What happened
On August 23, 2011, at 17:40 UTC, a Piper PA 34-200T (registration OK-ALY) was performing a repositioning flight from Roudnice nad Labem (LKRO) to Vodochody (LKVO) for maintenance. The flight was intended to move the aircraft to an authorized maintenance organization following a previous engine power issue.
During the approach to runway 10, the pilot attempted a shorter landing by increasing engine power and applying significant elevator input. At approximately 15 meters above the runway threshold, the aircraft experienced a sudden sink rate. The pilot responded by increasing power, but the aircraft made a heavy touchdown on the main gear followed immediately by the nose gear. The impact was severe enough to cause the nose gear to retract. As the aircraft continued along the runway, the nose of the plane descended, leading to both propellers striking the ground and the engines being forcibly stopped. The aircraft traveled 276 meters from the initial contact point before coming to a halt.
The investigation
The ÚZPLN investigation examined the aircraft's mechanical state, the pilot's actions, and the maintenance history. Investigators found that while a previous incident on July 18, 2011, had resulted in a maintenance requirement, the aircraft had not been officially released for flight by the maintenance organization for this specific repositioning leg, as no release entry was found in the aircraft logbook.
Technical analysis of the landing gear revealed that the force from the hard impact traveled through the gear leg and hydraulic cylinder to the mounting bracket. The impact was so intense that it sheared all rivets securing the bracket to the fuselage, causing the bracket to shift 49 mm. This movement displaced the drag brace lock linkage, causing the brace to fail into the unlocked position. Subsequent vibrations and the aircraft's weight then caused the nose gear to retract.
Findings
- The primary cause of the accident was a hard landing that triggered the nose gear collapse.
- The aircraft was technically unserviceable for this flight leg as it lacked the necessary maintenance release entry in the logbook.
- The impact caused extensive damage to the airframe, including a ruptured nose cone, torn fuselage bulkheads, and cracked landing gear components.
- Both propellers sustained symmetrical blade deformation due to ground contact.
- The pilot was fully qualified and medically fit, but the high-power, high-sink-rate approach contributed to the severity of the impact.