Boeing 737-890 (WL), N516AS, accident occurred on August 20, 2023, at Santa Ana-John Wayne International Airport (SNA/KSNA), Santa Ana, California

Investigator In Charge (IIC): Hauf, Michael

Additional Participating Entities:

• Rick Domingo; Alaska Airlines; Seattle, WA 
• Nathan Williams; Boeing Commercial Airplanes 
• Mitch Mitchell; FAA; DC 
• Fred Baisch; AMFA 
• Marc Henegar; ALPA 

https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/192903/pdf

https://data.ntsb.gov/Docket?ProjectID=192903

http://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=N516AS

Alaska Airlines

• Location: Santa Ana, California 
• Accident Number: DCA23FA417 
• Date & Time: August 20, 2023, 23:15 Local 
• Registration: N516AS 
• Aircraft: Boeing 737-890 
• Aircraft Damage: Substantial 
• Defining Event: Sys/Comp malf/fail (non-power) 
• Injuries: 112 None 
• Flight Conducted Under: Part 121: Air carrier - Scheduled

This accident occurred when the left main landing gear (MLG) of an Alaska Airlines Boeing 737- 800 collapsed during landing. Postaccident examination revealed that the aft trunnion pin in the left MLG failed during landing due to a fatigue fracture. The fracture initiated from a small intergranular region below the external chromium electroplated layer. The fatigue crack, which had propagated to a depth of 0.144 inches, was large enough to cause the remaining material to fracture in tensile or upward-bending overstress during landing, resulting in the collapse of the left MLG.

Further examination of the aft trunnion pin revealed that the intergranular region where the fatigue crack initiated was located along an area with a darker visual contrast following temper etch and metallographic inspections. This region also showed an elevated reading from a Barkhausen noise inspection. The elevated readings and area of visual contrast were consistent with the area being exposed to higher temperatures becoming softer than the surrounding material. The heat exposure most likely occurred as part of the excessive grinding of the surface, performed during the maintenance overhaul of the pin that occurred on July 5, 2018, as part of the overhaul of the left MLG assembly. This area was subject to grinding to first remove the original chromium layer, and then a second grinding after the new chromium layer was applied to bring the trunnion pin into specified dimensions.

The over-tempered region and the surrounding material created an area of intergranular fracture within the material in the area where grinding had occurred. The investigation considered whether the formation of this area could have occurred during the baking and stress relief processes following aggressive grinding during the chromium removal step of the overhaul. However, after removing the chromium electroplating layer, the temper etch inspections did not detect any grinding burns. Because a temper etch inspection cannot be used after the chromium lectroplating layer was reapplied, the grinding burn likely occurred during machining after the new chromium layer electroplating process.

At the time of the left MLG assembly overhaul, the landing gear assembly had accumulated 11,116 landing cycles. The overhauled left MLG assembly was installed on the accident airplane on July 17, 2018. Afterward, the left MLG, including the trunnion pin, accumulated an additional 4,710 landing cycles.

A fatigue crack analysis performed on the aft trunnion pin fracture surface showed that the fatigue crack had been present for at least 797 landing cycles. Therefore, the crack was not present when the pin was overhauled in July 2018 but had likely developed later as a result of the grinding performed during the overhaul. Because most of the nondestructive inspection techniques used to detect damage to plated trunnion pins typically rely on identifying cracks, techniques such as magnetic particle inspection and fluorescent penetrant inspection would have been ineffective before crack initiation. However, results of this examination and previous NTSB investigations demonstrate that even relatively mild heat exposure from grinding and/or machining during overhaul can lead to cracking, which can lead to fatigue crack growth and failed landing gear components, as occurred in this accident.

• Probable Cause: 

Maintenance personnel’s excessive grinding of the left main landing gear’s aft trunnion pin during machining, which imparted heat damage to the base metal and led to the fatigue cracking that caused the pin to fracture during landing.

Cessna 208B Super Cargomaster, N9471B, accident occurred on March 14, 2025, at Dallas/Fort Worth International Airport (DFW/KDFW), Dallas, Texas

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.

Aviation Accident Preliminary Report - National Transportation Safety Board

Investigator In Charge (IIC): Fox, Andrew

Additional Participating Entities:

• Michael H. LePore; Federal Aviation Administration - North Texas FSDO; Irving, TX

https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=N9471B

https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/199859/pdf

• Location: Dallas, TX 
• Accident Number: CEN25LA122 
• Date & Time: March 14, 2025, 07:38 Local 
• Registration: N9471B
• Aircraft: Cessna 208B 
• Injuries: 1 None 
• Flight Conducted Under: Part 135: Air taxi & commuter - Non-scheduled

On March 14, 2025, about 0738 central daylight time, a Cessna 208B airplane, N9471B, sustained substantial damage when it was involved in an accident at the Dallas-Fort Worth International Airport (DFW), Dallas, Texas. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 135 positioning flight.

The pilot reported that while holding short of runway 17R a departing Spirit Airlines Airbus A321 airplane was cleared for takeoff on runway 17R. The pilot estimated that the departing Airbus A321 was 1,500 to 2,000 ft down the runway when the air traffic controller cleared her to line up and wait on runway 17R. She completed the pretakeoff checklist tasks before taxiing onto runway 17R. The pilot reported that the airplane’s wing flaps were at 10° due to the gusty wind condition and that she held the airplane’s control yoke to the right (left aileron down and right aileron up) to manage the right quartering headwind as the airplane taxied toward the runway 17R centerline on a 45° intercept.

The pilot reported that as the airplane approached the runway 17R centerline it encountered an “unexpected wind shear and wake turbulence” that caused the airplane to “skid to the left”. She was unable to regain directional control by reducing engine power and applying rudder and right aileron. The strong wind lifted the airplane’s right wing enough to allow the left wingtip to strike the ground, which resulted in an uncontrolled left swerve and a propeller strike. The pilot reported that the airplane pivoted 360° on the left wingtip before it came to rest upright on the airplane’s landing gear and aligned with the runway 17R centerline. The airplane operator reported that the airplane sustained substantial damage to the left wing during the accident.

A postaccident review of Federal Aviation Administration (FAA) air traffic control tower communications and ADS-B data was conducted to establish the sequence-of-events that led to the accident, as depicted in figure 1. At 0737:08, the DFW tower controller cleared Spirit Airlines flight 196, an Airbus A321, to line up and wait on runway 17R. At 1237:41, the tower controller transmitted the current surface wind was 170° at 18 knots, gusting to 27 knots. At 0737:49, the tower controller cleared the Airbus A321 for takeoff on runway 17R. At 0737:55, the tower controller issued a caution for wake turbulence and cleared the Cessna 208B to line up and wait on runway 17R.

Based on reported ground speed and the airplane ground track, at 0738:16, about 740 ft past runway 17R threshold, the Airbus A321 began a takeoff roll. About 0738:30, the Cessna 208B lost directional control as it approached runway 17R centerline about 85 ft past the runway threshold.

According to the FAA Aircraft Registry, the Airbus A321-231 was equipped with two International Aero Engines (IAW) V2533 A5 engines. According to Airbus technical document A321 Aircraft Characteristics - Airport and Maintenance Planning, an Airbus A321 equipped with IAE V2500 series engines set at maximum takeoff power has an exhaust danger area that extends 1,150 ft aft of each engine with no surface wind, as depicted in figure 2. Additionally, an engine exhaust velocity of 30 knots would extend to 575 ft aft of the engine exhaust nozzle with no surface wind. Similarly, without a surface wind, an engine exhaust velocity of 17 knots would extend to 990 ft aft the engine exhaust nozzle. A surface wind would affect the extent of the engine exhaust danger area and velocity profiles.

Diamond DA40 NG Star, N499BW, accident occurred on May 7, 2025, at Raleigh Executive Jetport (KTTA), Sanford, North Carolina

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.

Aviation Accident Preliminary Report - National Transportation Safety Board

Investigator In Charge (IIC): Boggs, Daniel

Additional Participating Entities:

• Dave Laycock; FAA; Greensboro, NC

https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=N499BW

https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/200131/pdf

• Location: Sanford, NC 
• Accident Number: ERA25LA198 
• Date & Time: May 7, 2025, 16:00 Local 
• Registration: N499BW 
• Aircraft: DIAMOND AIRCRAFT IND INC DA 40 NG 
• Injuries: 2 Serious 
• Flight Conducted Under: Part 91: General aviation - Personal 

On May 7, 2025, about 1600 eastern daylight time, a Diamond Aircraft DA 40 NG, N499BW, was substantially damaged when it was involved in an accident near Sanford, North Carolina. The pilot and passenger were seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

According to the passenger, who also served as the mechanic for the airplane, he completed the annual inspection on the airplane the week before the accident flight. He further stated that the pilot approached him on the day of the accident and asked him to check his gearbox oil level. The pilot stated it appeared to be lower than normal. The mechanic checked and found the oil plug gasket had a tear in it and replaced the gasket with a new one. He then cleaned and ran the engine to check for leaks. The engine check was good, and the pilot asked the mechanic to go for a test flight around the airport traffic pattern with him for a touch-and-go landing, and then a full-stop landing.

They departed runway 21 at Raleigh Executive Jetport at Sanford-Lee County Airport (TTA), Sanford, North Carolina. Runway 21 was 6,501 ft long, 100 ft wide, and consisted of asphalt. They circled around to perform a touch-and-go landing on runway 21; however, before landing the pilot decided to do a “go around” and leveled off the airplane above the runway. As they were flying down the runway, the engine “popped” like a “backfire” and the pilot tried to land on the remaining runway. They were going too fast and did not have enough runway length left.

The pilot bounced the airplane twice and said they were going to go around. The pilot applied engine power, and the mechanic heard the engine rpm increase. Then the pilot turned the airplane left and they “fell” and impacted the ground. He did not recall anything after that. 

Due to his injuries, the pilot was unable to provide a statement.

The wreckage has been retained for further examination.

Aeroplane Manufactory Chinook Plus 2, N3300K, fatal accident occurred on May 16, 2025, near Alexandria Field Airport (N85), Pittstown, New Jersey

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.

Aviation Accident Preliminary Report - National Transportation Safety Board

Investigator In Charge (IIC): Gretz, Robert

Additional Participating Entities:

• Michael Richert; FAA/FSDO; Allentown, PA

https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=N3300K

https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/200165/pdf

• Location: Pittstown, NJ 
• Accident Number: ERA25FA202 
• Date & Time: May 16, 2025, 16:42 Local 
• Registration: N3300K 
• Aircraft: HARTEVELD DREW J CHINOOK PLUS 2 
• Injuries: 1 Fatal 
• Flight Conducted Under: Part 91: General aviation - Personal

On May 16, 2025, about 1642 eastern daylight time, an experimental, amateur-built Chinook Plus 2, N3300K, was destroyed when it was involved in an accident near Pittstown, NJ. The private pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

A witness at the airport was a friend of the accident pilot and was standing near his hangar at the time of the accident takeoff. He stated that the pilot had been training in a Piper J3, but did not have any flight experience in the make and model accident airplane. He further stated that the takeoff was the pilot’s first flight in the airplane. Just prior to the takeoff, the pilot performed either a takeoff attempt or a high-speed taxi on runway 26. During that run, the pilot lost control of the airplane and it ground looped on grass off the left side of the runway, but did not sustain damage. The pilot then taxied back to the beginning of runway 26 and performed the accident takeoff.

During the takeoff, the airplane traveled on the ground about halfway down the 2,550-ft-long asphalt runway, which was much more than is required for liftoff. The airplane drifted left again, struck and severed a runway light with its left wing strut. The pilot continued the takeoff, climbed, and performed two orbits around the airport, before descending vertically to the accident site.

The wreckage came to inverted in a wooded area about 1/2-mile north of the airport, oriented on a magnetic heading of 135°. A postcrash fire had consumed a majority of the wreckage. All four corners of the airplane were identified, and no debris path was observed. One treetop near the wreckage had been severed. The empennage remained partially intact and crushed, with the rudder and elevator remaining attached. Flight control continuity for the elevator and rudder were confirmed from the control surfaces to the cockpit area, which had been consumed by fire, and cable breaks exhibited broomstraw features. The left wing had been consumed by fire and the frame was resting vertically against a tree. The right wing remained intact and inverted. Both ailerons remained attached to their respective wing. The aileron control cables had been pulled from both wings and were not identified.

Review of the airframe and engine lookbook revealed that the pilot completed assembly of the airplane from a kit in 2025 and it was issued an experimental airworthiness certificate on April 29, 2025. The airplane was equipped with a Rotax 912, 80-hp engine, driving a GCS Systems three-blade wooden propeller. As of an engine logbook entry dated December 12, 2024, the engine had accrued 11.5 hours since new, consistent with ground runs.

The engine came to rest inverted and remained intact. All three propeller blades remained attached to the hub. Two blades were undamaged, and one was partially separated and remained buried in the ground. The crankshaft was not seized and could be rotated 45° in each direction, with restriction due to the propeller blade buried in the ground.

Review of the private pilot’s logbook revealed that he had accrued 443 total hours of flight experience, with his last flight on May 11, 2025, in a Piper J3. There was no record of any flight experience in the make and model accident airplane.

The wreckage was retained for further examination.