Air Crash Daily | Atlantic Southeast Airlines Flight 2311 News Reports @AirCrashDaily | Uploaded August 2024 | Updated October 2024, 1 hour ago.
CHAPTERS
0:00 1
1:38 2 (Includes ATC Recording)
ATC Recording: youtu.be/mZLBTHOcrnE?si=Cw47RZ9XYdD3wclL
Accident Description:
instagram.com/p/CqqMbayvQZA/?igsh=MTcyMGJiYnk3bWVzMQ==
๐๐๐น๐ฎ๐ป๐๐ถ๐ฐ ๐ฆ๐ผ๐๐๐ต๐ฒ๐ฎ๐๐ ๐๐ถ๐ฟ๐น๐ถ๐ป๐ฒ๐ ๐๐น๐ถ๐ด๐ต๐ ๐ฎ๐ฏ๐ญ๐ญย was a scheduled domestic passenger flight from Atlanta to Brunswick, operated by an Embraer EMB-120 Brasilia (Reg. N270AS) on ๐๐ฝ๐ฟ๐ถ๐น ๐ฑ, ๐ญ๐ต๐ต๐ญ.
The flight was initially scheduled to depart Atlanta at 13:24 EST and be operated by an EMB-120 Brasilia (Reg. N228AS). Because of mechanical problems an airplane change was made to N270AS. The flight departed Atlanta at 13:47 and arrived in the Brunswick area about 14:44. At 14:48 the flight was cleared for a visual approach to runway 07. The plane had just turned from base leg to final approach when the plane was seen to pitch up about 5ยฐ and roll to the left. The plane then nosed down into the ground, 9,975 feet short of the runway.
Examination of the left propeller components indicated a blade angle of about 3ยฐ, while the left PCU ballscrew position was consistent with a commanded blade angle of 79.2ยฐ. Extreme wear on the PCU quill spline teeth, which normally engaged the titanium-nitrided splines of the propeller transfer tube, was found. The titanium-nitrided surface was much harder and rougher than the nitrided surface of the quill. Therefore, the transfer tube splines acted like a file and caused abnormal wear of the gear teeth on the quill. Wear of the quill was not considered during the certification of the propeller system.
๐ฃ๐ฟ๐ผ๐ฏ๐ฎ๐ฏ๐น๐ฒ ๐๐ฎ๐๐๐ฒ:
"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 Standard and the approval of the design by the Federal Aviation Administration. 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."
CHAPTERS
0:00 1
1:38 2 (Includes ATC Recording)
ATC Recording: youtu.be/mZLBTHOcrnE?si=Cw47RZ9XYdD3wclL
Accident Description:
instagram.com/p/CqqMbayvQZA/?igsh=MTcyMGJiYnk3bWVzMQ==
๐๐๐น๐ฎ๐ป๐๐ถ๐ฐ ๐ฆ๐ผ๐๐๐ต๐ฒ๐ฎ๐๐ ๐๐ถ๐ฟ๐น๐ถ๐ป๐ฒ๐ ๐๐น๐ถ๐ด๐ต๐ ๐ฎ๐ฏ๐ญ๐ญย was a scheduled domestic passenger flight from Atlanta to Brunswick, operated by an Embraer EMB-120 Brasilia (Reg. N270AS) on ๐๐ฝ๐ฟ๐ถ๐น ๐ฑ, ๐ญ๐ต๐ต๐ญ.
The flight was initially scheduled to depart Atlanta at 13:24 EST and be operated by an EMB-120 Brasilia (Reg. N228AS). Because of mechanical problems an airplane change was made to N270AS. The flight departed Atlanta at 13:47 and arrived in the Brunswick area about 14:44. At 14:48 the flight was cleared for a visual approach to runway 07. The plane had just turned from base leg to final approach when the plane was seen to pitch up about 5ยฐ and roll to the left. The plane then nosed down into the ground, 9,975 feet short of the runway.
Examination of the left propeller components indicated a blade angle of about 3ยฐ, while the left PCU ballscrew position was consistent with a commanded blade angle of 79.2ยฐ. Extreme wear on the PCU quill spline teeth, which normally engaged the titanium-nitrided splines of the propeller transfer tube, was found. The titanium-nitrided surface was much harder and rougher than the nitrided surface of the quill. Therefore, the transfer tube splines acted like a file and caused abnormal wear of the gear teeth on the quill. Wear of the quill was not considered during the certification of the propeller system.
๐ฃ๐ฟ๐ผ๐ฏ๐ฎ๐ฏ๐น๐ฒ ๐๐ฎ๐๐๐ฒ:
"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 Standard and the approval of the design by the Federal Aviation Administration. 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."
