EASA AD 2021-0155: Rotors Flight Control — Main Rotor Scissors Fittings — Inspection / Replacement

What to do

Operators of Group 1 Cabri G2 helicopters must perform a detailed inspection of affected scissors fittings within 30 flight hours or 30 days after 5 October 2020, followed by repetitive visual inspections every 60 flight hours or 6 months. If cracks are found, the affected assemblies must be replaced before the next flight with serviceable parts or modified assemblies. Additionally, during the next main gearbox overhaul or within 60 months from the AD's effective date, the main rotor hub and swashplate guide must be replaced with assemblies equipped with the improved fittings. Reporting inspection results to Hélicoptères Guimbal is required if discrepancies are detected.

Summary

EASA Airworthiness Directive 2021-0155 is an airworthiness directive addressing the inspection and replacement of main rotor scissors fittings on Hélicoptères Guimbal Cabri G2 helicopters. It applies to all serial numbers of the Cabri G2 and focuses on rotating and non-rotating scissors fittings with Part Number G12-00-200 installed on the main rotor hub and swashplate guide. The directive mandates inspections and eventual replacement of affected parts to ensure continued airworthiness.

What changed

EASA AD 2021-0155 supersedes the previous AD 2020-0199 and retains its inspection requirements while introducing a design modification involving new scissors fittings (P/N G12-00-202) that are not susceptible to stress corrosion cracking. The directive updates the inspection interval from 50 to 60 flight hours and prohibits reinstallation of affected parts on helicopters that have been modified with the new fittings.

Why it matters

This directive is critical for operators and maintenance organizations to prevent potential failure of main rotor scissors fittings caused by corrosion under residual stress, which could lead to loss of helicopter control. Compliance ensures the safety and airworthiness of Cabri G2 helicopters by mandating inspections, reporting, and replacement or modification of affected components. It also provides clear guidance on part installation and maintenance to mitigate risks associated with this unsafe condition.