Incident Description
On December 1, 2010, about 1336 eastern standard time, a Cessna 560XL, registration N607QS, operated by NetJets Aviation, Inc., experienced a loss of rudder authority during landing at the Toledo Express Airport (TOL), near Toledo, Ohio. The rudder bound as the pilot flying attempted a crosswind correction during the flare. The airplane landed without incident and was undamaged. The two pilots and one passenger were not injured. Visual meteorological conditions prevailed, and the flight operated under an instrument flight rules flight plan as a non-scheduled domestic passenger flight under 14 Code of Federal Regulations Part 135. The flight departed Monmouth Executive Airport (BLM), near Belmar, New Jersey, about 1159.
Preflight and Flight
On November 29, 2010, the airplane landed at Philadelphia International Airport (PHL) and was parked on the ramp for 30 hours, during which light rain was reported. On November 30, the flightcrew repositioned the airplane from PHL to BLM, parking it under an open canopy. On the morning of December 1, during a preflight inspection at BLM, moderate rain was falling with a temperature of 15°C. The inspection of control cables in the aft equipment bay revealed no discrepancies. Engine start, taxi, flight control checks, and rudder bias check were normal.
The flight departed through light to moderate rain until west of PHL airspace, then climbed to flight level 400. The cruise portion was above the freezing level. The airplane broke out of clouds during climb about 14,000 feet MSL and remained in clear conditions until descent through 8,000 feet MSL on approach to TOL. During approach, the autopilot was disconnected at 2,500 feet MSL, and the yaw damper was disconnected at 600 feet AGL. The temperature at TOL recorded at 1252 was -2°C. No problems were noted until the landing flare, when the flying pilot found the rudder pedals immovable. After landing, with engines shut down, the rudder pedals remained stuck, and the rudder could not be moved manually.
Postflight Examination
Postflight examination by maintenance personnel revealed ice accumulated in the tailcone stinger, which interfered with rudder control cables and pulleys, rendering the rudder immovable. The airplane, serial number 560-5340, had a tailcone stinger part number 6612119-60 with a 0.182-inch drain hole, smaller than the 0.201-inch hole specified in Cessna service letter SL560XL-53-05 issued on April 1, 2005. This service letter applied to serial numbers 560-5002 through 560-5544; airplanes with higher serial numbers had factory-installed drain holes. The incident airplane fell within the range but had an undersized hole. An FAA inspector also examined three other Cessna 560XLs in the same hangar: serial numbers 560-5305, 560-5548, and 560-5661, all with drain holes smaller than specified. Serial numbers 560-5548 and 560-5661 should have had correct factory-installed holes.
Related Incidents
According to preliminary information provided to the NTSB, on December 13, 2010, a Cessna 560XL, N498AB, sustained no damage when its rudder bound during landing at Birmingham-Shuttlesworth International Airport (BHM) in Birmingham, Alabama. On December 20, 2010, another Cessna 560XL, N626QS, also experienced rudder binding during landing at Idaho Falls Regional Airport (IDA) without damage. On March 10, 2011, a Cessna 560XL operated by NetJets, N588QS, experienced stuck rudder controls while climbing through approximately 28,000 feet near Haynesville, Maryland; this airplane had been modified to comply with alert service letter ASL560XL-53-08.
Service Actions
In response to the incidents, Cessna issued alert service letter ASL560XL-53-08 on January 21, 2011, stating the stinger may not drain water, allowing ice to form around rudder bias cable pulleys. The letter provided instructions for inspecting and drilling drain holes in frames and sealing an existing drain hole while adding a new one. Compliance was mandatory within 90 flight hours or 90 days. On March 15, 2011, the NTSB issued Safety Recommendation A-11-16 to the FAA, recommending an airworthiness directive requiring compliance with ASL560XL-53-08. Cessna subsequently issued service bulletin SB560XL-53-16 on October 4, 2011, titled Fuselage – Stringer Drain Installation, which provided parts and instructions for installing a drain and seal to improve water drainage from the stinger. The FAA’s Wichita Aircraft Certification Office approved both service actions. An FAA audit in May 2011 did not detect misdrilled drain holes on production airplanes, but Cessna later instituted specific inspection characteristics to verify drain hole installation. A follow-up inspection on August 16, 2011, verified engineering requirements.