What happened
On 5 April 2026, two pilots were aboard a Piper Seneca PA-34-200T registered ZS-SNR for a post-maintenance test flight departing from Lanseria International Airport (FALA) in Gauteng. The flight was conducted under visual meteorological conditions during the day. After takeoff, the crew performed touch-and-go maneuvers as part of the maintenance check. During the second circuit, pre-landing checks indicated that the landing gear was down and locked, confirmed by three green cockpit lights. Upon touchdown on Runway 25, the main gear made contact first, followed by the nose gear. As the aircraft rolled, the nose landing gear collapsed, causing the nose to pitch down and both propeller blades to strike the runway surface. The aircraft sustained substantial damage to the nose cone and propellers, but no injuries were reported.
The investigation
SACAA AIID examined the aircraft after it was recovered to the owner's hangar. Inspectors found that all rivets connecting the actuator mount assembly bracket and the lower drag link mount to the bulkhead at station 49.50 had sheared. This allowed the brackets to move freely against the bulkhead when the gear was extended. The investigation also reviewed the aircraft's history, noting a previous accident on 25 March 2025 where the nose gear collapsed due to an actuator leak. Although repairs were made and the aircraft passed inspections, including eddy current testing, the manufacturer was not consulted for additional technical advice regarding the structural event.
Findings
The primary cause was the failure of previously damaged actuator mount bracket rivets at fuselage station 49.50. This damage, likely sustained during the March 2025 accident, created a latent defect that was not detected during subsequent inspections. During the test flight, these weakened rivets failed, leaving the bracket unsecured. Consequently, the nose landing gear drag braces could not achieve the over-centre locked position. Despite this mechanical failure, the down lock switches still activated the green 'down and locked' indications in the cockpit and shut off the hydraulic pump. With no effective mechanical lock or hydraulic support, the gear collapsed under the aircraft's weight during landing.
Safety action
SACAA AIID issued a safety message reminding operators and maintenance organizations that standard manufacturer procedures may be insufficient after major structural events. When an aircraft experiences a structural incident not explicitly covered in maintenance manuals, the manufacturer should be contacted for specific technical advice to ensure safe return to service.