However, the CFM56 windmill relight envelope is relatively small when compared to other turbofan engines of the same class. The line between the airports does This information is not presented as the Flight Safety Foundation or the Aviation Safety Networks opinion as to the cause of the accident. At certain combinations of fan rotational speeds and airplane speeds, a higher concentration of hail can enter the engine, as compared to rain at the same conditions. The flight crew attempted to avoid the most severe storm cells but penetrated momentarily into massive precipitation.At approximately 16,000 feet, the airplane encountered 30 seconds of heavy hail, resulting in both engines experiencing a simultaneous complete power loss, following a thrust roll-back. These included:Spinner profile change from conical to a combination elliptical and conical (spinner shape called coniptical) to guide the hail radially outwardCutback splitter that allows more ingested rain and/or hail to be centrifuged out by the fan rotor, away from the core, and into the fan bypass flowIncreased number of variable bleed valve (VBV) doors that allowed additional rain and/or hail to be extracted from the core flow path at low engine rotational speedsAdaptive engine start logic for Full Authority Digital Electronic Controlled (FADEC) engines (the TACA engines were not FADEC controlled).
For the TACA event, the CFM56 engine windmill in-flight restart envelope, like other turbofan engines, is based on starts in clear air conditions. The flight crew, recognizing there was no engine thrust response to throttle commands, elected to shut down both engines and prepare for an emergency landing.The flight crew realized that a landing was not possible at the airport and started preparations to ditch. However, certification testing conducted on the CFM56 engine was performed with a substantially greater amount of water than was required by the regulations. Red areas indicate the most intense precipitation and are to be avoided. These include: When the water-to-air ratio becomes sufficiently high, it overcomes the fuel-to-air ratio required for stable combustion, and subsequently results in an engine flame-out. The airplane, a brand new Boeing 737-300 with 38 passengers and a crew of seven on board, departed as scheduled from Belize City, and the flight was uneventful until descent into New Orleans.PROBABLE CAUSE: "A double engine flameout due to water ingestion which occurred as a result of an inflight encounter with an area of very heavy rain and hail.
Once the engine fails, it cannot be restarted until the water-to-air ratio decreases to a point where the fuel-to-air ratio can once again maintain combustion.At the time the CFM56 engine was evaluated, the FAA engine hail ingestion requirements were focused on foreign object damage (FOD) to engine hardware and not engine operability effects. Have fun watching.
TACA International Airlines Flight 110 was a regularly scheduled passenger flight between San Salvador, El Salvador, to New Orleans, Louisiana, USA with an en route stop in Belize City, Belize. It is preliminary and is based on the facts as they are known at this time.TACA International Airlines Flight 110 was a regularly scheduled passenger flight between San Salvador, El Salvador, to New Orleans, Louisiana, USA with an en route stop in Belize City, Belize. To watch this documentary please click the title or image above. Adaptive start logic improves the starting performance, and reduces the risk of engine damage during a start sequence.Introduced improvements to the flow path contour (i.e., S - shape turn) to increase the effectiveness of VBV doors to remove material from the core flow path. Displays typically show green for lowest intensities of weather, graduating to amber and red as intensity increases. Although these test demonstrated a 400% margin, they were later found to be incorrect due to the testing methods involving low airplane speed and high engine rotational speeds which tended to shield the core (i.e., centrifuging of water away from the core).Following the TACA event, CFMI conducted an extensive investigation that included multiple engine tests and detailed analysis. It was believed that the primary threat posed by hail was foreign object damage.
However, investigators learned that hail behaves significantly different than water when passing through an engine fan and entering the core of a turbofan engine.Severe hail ingestion into an engine can cause adverse engine operation, such as flameout or roll-back, due to an excessive water-to-air ratio in the engine core.
For the TACA event, the CFM56 engine windmill in-flight restart envelope, like other turbofan engines, is based on starts in clear air conditions. The flight crew, recognizing there was no engine thrust response to throttle commands, elected to shut down both engines and prepare for an emergency landing.The flight crew realized that a landing was not possible at the airport and started preparations to ditch. However, certification testing conducted on the CFM56 engine was performed with a substantially greater amount of water than was required by the regulations. Red areas indicate the most intense precipitation and are to be avoided. These include: When the water-to-air ratio becomes sufficiently high, it overcomes the fuel-to-air ratio required for stable combustion, and subsequently results in an engine flame-out. The airplane, a brand new Boeing 737-300 with 38 passengers and a crew of seven on board, departed as scheduled from Belize City, and the flight was uneventful until descent into New Orleans.PROBABLE CAUSE: "A double engine flameout due to water ingestion which occurred as a result of an inflight encounter with an area of very heavy rain and hail.
Once the engine fails, it cannot be restarted until the water-to-air ratio decreases to a point where the fuel-to-air ratio can once again maintain combustion.At the time the CFM56 engine was evaluated, the FAA engine hail ingestion requirements were focused on foreign object damage (FOD) to engine hardware and not engine operability effects. Have fun watching.
TACA International Airlines Flight 110 was a regularly scheduled passenger flight between San Salvador, El Salvador, to New Orleans, Louisiana, USA with an en route stop in Belize City, Belize. It is preliminary and is based on the facts as they are known at this time.TACA International Airlines Flight 110 was a regularly scheduled passenger flight between San Salvador, El Salvador, to New Orleans, Louisiana, USA with an en route stop in Belize City, Belize. To watch this documentary please click the title or image above. Adaptive start logic improves the starting performance, and reduces the risk of engine damage during a start sequence.Introduced improvements to the flow path contour (i.e., S - shape turn) to increase the effectiveness of VBV doors to remove material from the core flow path. Displays typically show green for lowest intensities of weather, graduating to amber and red as intensity increases. Although these test demonstrated a 400% margin, they were later found to be incorrect due to the testing methods involving low airplane speed and high engine rotational speeds which tended to shield the core (i.e., centrifuging of water away from the core).Following the TACA event, CFMI conducted an extensive investigation that included multiple engine tests and detailed analysis. It was believed that the primary threat posed by hail was foreign object damage.
However, investigators learned that hail behaves significantly different than water when passing through an engine fan and entering the core of a turbofan engine.Severe hail ingestion into an engine can cause adverse engine operation, such as flameout or roll-back, due to an excessive water-to-air ratio in the engine core.