MD Helicopter MD 900, Weatherford, Texas, Oct. 8, 2008–The MD 900 experienced a violent yaw to the left while cruising near Weatherford with the autopilot on. The pilot regained control and continued to his destination, Grand Prairie Municipal Airport, without further incident. Investigators found that the vertical stabilizer control rod had separated from the actuator. No one was injured.
Hawker Beechcraft Beech 1900D, St. Louis, Mo., Sept. 7, 2008–The empennage of the Great Lakes Aviation 1900 struck a building overhang while parking at its gate at Lambert-St. Louis International Airport, aided by a marshaler and a wing walker. The vertical stabilizer was twisted and the rudder and the right side of the elevator were wrinkled. No one was injured.
A proposed AD that would require replacing the horizontal stabilizer trim actuator (HSTA) every 18 months on Citation 650s is based on a discovery in lab tests that the no-back friction brake within the HSTA “can degrade and allow the actuator to move without a command if an electrical failure is also present,” according to Cessna. At press time, the manufacturer said it had not received any reports of this condition in the field.
It has not been a good summer for the Cessna Citation 650 or 525. Last month, owners of the Cessna 650 Citation VII learned of a proposed AD (Docket No. 2002-NM-332-AD) that would require repetitive replacement of the horizontal stabilizer primary trim-actuator assembly with a repaired assembly.
Hawker Beechcraft Beech 99, Bowling Green, Mo., June 22, 2008–A parachutist jumping from the Skydive Factory Beech 99 hit the airplane’s horizontal stabilizer and was killed. The skydiver who jumped just before the accident realized the airplane was going too fast and maneuvered away from the aircraft’s tail section.
As an outgrowth of its continuing investigation into the November 12 crash of American Airlines Flight 587 in New York City, the NTSB has recommended that the FAA order manufacturers and operators of transport-category airplanes to revamp pilot-training programs with regard to rudder use.
A proposed airworthiness directive for the Sikorsky S-76 would require inspections of the tail rotor vertical stabilizer aft spar assembly every 50 hours after an assembly has 1,000 hours time-in-service. It would also require track and balance of the tail rotor within 30 days and every 200 hours thereafter. The AD would affect an estimated 216 S-76A/B/Cs on the U.S. registry.
Alenia Aeronautica has completed destructive testing on the horizontal stabilizer of the Boeing 787 Dreamliner, the companies announced today. The test took place at Alenia’s Pomigliano plant in Naples, Italy, in the presence of Boeing engineers and representatives of the FAA and European Aviation Safety Agency (EASA). Alenia manufactures the stabilizer at its plant in Foggia, Italy.
Boeing Business Jets are included in an emergency AD issued last month that prohibits using the speedbrakes on 737-600s and -700s at airspeeds in excess of 300 kias. The FAA said it issued the directive (AD 2002-08-52) after receiving a report that on April 5, a 737-700 with its speedbrakes deployed at 19,500 ft msl and 315 kias experienced “a severe high-frequency vibration” of the horizontal stabilizer.
In a situation reminiscent of the dilemma JetStar owners face, a substantial number of Cessna 441 Conquest II twin turboprops could be grounded come September unless modifications are made to the contents and administration of a Cessna program designed to deal with aging-aircraft issues.