Alpi Pioneer 300 Landing Gear Collapse, Fenland Airfield
The Alpi Pioneer 300 aircraft landed on Runway 26 at Fenland Airfield.
While taxiing after landing, the left main landing gear of an Alpi Pioneer 300 collapsed due to the failure of the swinging leg, causing the left wing to contact the ground. The leg had fractured in overload initiating close to the weld between the swinging leg and its pivot tube.
As a result of this [AAIB] investigation, the Light Aircraft Association (LAA) are reviewing design and manufacturing aspects of the type’s landing gear, including whether ongoing maintenance action is required.
The crack initiated from the interface of pivot tube to swinging leg tube. Poor weld quality between two components can act as a stress raiser at the interface and could serve to locate a crack. If the landing gear was subjected to a heavy landing or an element of lateral loading during a crosswind landing, this could increase the stress at the interface between the swinging tube and the pivot tube and cause a crack to initiate and propagate rapidly.
As a result of this investigation, the LAA are reviewing the design and manufacturing aspects of the Alpi Pioneer 300 landing gear, including whether ongoing maintenance action is required.
The pilot did not recall any particularly heavy landings, however, did say that the aircraft often flew from grass airfields where the surface condition can be rougher and may have been sufficient to initiate a crack.
Although the owner had inspected the landing gear components recently it would be difficult to inspect as the downtube of the main landing gear strut partially covers the location of the crack initiation.
Content/photo source/credit: AAIB Bulletin 8/2023 (Air Accident Investigation Branch), “AAIB investigation to Alpi Pioneer 300, G-IPKA,” published August 10, 2023.