ATSB flags possible cause of DA42 Parafield Airport crash

By Andrew Curran.

The Australian Transport Safety Bureau (ATSB) says the failure of a nose landing gear actuator rod is a possible cause of a fatal aircraft crash at Adelaide’s Parafield Airport (YPPF) in April.

This week, the safety regulator released its preliminary findings into the April 29, 2026, accident involving a Diamond DA42 training aircraft that killed the instructor and trainee pilot on board and injured nine people on the ground.

The aircraft, VH-YQP (MSN 42.213), entered a steep descent shortly after take-off before crashing into a flying school classroom and hangar facility.

“ATSB transport safety investigators’ examination of the aircraft wreckage identified that the nose landing gear actuator rod had fractured,” said ATSB Chief Commissioner Angus Mitchell.

“The failure of a nose landing gear actuator rod, as was found in this accident, is known to have caused in-flight controllability issues with this aircraft type in the past, and is one of a number of scenarios, including loss of engine power in one of the aircraft’s engines, that the ATSB investigation is examining,” added Mitchell.

Aircraft enters into a steep descent shortly after take-off

The initial analysis revealed that the instructor radioed advising of an engine failure just 27 seconds after take-off while the aircraft was at 115 feet. Witnesses on the ground reported that the left engine did not appear to be operating and that the left propeller was rotating slowly.

Several seconds later, the aircraft pitched up and banked left. It continued to turn with the left wing down. Fourteen seconds after the radio call, at approximately 165 feet and travelling at an estimated 90 knots, the aircraft entered a steep descent. Photographs show that the aircraft’s main landing gear had retracted, but the nose landing gear remained extended.

In the wake of the crash, examination of the wreckage identified that the nose landing gear actuator rod end had fractured, detaching the actuator from the lever arm on the gear leg.

While metallurgical assessment of the component is ongoing, preliminary examination of the rod end by the ATSB identified indications of progressive fatigue cracking.

“While we have determined the existence of a fatigue crack leading to a failure of the rod, and its potential impact on the rudder controls, we need to follow our evidence examination and analysis processes to determine all of the factors that contributed to this tragic accident,” said Mitchell.

“Importantly, our on-site examination identified that the left engine was not showing signs of producing power on impact, and that the left propeller was in the feathered position,” he added.

“While the left engine post-impact observation may be consistent with an actual engine failure, it may equally be indicative of an assumed or simulated engine failure.”

Wreckage of the Diamond DA42 in the Parafield Airport hangar. Photo: ATSB.

Problems with the left engine

The initial investigation found that the left propeller was in the feathered position and the right propeller was in the fine-pitch position. Specifically, investigators noted that “the left engine did not show signs of rotation”.

Examination of the wreckage found:

• The left engine did not show signs of rotation.
• The right engine propeller hub showed signs of rotation.
• The left propeller was in the feathered position and the right propeller was in the fine-pitch position.
• The rudder trim indicator was found in a nose-left position.
• There was fuel in the tanks.
• All major aircraft components were present at the accident site.
• The nose landing gear actuator had separated from the leg.
• Where possible, flight control continuity was observed.

Previous airworthiness directives highlighted nose landing gear actuator rod problems

In 2013, the European Union Aviation Safety Agency (EASA) issued an airworthiness directive regarding Diamond Aircraft Industries aircraft that described bending and, in one case, fracture of the nose landing gear actuator rod end due to cyclic loading caused by interference between the safety washer and the actuator attachment lever.

The directive noted that “due to the nearby steering linkage, a failed rod end bearing with the LDG [landing] switch in the retracted position may cause interference with the rudder control”.

Six years later, in 2019, another EASA airworthiness directive described an event in which the nose landing gear actuator attachment lever failed due to unidentified cracking that occurred in flight.

The bulletin indicated that the fractured nose landing gear actuator, no longer attached to the gear leg, “interacted with the rudder/nose landing gear controls in such a way that the rudder was forced into left-hand deflection”.

In that case, the pilot reportedly regained full rudder control after extending the landing gear.

The fractured actuator rod end. Photo: ATSB

Diamond Aviation Industry aircraft popular at local training schools

Based in Austria, Diamond is a manufacturer of general aviation aircraft and motor gliders. It is a subsidiary of China-based Wanfeng Aviation.

Diamond aircraft are popular in Australia and are widely used by private owners, charter operators and flight training schools. Both the single-engine DA40 and twin-engine DA42 are common training aircraft.

On the day of the accident, the flight was planned to conduct simulated one-engine-inoperative (asymmetric) circuits.

The ATSB says the instructor held a Commercial Pilot Licence (Aeroplane), initially issued in June 2017, with both multi-engine and single-engine aeroplane class ratings. He had logged 2,592.4 hours total flight time, including 607 hours instructing on multi-engine aircraft.

The trainee pilot held a Commercial Pilot Licence (Aeroplane), issued in March 2026, with a class rating for single-engine aeroplanes. He was undergoing training towards a multi-engine aeroplane class rating. The pilot had logged 205.6 hours total flight time, including 16.9 hours on the DA42 type.

“The circumstances of the accident were consistent with a pre-accident fracture of the rod end, resulting in the nose landing gear being observed down while the main landing gear was retracted,” the preliminary report states.

“While it was possible that the separated nose landing gear actuator interfered with the steering/rudder controls, as per the previously reported occurrence described in the Diamond Aircraft Industries mandatory service bulletin, further examination and analysis is required by the ATSB. The ATSB is also considering other scenarios to explain the accident sequence.”

You can read the full preliminary report here.

Photos: Diamond Aircraft Industries, ATSB.

Contact the writer: andrew@aerosouthpacific.com