Main Rotor Drive — Main Gearbox Top Sensor / Main Rotor Mast Lubrication System — Inspection
- Published
- Effective
- Deadline
- Replaces
- 2019-0169
AI-generated summary of the official EASA document. Verify against the PDF before acting.
What to do
Operators must inspect Group 1 helicopters within 400 flight hours or 6 months after 30 July 2019, and Group 2 helicopters within 10 flight hours after the effective date, with ongoing inspections at specified intervals. If foreign objects or lubrication issues are found, affected main gearboxes and main rotor mast assemblies must be replaced before the next flight. Installation of only serviceable main gearboxes is permitted from the effective date of the AD.
Summary
EASA Airworthiness Directive 2020-0042 is an airworthiness directive affecting all Airbus Helicopters EC 175 B models. It mandates inspections of the main gearbox top sensor and the main rotor mast lubrication system to detect foreign object debris that could cause mast bearing seizure and potential loss of helicopter control. The directive includes specific inspection procedures and corrective actions to ensure continued airworthiness.
What changed
EASA Airworthiness Directive 2020-0042 supersedes AD 2019-0169 and expands inspection requirements to additional main gearboxes not covered previously. It introduces repetitive inspections for a wider population of main gearboxes and requires a one-time inspection of the main rotor mast lubrication system, with corrective actions based on inspection findings. This AD partially retains previous inspection requirements while adding new compliance measures.
Why it matters
This directive is critical for operators and maintenance organizations to prevent potential loss of helicopter control due to mast bearing seizure caused by foreign object debris in the main gearbox. Compliance ensures safety by detecting and correcting lubrication system contamination early. It also affects parts installation policies and maintenance scheduling, impacting operational continuity and regulatory compliance.
More for Airbus Helicopters EC175
All 73- EASA AD 2026-0179Tail Rotor – Tail Rotor Blade – Service Life Limit Amendment / ReplacementSep 18, 2026
- EASA PAD 26-090Tail Rotor – Tail Rotor Blade – Service Life Limit Amendment / ReplacementJul 24, 2026
- EASA AD 2026-0110[Correction] Fuselage – Screws and Nuts installed on Firewalls – InspectionJun 10, 2026
- EASA AD 2026-0039Time Limits / Maintenance Checks — Airworthiness Limitations Section — AmendmentFeb 27, 2026
- EASA PAD 26-026
Get the next one by email
New ADs and bulletins for Airbus Helicopters EC175 and Helicopters EC 175 B, summarized like this page, every Monday.