Incident - Dec. 17, 2007 - Jamaica, N.Y.
The flight, operated by Chautauqua Airlines Inc., was scheduled to depart from New York, N.Y. en route to Buffalo,N.Y..
HISTORY OF FLIGHT
On December 17, 2007, at 3:30 pm, Eastern Standard Time, the flight crew of a Chautauqua Airlines Embraer EMB-145 performed an emergency high-speed aborted takeoff at John F. Kennedy International Airport (JFK) due to a serious elevator malfunction. The malfunction completely disabled the elevator system of the aircraft, either before or while the captain was rotating the aircraft for flight. The captain stated that during the rotation maneuver he felt an anomaly that caused him to abort the takeoff and stop the aircraft. Taxi back to the gate was uneventful and all 50 passengers and three flight crewmembers deplaned normally.
INJURIES TO PERSONS
No injuries were reported
DAMAGE TO AIRPLANE
Following the incident, an internal inspection of the elevator control system components revealed that both left and right elevator control rod assemblies (P/N 145-22141-405) had fractured completely through their circumferences rendering the elevator control of the aircraft inoperable. In addition, damage to control stops and horizontal stabilizer sheet metal was observed. A metallurgical examination of the control rods indicated that both failed in compression with some bending moment observed.
A gust lock system is installed on the aircraft to lock the elevator to avoid damage to elevator components when the aircraft is subjected to strong gusts on the ground.
The EMB 145 can be equipped with either a mechanical gust lock system or an electromechanical gust lock system. The incident aircraft was equipped with a mechanical gust lock system. The mechanical gust lock is designed to immobilize the forward torque tube, which is attached to the control column, when it is engaged. Some stretching of elevator cables will occur when the elevator surface is exposed to high loads.
The electromechanical gust lock system uses a locking mechanism that acts directly on the elevator. The gust lock lever in the cockpit activates an electromechanical actuator that drives locking pins into the elevator panels. No stretching of the elevator cables can occur with the electromechanical gust lock system engaged.
In response to this incident, Embraer issued a service bulletin and subsequently revised it twice:
Embraer Alert Service Bulletin 145-27-A106R00 was issued on December 23, 2007. This service bulletin advised operators to perform a detailed inspection of the elevator control system (including a check to insure that the elevators responded properly to control column inputs) within the next 20 flight hours, and it also advised the operators to repeat these inspections any time the aircraft was exposed to wind gusts over 35 knots while on the ground. This service bulletin only applied to aircraft that did not already have the electromechanical gust lock system installed.
This service bulletin was revised on December 27, 2007. The revised service bulletin advised operators to perform the detailed inspection of the elevator control system, perform a daily check prior to the first flight of the day to insure proper elevator response to control column movements, and to repeat the detailed elevator control system check every 600 flight hours or if the aircraft is exposed to wind gusts over 50 knots while on the ground. These actions would be no longer required when an electromechanical gust lock system was installed on the aircraft.
The service bulletin was revised again on December 28, 2007. This revision modified the daily elevator inspection to include a provision for performing a detailed check of the elevator skin around the hinge areas while the elevators were held in a trailing edge up position. A copy of this service bulletin is included as appendix A.
The Federal Aviation Administration (FAA) incorporated the service bulletin’s recommended actions (with some minor revisions) in Airworthiness Directive AD-2008-03-03, effective February 14, 2008.
Earlier, on November 8, 2002, the Brazilian National Civil Aviation Agency issued airworthiness directive 2002-01-01R3, requiring the eventual replacement of mechanical gust lock systems with electromechanical systems in EMB 145 aircraft flown in Brazil. On February 3, 2006, the FAA issued airworthiness directive 2005-26-15, that required US operators of EMB 145 aircraft to installelectromechanical gust lock systems within 10,000 flight hours or 60 months.
According to the manufacturer, all EMB 145 aircraft now have electromechanical gust lock systems.
Prior to the accident flight, the aircraft was parked overnight at JFK airport with its tail pointed into the wind. During the night the winds were reported to range between 30 and 40 knots.