Main rotor blade delamination detected — Robinson R44 series

Summary

During a post-flight inspection at Karratha, the pilot of a Robinson R44 Raven II detected a soft area on the main rotor blade surface consistent with internal delamination. The aircraft was immediately grounded and the blade removed for inspection. No in-flight anomaly had been noted.

Investigation Findings (4)

1. 01Delamination was confirmed at the root end of the main rotor blade, initiating at a disbond in the glass fibre laminate.
2. 02The blade had accumulated 1,240 hours TIS, well within the 2,200-hour TBO.
3. 03Robinson Helicopter Company investigation identified a manufacturing-related resin void introduced during blade production.
4. 04The aircraft was returned to service after blade replacement with an enhanced ultrasonic inspection sign-off.