The media stated that there was initial speculation that a bomb had destroyed the aircraft; however, the National Transportation Safety Board (NTSB) subsequently discovered that missing screws on the horizontal stabilizer led to the crash.[4]
Aircraft and crew
The aircraft involved in the accident, during its test flight, in 1989.
The Embraer 120 Brasilia, serial number 120077, was built in 1988, three years before the accident, and had accumulated 7,229 flight hours through 10,009 cycles.[1]: 8 The Federal Aviation Administration records stated that the aircraft had been sent to the maintenance hangar 33 times for unscheduled repairs.[5]
The crew consisted of 29-year-old captain Brad Patridge of Kingwood, Texas (Greater Houston), 43-year-old first officer Clint Rodosovich of Houston and 33-year-old flight attendant Nancy Reed of Humble, Texas.[6] Patridge and Rodosovich were experienced pilots with 4,243 flight hours and 11,543 flight hours (including 2,468 hours and 1,066 hours on the EMB 120 Brasilia), respectively.[1]: 5
Incident
The EMB 120 departed Laredo International Airport at 09:09, operating under Federal Aviation Regulation Part 135. After a normal takeoff, the flight was assigned a cruise altitude of flight level 250
(25,000 feet (7,600 m)), then reassigned to FL240 (24,000 feet (7,300 m)). At 09:54, the flight crew responded to the Houston Air Route Traffic Control Center and started descending to 9,000 feet (2,700 m). At approximately 10:03 while descending through 11,500 feet (3,500 m) with an indicated airspeed of 260 knots (300 mph; 480 km/h), the leading edge of the left horizontal stabilizer separated from the airframe, and the airplane pitched down dramatically, rolling around on an axis as the left wing folded.[1] The escaping fuel from the wings ignited, and the pilots lost consciousness from the severe g-forces, which reached at least 3.375 times the force of gravity,[1] caused by the severe oscillations of the crippled aircraft. The wreckage fell in southeast Colorado County, Texas, exploding on impact, off Farm to Market Road 102, seven miles (11 km) southeast of Eagle Lake, Texas,[7] and 60 miles (97 km) west of Downtown Houston.[8] The Texas Department of Public Safety announced that rescue units had discovered no survivors.[7] The wreckage was spread over a 2- to 4-square-mile (10 km2) area, and some pieces fell into the Colorado River.[8]Diamonds worth approximately $500,000 (1991 value; $1,100,000[9] in 2022) were discovered in the wreckage, but they had no role in the crash.[6]
Investigation
The National Transportation Safety Board (NTSB) investigation revealed that screws had been removed from the horizontal stabilizer during maintenance the night before the accident and, following a shift change, the screws had not been replaced.[1]: 48, 49 The aircraft's first flight of the day was uneventful because it did not reach the accident flight's top speed of 260 knots (480 km/h; 300 mph).[1]
The NTSB cited the failure of airline maintenance and inspection personnel to adhere to proper maintenance and quality-assurance procedures. The failure of Federal Aviation Administration (FAA) surveillance to detect and verify compliance with approved procedures was cited as a contributing factor.[1]: 49 Following the accident, the FAA conducted a National Aviation Safety Inspection Program (NASIP) of Continental Express'
maintenance program. It found very few safety deficiencies, and
complimented the airline on its internal evaluation system. The NTSB expressed concern that the NASIP did not find deficiencies in shift-turnover procedures and other matters relevant to the accident, and recommended that the agency improve its NASIP procedures.[citation needed]
Probable cause
The NTSB determined the probable causes of the accident as follows:
"The failure of Continental Express maintenance and inspection personnel to adhere to proper maintenance and quality assurance procedures for the airplane's horizontal stabilizer de-ice boots that led to the sudden in-flight loss of the partially secured left horizontal stabilizer leading edge and the immediate severe nose-down pitchover and breakup of the airplane. Contributing to the cause of the accident was the failure of the Continental Express management to ensure compliance with the approved maintenance procedures, and the failure of FAA surveillance to detect and verify compliance with approved procedures."[1]: 50
Role in developing the culture of safety
Some experts say that the crash of Continental Express Flight 2574 was the most dramatic turning point for "safety culture" in the United States.[10] NTSB member Dr. John Lauber suggested that the probable cause of the accident included "The failure of Continental Express management to establish a corporate culture which encouraged and enforced adherence to approved maintenance and quality assurance procedures."[1]: 54 As a result of this and other similar aviation accidents, safety culture became the main topic at the U.S. National Summit on Transportation Safety, hosted by the NTSB in 1997.[citation needed]
^Meshkati, N. (April 1997). Human Performance, Organizational Factors and Safety Culture. Symposium, Corporate culture and transportation safety; 1997; Arlington, VA. Washington: National Transportation Safety Board.
