason we walked away from this event. Educate pilots that just visually de-conflicting your glide path/touchdown point from a preceding aircraft may not be giving you the safety margin you think it is; especially when close to the flare. Establish a minimum distance interval for landing behind 'heavy' aircraft; especially when the winds are less than 10 knots. ATP candidates should be required to have an 'Upset Recovery Training' endorsement similar to CFI candidates needing a 'Spin Training' endorsement. Encourage pilots to execute a go-around anytime they even consider it and not wait until they actually see the need for it.




Synopsis: A C550 crew hit the grass during a go around after encountering wake vortices during landing in OKC.