The pilots of a 1995 Cessna Citation VII (N877G) that experienced severe roll control problems on departure from Fort Lauderdale Executive airport on the morning of 28 December used a combination of alternative control techniques to bring the twin-engine business jet, with eight people on board, back to the airport.
According to the US National Transportation Safety Board's preliminary report, issued on 5 January, the first officer described the pilot as having "extreme" difficulty in rolling the aircraft level after departing Runway 26 for the 2h30min Part 91 instrument flight rules trip to Teterboro with six passengers on board.
"After taking off and obtaining a positive rate of climb, the captain found that he needed a 'little left [roll] control', then the airplane started a slow right turn which he could not stop," the report stated. The co-pilot and one passenger said roll angles approached 90 degrees of bank during the incident.
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The captain quickly determined that a combination of left aileron, left rudder and varying levels of differential thrust as a function of speed could be used to keep the aircraft from rolling over. As the business jet's path continued an arc to the right, the captain "saw that the airplane was gradually lining up with Runway 13" and he decided that he had a "one-time shot" at landing on the airport, according to the NTSB. The captain initially thought there may have been a flap asymmetry causing the problem, but no warning lights displayed.
The aircraft landed long on the runway but swerved off it and hit a perimeter fence, damaging the wing leading edge, skin and nose wheel. There were no injuries to pilots or passengers.
NTSB investigators later found the aircraft's outermost hydraulically actuated spoiler on the right side would not fully retract unless a spoiler "hold-down switch" was activated, a deflection that would cause a roll to the right in flight. The roll spoilers, one on either side of the aircraft, are used to augment the ailerons for roll control.
The right roll spoiler control components - a bell crank and hydraulic actuator - are being analysed as the investigation continues.
Source: Flight International
