Atlantic Southeast Airlines Flight 2311
Encyclopedia
Atlantic Southeast Airlines
Flight 2311 was a regularly scheduled commuter flight from Atlanta, Georgia
to Brunswick, Georgia
which suffered an uncontrolled collision with terrain during landing approach to Glynco Jetport (later renamed Brunswick Golden Isles Airport), just north of Brunswick, on April 5, 1991. The aircraft was an Embraer 120RT Brasilia, registered N270AS. None of the 20 passengers and 3 crew on board survived the accident.
A few minutes before the aircraft impacted with the ground, controllers at Glynco Jetport cleared flight 2311 for a visual approach to runway 07 at the airport. Witnesses reported that as the airplane approached the airport, it suddenly turned or rolled to the left until the wings were perpendicular to the ground. The airplane then fell in a nose-down attitude and disappeared out of sight behind the trees. Just four years passed after that accident, when another Embraer Brasilia of ASA crashed in Georgia Countryside, with 9 fatalities aboard.
two Pratt & Whitney
PW-118 engines and Hamilton Standard
14RF-9 propeller
s. The airplane received its U.S. standard airworthiness certificate on December 20, 1990. The aircraft had accumulated about 816 flying hours prior to the accident. Only one deferred maintenance item was noted in the maintenance logs. This was for fuel leaking from the auxiliary power unit
cowling. The circuit breaker for the APU had been pulled whilst spare parts could be made available to fix the cowling.
The captain, age 34, had been hired by Atlantic Southeast on in May 1981. He was fully qualified to fly three different commercial aircraft including the EMB-120. It was estimated that at the time of the accident he had accumulated about 11,724 total flying hours, of which 5,720 hours were in the EMB-120. He had been involved in the development of the EMB-120 and its introduction to service in the United States, and was trained to fly the aircraft by the manufacturer. An inspector described his knowledge of aircraft systems "extensive", and his pilot techniques as "excellent".
The first officer, age 36, was hired by Atlantic Southeast in June 1988. He was a qualified flight instructor
. Because more than 6 months had passed since he had undergone an FAA medical inspection and he was issued with a first-class certificate, it automatically reverted to a second class certificate. A second class certification was adequate for his duties as a first officer. At the time of the accident, it was estimated that he had accumulated about 3,925 total flying hours, of which 2,795 hours were in the EMB-120.
and the first officer arrived at the airport by taxi about 06:15. The taxi cab driver reported that the crew was in good spirits and readily engaged in conversation. The crew flew first to Atlanta, then performed a round trip to Montgomery
, Alabama
, before returning to Atlanta. After this round trip, the crew had a scheduled break for around two and a half hours, in which they were described to be well rested and talkative.
Flight 2311 was scheduled initially to be operated by N228AS, another EMB-120
. However, this airplane experienced mechanical problems, and so the flight was switched to N270AS. This aircraft had flown four times already on the day of the accident with no reports of any problems. The flight departed just before 14:00.
The flight crew then took off 23 minutes behind their planned schedule and flew the aircraft to Brunswick, deviating slightly to avoid poor weather
. Just after 14:48, the flight crew acknowledged to Jacksonville air route traffic control center that the airport was in sight, and flight 2311 was subsequently cleared for a visual approach
to Glynco Jetport, which the flight crew acknowledged.
The last transmission received from flight 2311 was to the ASA manager at the airport, who reported that the flight made an “in-range call” on the company radio frequency and that the pilot gave no indication that the flight had any mechanical problems. Witnesses reported seeing the aircraft approaching the airport in visual meteorological conditions
at a much lower than normal altitude
. Several witnesses estimated that the aeroplane flew over them at an altitude of 100 to 200 feet above the ground.
The majority of the witnesses reported that the aircraft suddenly rolled to the left until the wings were perpendicular
to the ground. The aircraft then descended in a nose-down attitude and disappeared from sight behind trees near the airport. One witness told investigators that they saw a puff of smoke emanate from the aircraft prior to or subsequent to the airplane rolling to the left. Others reported loud engine noises described as a squeal, whine, or an overspeeding or accelerating engine during the last moments of the flight, although they said that these noises seemed to have stopped, or at least faded before the aircraft impacted with flat ground two miles short of the runway.
An observer driving along a road southwest of the airport told an NTSB investigation that he saw the airplane in normal flight at normal altitudes, and that he believed that the approach was not abnormal. The airplane completed a 180-degree turn from the downwind leg of the approach and continued the turn. He then saw the aircraft pitch slightly, before it rolled to the left until the wings were vertical. The airplane then turned nose-down and smashed into the ground. He saw no fire
or smoke
during the flight and he believed both propellers were rotating.
initially determined that a malfunction of the asymmetric flaps, ailerons or rudder could not have caused the accident, after multiple pilots in simulators managed to keep the aircraft under control. Engine failure was also ruled out by detailed inspection of the two engines. The investigators found that
The NTSB found that the flight crew would have been unable to perceive any problem with the airplane until the propeller blade angle was between 24 and 26 degrees. They stated that the airplane would have "become very difficult to control after the propeller reached the 22-degree stop. Therefore, it is most likely that the pilots of flight 2311 did not notice a problem with the airplane until the propeller began to overspeed and roll control was affected." Thus, the flight crew would have been unable to declare an emergency as the event was so sudden.
Whilst in the final report, it was accepted that the fact that Atlantic Southeast was overworking pilots, estimating that the pilots only received 5 to 6 hours of sleep, contrary to FARs
played no part in the accident, the NTSB raised concerns that the airline, along with other commuter airline corporations, "scheduled reduced rest periods for about 60 percent of the layovers in its day-to-day operations. The Safety Board believes that this practice is inconsistent with the level of safety intended by the regulations, which is to allow reduced rest periods as a contingency to a schedule disruption, and has the potential of adversely affecting pilot fitness and performance."
Eventually, the NTSB concluded that the probable cause of the accident was:
senator John Tower
, 65, his daughter Marian, astronaut
Manley "Sonny" Carter
, and American College of Physicians
president-elect Dr. Nicholas Davies were among the 23 passengers and crew killed.. Two children, Brian and Laura Birdsong, ages 9 and 6, also died in the accident. A statue was erected in their memory at Atlanta Zoo.
Atlantic Southeast Airlines
Atlantic Southeast Airlines is an American airline based in the A-Tech Center in College Park, Georgia, flying to 144 destinations as a Delta Connection carrier and, as of February 2010, commenced service as a United Express carrier. It is a wholly owned subsidiary of SkyWest, Inc. ASA operates...
Flight 2311 was a regularly scheduled commuter flight from Atlanta, Georgia
Atlanta, Georgia
Atlanta is the capital and most populous city in the U.S. state of Georgia. According to the 2010 census, Atlanta's population is 420,003. Atlanta is the cultural and economic center of the Atlanta metropolitan area, which is home to 5,268,860 people and is the ninth largest metropolitan area in...
to Brunswick, Georgia
Brunswick, Georgia
Brunswick is the major urban and economic center in southeastern Georgia in the United States. The municipality is located on a harbor near the Atlantic Ocean, approximately 30 miles north of Florida and 70 miles south of South Carolina. Brunswick is bordered on the east by the Atlantic...
which suffered an uncontrolled collision with terrain during landing approach to Glynco Jetport (later renamed Brunswick Golden Isles Airport), just north of Brunswick, on April 5, 1991. The aircraft was an Embraer 120RT Brasilia, registered N270AS. None of the 20 passengers and 3 crew on board survived the accident.
A few minutes before the aircraft impacted with the ground, controllers at Glynco Jetport cleared flight 2311 for a visual approach to runway 07 at the airport. Witnesses reported that as the airplane approached the airport, it suddenly turned or rolled to the left until the wings were perpendicular to the ground. The airplane then fell in a nose-down attitude and disappeared out of sight behind the trees. Just four years passed after that accident, when another Embraer Brasilia of ASA crashed in Georgia Countryside, with 9 fatalities aboard.
Atlantic Southeast Airlines Flight 529
Atlantic Southeast Airlines Flight 529, registration N256AS, was an Embraer Brasilia aircraft that crashed near Carrollton, Georgia on August 21, 1995 while on a flight from the Hartsfield-Jackson Atlanta International Airport to Gulfport-Biloxi International Airport in Gulfport, Mississippi...
Flight history
The aircraft involved in the accident was an Embraer EMB-120 Brasilia, manufactured on November 30, 1990. It was equipped withtwo Pratt & Whitney
Pratt & Whitney
Pratt & Whitney is a U.S.-based aerospace manufacturer with global service operations. It is a subsidiary of United Technologies Corporation . Pratt & Whitney's aircraft engines are widely used in both civil aviation and military aviation. Its headquarters are in East Hartford, Connecticut, USA...
PW-118 engines and Hamilton Standard
Hamilton Standard
Hamilton Standard, an aircraft propeller parts supplier, was formed in 1929 when United Aircraft and Transport Corporation consolidated Hamilton Aero Manufacturing and Standard Steel Propeller into the Hamilton Standard Propeller Corporation. Other members of the corporation included Boeing,...
14RF-9 propeller
Propeller (aircraft)
Aircraft propellers or airscrews convert rotary motion from piston engines or turboprops to provide propulsive force. They may be fixed or variable pitch. Early aircraft propellers were carved by hand from solid or laminated wood with later propellers being constructed from metal...
s. The airplane received its U.S. standard airworthiness certificate on December 20, 1990. The aircraft had accumulated about 816 flying hours prior to the accident. Only one deferred maintenance item was noted in the maintenance logs. This was for fuel leaking from the auxiliary power unit
Auxiliary power unit
An auxiliary power unit is a device on a vehicle that provides energy for functions other than propulsion. They are commonly found on large aircraft, as well as some large land vehicles.-Function:...
cowling. The circuit breaker for the APU had been pulled whilst spare parts could be made available to fix the cowling.
The captain, age 34, had been hired by Atlantic Southeast on in May 1981. He was fully qualified to fly three different commercial aircraft including the EMB-120. It was estimated that at the time of the accident he had accumulated about 11,724 total flying hours, of which 5,720 hours were in the EMB-120. He had been involved in the development of the EMB-120 and its introduction to service in the United States, and was trained to fly the aircraft by the manufacturer. An inspector described his knowledge of aircraft systems "extensive", and his pilot techniques as "excellent".
The first officer, age 36, was hired by Atlantic Southeast in June 1988. He was a qualified flight instructor
Flight instructor
A flight instructor is a person who teaches others to fly aircraft. Specific privileges granted to holders of a flight instructor qualification vary from country to country, but very generally, a flight instructor serves to enhance or evaluate the knowledge and skill level of an aviator in pursuit...
. Because more than 6 months had passed since he had undergone an FAA medical inspection and he was issued with a first-class certificate, it automatically reverted to a second class certificate. A second class certification was adequate for his duties as a first officer. At the time of the accident, it was estimated that he had accumulated about 3,925 total flying hours, of which 2,795 hours were in the EMB-120.
Accident
On the morning of the accident, the captainPilot in command
The pilot in command of an aircraft is the person aboard the aircraft who is ultimately responsible for its operation and safety during flight. This would be the "captain" in a typical two- or three-pilot flight crew, or "pilot" if there is only one certified and qualified pilot at the controls of...
and the first officer arrived at the airport by taxi about 06:15. The taxi cab driver reported that the crew was in good spirits and readily engaged in conversation. The crew flew first to Atlanta, then performed a round trip to Montgomery
Montgomery, Alabama
Montgomery is the capital of the U.S. state of Alabama, and is the county seat of Montgomery County. It is located on the Alabama River southeast of the center of the state, in the Gulf Coastal Plain. As of the 2010 census, Montgomery had a population of 205,764 making it the second-largest city...
, Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
, before returning to Atlanta. After this round trip, the crew had a scheduled break for around two and a half hours, in which they were described to be well rested and talkative.
Flight 2311 was scheduled initially to be operated by N228AS, another EMB-120
Embraer EMB 120 Brasilia
-Accidents:*Brazilian Air Force on July 8, 1988 an Embraer EMB 120RT Brasília registration FAB-2001 crashed during and engine-out landing at São José dos Campos. Five of the 9 occupants died....
. However, this airplane experienced mechanical problems, and so the flight was switched to N270AS. This aircraft had flown four times already on the day of the accident with no reports of any problems. The flight departed just before 14:00.
The flight crew then took off 23 minutes behind their planned schedule and flew the aircraft to Brunswick, deviating slightly to avoid poor weather
Weather
Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy. Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate...
. Just after 14:48, the flight crew acknowledged to Jacksonville air route traffic control center that the airport was in sight, and flight 2311 was subsequently cleared for a visual approach
Visual approach
The Federal Aviation Administration , defines a visual approach as one conducted under instrument flight rules , which authorizes the pilot to proceed visually and clear of clouds to the airport. The pilot must, at all times, have either the airport or the preceding aircraft in sight...
to Glynco Jetport, which the flight crew acknowledged.
The last transmission received from flight 2311 was to the ASA manager at the airport, who reported that the flight made an “in-range call” on the company radio frequency and that the pilot gave no indication that the flight had any mechanical problems. Witnesses reported seeing the aircraft approaching the airport in visual meteorological conditions
Visual meteorological conditions
In aviation, visual meteorological conditions is an aviation flight category in which visual flight rules flight is permitted—that is, conditions in which pilots have sufficient visibility to fly the aircraft maintaining visual separation from terrain and other aircraft. They are the opposite of...
at a much lower than normal altitude
Altitude
Altitude or height is defined based on the context in which it is used . As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context...
. Several witnesses estimated that the aeroplane flew over them at an altitude of 100 to 200 feet above the ground.
The majority of the witnesses reported that the aircraft suddenly rolled to the left until the wings were perpendicular
Perpendicular
In geometry, two lines or planes are considered perpendicular to each other if they form congruent adjacent angles . The term may be used as a noun or adjective...
to the ground. The aircraft then descended in a nose-down attitude and disappeared from sight behind trees near the airport. One witness told investigators that they saw a puff of smoke emanate from the aircraft prior to or subsequent to the airplane rolling to the left. Others reported loud engine noises described as a squeal, whine, or an overspeeding or accelerating engine during the last moments of the flight, although they said that these noises seemed to have stopped, or at least faded before the aircraft impacted with flat ground two miles short of the runway.
An observer driving along a road southwest of the airport told an NTSB investigation that he saw the airplane in normal flight at normal altitudes, and that he believed that the approach was not abnormal. The airplane completed a 180-degree turn from the downwind leg of the approach and continued the turn. He then saw the aircraft pitch slightly, before it rolled to the left until the wings were vertical. The airplane then turned nose-down and smashed into the ground. He saw no fire
Fire
Fire is the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products. Slower oxidative processes like rusting or digestion are not included by this definition....
or smoke
Smoke
Smoke is a collection of airborne solid and liquid particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product of fires , but may also be used for pest...
during the flight and he believed both propellers were rotating.
Investigation
An investigation carried out by the National Transportation Safety BoardNational Transportation Safety Board
The National Transportation Safety Board is an independent U.S. government investigative agency responsible for civil transportation accident investigation. In this role, the NTSB investigates and reports on aviation accidents and incidents, certain types of highway crashes, ship and marine...
initially determined that a malfunction of the asymmetric flaps, ailerons or rudder could not have caused the accident, after multiple pilots in simulators managed to keep the aircraft under control. Engine failure was also ruled out by detailed inspection of the two engines. The investigators found that
the circumstances of this accident indicate that a severe asymmetric thrust condition caused a left roll that led to loss of control of the airplane. The investigation examined all the possible events that could have caused the loss of control. The powerplant and propeller examinations indicated that the engines were operating normally but that a propeller system malfunction
occurred which caused abnormally low propeller blade angles and a high drag condition on the left side of the aeroplane.
The NTSB found that the flight crew would have been unable to perceive any problem with the airplane until the propeller blade angle was between 24 and 26 degrees. They stated that the airplane would have "become very difficult to control after the propeller reached the 22-degree stop. Therefore, it is most likely that the pilots of flight 2311 did not notice a problem with the airplane until the propeller began to overspeed and roll control was affected." Thus, the flight crew would have been unable to declare an emergency as the event was so sudden.
Whilst in the final report, it was accepted that the fact that Atlantic Southeast was overworking pilots, estimating that the pilots only received 5 to 6 hours of sleep, contrary to FARs
Federal Aviation Regulations
The Federal Aviation Regulations, or FARs, are rules prescribed by the Federal Aviation Administration governing all aviation activities in the United States. The FARs are part of Title 14 of the Code of Federal Regulations...
played no part in the accident, the NTSB raised concerns that the airline, along with other commuter airline corporations, "scheduled reduced rest periods for about 60 percent of the layovers in its day-to-day operations. The Safety Board believes that this practice is inconsistent with the level of safety intended by the regulations, which is to allow reduced rest periods as a contingency to a schedule disruption, and has the potential of adversely affecting pilot fitness and performance."
Eventually, the NTSB concluded that the probable cause of the accident was:
the loss of control in flight as a result of a malfunction of the left engine propeller control unit which allowed the propeller blade angles to go below the flight idle position. Contributing to the accident was the deficient design of the propeller control unit by Hamilton StandardHamilton StandardHamilton Standard, an aircraft propeller parts supplier, was formed in 1929 when United Aircraft and Transport Corporation consolidated Hamilton Aero Manufacturing and Standard Steel Propeller into the Hamilton Standard Propeller Corporation. Other members of the corporation included Boeing,...
and the approval of the design by the Federal Aviation AdministrationFederal Aviation AdministrationThe Federal Aviation Administration is the national aviation authority of the United States. An agency of the United States Department of Transportation, it has authority to regulate and oversee all aspects of civil aviation in the U.S...
. The design did not correctly evaluate the failure mode that occurred during this flight, which resulted in an uncommanded and uncorrectable movement of the blades of the airplane’s left propeller below the flight idle position.
Notable passengers
TexasTexas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
senator John Tower
John Tower
John Goodwin Tower was the first Republican United States senator from Texas since Reconstruction. He served from 1961 until his retirement in January 1985, after which time he was the chairman of the Reagan-appointed Tower Commission that investigated the Iran-Contra Affair. He was George H. W...
, 65, his daughter Marian, astronaut
Astronaut
An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....
Manley "Sonny" Carter
Sonny Carter
Manley Lanier "Sonny" Carter, Jr. was an American physician, professional soccer player, naval officer, and NASA astronaut who flew on STS-33.-Early life:...
, and American College of Physicians
American College of Physicians
The American College of Physicians is a national organization of doctors of internal medicine —physicians who specialize in the prevention, detection, and treatment of illnesses in adults. With 130,000 members, ACP is the largest medical-specialty organization and second-largest physician group in...
president-elect Dr. Nicholas Davies were among the 23 passengers and crew killed.. Two children, Brian and Laura Birdsong, ages 9 and 6, also died in the accident. A statue was erected in their memory at Atlanta Zoo.
See also
- List of notable accidents and incidents on commercial airliners
- Atlantic Southeast Airlines Flight 529Atlantic Southeast Airlines Flight 529Atlantic Southeast Airlines Flight 529, registration N256AS, was an Embraer Brasilia aircraft that crashed near Carrollton, Georgia on August 21, 1995 while on a flight from the Hartsfield-Jackson Atlanta International Airport to Gulfport-Biloxi International Airport in Gulfport, Mississippi...