N753CC

HISTORY OF FLIGHTOn December 21, 2012, about 1000 central standard time, a Cessna 550 Citation airplane, N753CC, impacted terrain while on approach to runway 17L at the Will Rogers World Airport (OKC), near Oklahoma City, Oklahoma. The pilot was uninjured and the copilot sustained minor injuries. The airplane sustained substantial wing and fuselage damage. The airplane was registered to and operated by the United States Customs Service under the provisions of 14 Code of Federal Regulations (CFR) Part 91 as a public use flight. Day visual flight rules (VFR) conditions prevailed for the flight. The local flight originated from OKC about 0920.

According to the operator's report, the purpose of the flight was a local VFR training flight. The crew consisted of two flight instructor pilots; one who was current and qualified in the airplane and the second pilot who was qualified but out of currency. This was to be a training flight for the pilot under instruction (PUI) to reset his currencies so he could attend re-current training. The PUI had recently returned from a 12-month military deployment and had not flown for more than a year.

The crew's preflight activities were described as routine. They attended the morning crew briefing, checked weather and notices to airmen, completed their pre-mission paperwork, and completed the preflight of the airplane together. The weather was forecast to be VFR conditions throughout the day.

The airplane departed OKC on runway 17L, VFR westbound and climbed to 12,500 feet above mean sea level (msl). The flight instructor was the pilot not flying (PNF) and sat in the left seat; the PUI was the pilot flying (PF) from the right seat. The PF completed a series of normal stalls and steep turns, then requested vectors back to OKC for a practice instrument landing system (ILS) approach on runway 17L followed by pattern work. The PF flew the practice ILS, and then made two touch-and-go landings. The PNF described PF's performance up to this point as being above average for someone who had not flown in a year and his approach and landings were described as excellent.

While on the right downwind leg, the crew advised the air traffic control (ATC) tower that they would make a full stop landing. ATC acknowledged, told them to extend their downwind leg, and stated that the controller would call their base turn. The controller then called out the landing traffic that was currently on final approach, which was an Airbus A300-600 heavy. The flight crew replied back that they had the traffic in sight, and the controller cleared the flight to land, number two behind the preceding Airbus, and advised to have caution for wake turbulence. The crew observed their position was abeam the Airbus and estimated that they made the base turn about three miles from the runway. While making the turn, the flight crew discussed wake turbulence avoidance procedures and planned to make a steeper approach and land beyond the Airbus's touchdown point. The PF added 10 to 15 knots to the Vref speed as a precaution. The reported winds provided by the tower controller were 180 degrees at 4 knots. The crew observed tire smoke from the Airbus as it touched down near the 1,500-foot runway markings. The flight crew discussed touching down at the 2,000-foot markings and continued. The Airbus continued on the runway, and the tower advised the Citation flight crew to be prepared for a go- around, should the Airbus not clear the runway in time, which the flight crew acknowledged. The flight crew estimated that the Airbus turned off the runway on taxiway F when they were about 1,000 feet from the threshold and about 200 feet above ground level (agl). The flight crew reported having a stabilized approach, and elected to continue while maintaining their planned landing point. When landing was assured, the PF reduced the power levers.

The operator indicated that when the airplane was approximately 150 feet agl, established on runway centerline, it had an uncommanded left roll to 60 degrees of bank or beyond. The heading swung to the left to about 130 degrees and the nose dropped. The flight crew reported that the airplane was buffeting heavily and that they momentarily lost sight of the horizon. Immediately, the PNF set full power and the PF used both hands on the control wheel in an attempt to roll the airplane level and recover the pitch. The PF managed to get the airplane nearly back to level when the right main landing gear struck the ground short of the threshold and left of the runway. Less than 50 feet after the right main landing gear had touched down, the airplane collided with a small drainage ditch and a dirt service road, causing the right main and the nose gear to collapse. The airplane skidded across a grassy area, across a taxiway, and before it came to rest it "ground looped" to the right in the infield between the taxiway and runway. A small ground fire had begun in the grassy area beyond the taxiway. The flight crew checked each other and immediately evacuated the airplane through the main cabin door. Upon exiting, they observed fuel pouring out of a hole in the left wing and elected to get a safe distance away from the airplane. The PNF had no injuries; the PF was taken to the hospital and treated for back pain.

The pilot flying an Air Force T-1 Jayhawk airplane, which was trailing the accident airplane, saw the accident sequence. He indicated that he had begun timing for wake turbulence as soon as the Airbus crossed the runway threshold and never visually acquired the Citation other than on the airplane's traffic collision avoidance system (TCAS). Based on TCAS, the Citation was about 3 miles in front of the T-1 and about 900 feet below the T-1's altitude. When the T-1 was about 4 miles from the threshold of the runway, the tower controller advised the Citation to expect a go-around. Shortly after this call, he visually acquired the Citation that was on short final as the wings rolled "nearly vertical," allowing the sun to be reflected in a "wing flash". He saw that the Citation subsequently impacted terrain short and slightly left of the runway striking right wing first. It then cart wheeled and stopped upright on a northwesterly heading. He also saw smoke, dust and debris, and flames/sparks upon impact. The T-1 was about three to four miles out on final at this point and was "coming up on (or shortly past)"the flight's two minute interval time for wake turbulence. The pilot estimated that the Citation was about a minute or less behind the Airbus and was on a low final based on the T-1's TCAS indications. The Airbus was just turning off the runway as the Citation was approaching about a 1/2 to 1/4 mile final at 100 to 200 feet when it encountered the wake. The T-1 pilot stated that, after the crash, the T-1's crew began a go-around and were subsequently given ATC instructions to go-around. On the go-around, the pilot noticed the Citation's airframe was still intact and he did not notice any post-impact fire.

Video cameras at the airport recorded the accident sequence. A video showed the accident airplane following approximately 51 seconds behind an Airbus airplane landing on the same runway. The video showed the accident airplane rolled left to about a bank angle of 60 degrees and a heading of approximately 140 degrees before recovering to a right-wing-low, nose-down attitude and impacting terrain. The right wing fuel tank ruptured, the airplane skidded along grass, crossed an airport perimeter road, crossed taxiway hotel, and came to rest upright near a parking lot along the east side of runway 17. PERSONNEL INFORMATIONPilot Not Flying

The 49-year old pilot, who was seated in the left seat, held a Federal Aviation Administration (FAA) airline transport pilot certificate with a multiengine land rating with commercial pilot privileges for single engine land airplanes. He held a Cessna 500 type rating and a certified flight instructor rating with single-engine, multiengine, and instrument airplane ratings. According to the operator's report, the pilot had accumulated 5,097 hours of total flight time and 420 hours of flight time in the same make and model as the accident airplane. The pilot held a second-class medical certificate with a limitation for corrective lenses.

Pilot Flying

The 41-year old co-pilot, who was seated in the right seat, held a FAA airline transport pilot certificate with a multiengine land rating with commercial pilot privileges for single engine land airplanes and rotorcraft and instrument helicopters. He held Cessna 500 and Beechcraft 200 type ratings and a certified flight instructor rating with single-engine, multiengine, and instrument airplane ratings. According to the operator's report, the pilot had accumulated 357 hours of flight time in the same make and model as the accident airplane. The pilot held a second-class medical certificate without limitations. AIRCRAFT INFORMATIONN753CC, a Cessna model 550 (Citation), with serial number 550-0109, was a twin-engine, turbojet airplane. The airplane was configured to seat four occupants. The transport category airplane was powered with two Pratt & Whitney Canada JT-15D-4 turbofan engines, serial numbers PCE-71690 and PCE-70313, each capable of producing 2,500 pounds of thrust. The operator reported that the airplane was maintained under an annual inspection program and its most recent continuous airworthiness inspection was completed on April 23, 2012, when the airplane accumulated 13,506 hours of total time. METEOROLOGICAL INFORMATIONA National Transportation Safety Board (NTSB) senior meteorologist produced a meteorology group chairman's report for the investigation. His report indicated that a surface analysis chart for 0900 on December 21, 2012, depicted a col or neutral zone centered over Oklahoma with a weak pressure gradient over the area, with resulting light winds. No boundaries were identified over the area to result in an...