EASA AD 2021-0289-E
Rotorcraft Flight Manual / Section 2 and 3 — Amendment
Summary
EASA Airworthiness Directive 2021-0289-E is an emergency directive addressing Airbus Helicopters Deutschland GmbH MBB-BK117 C-2, D-2, D3, and D-3m helicopters of all variants and serial numbers. It mandates amendments to the Rotorcraft Flight Manual (RFM) Sections 2 and 3 to incorporate temporary revisions related to the inlet barrier filter (IBF) system. The directive aims to mitigate engine flame out risks caused by partial icing of the IBF engine intakes during operations in falling snow.
What Changed
This directive requires operators to amend the applicable Rotorcraft Flight Manual by incorporating specific temporary revisions that impose limitations on the IBF system, including restrictions on flying in falling or blowing snow. It also allows modification of helicopters without the IBF system to install it, reclassifying them accordingly, and provides instructions for de-installing the IBF system with corresponding RFM updates. These changes are interim safety measures pending further investigation.
Why It Matters
The directive addresses a critical safety issue where engine flame outs have occurred due to partial icing of the IBF intakes, which can lead to loss of helicopter control and potential injury or damage. Compliance ensures that flight crews are informed of operational limitations to prevent such incidents. Maintenance and compliance teams must update manuals and manage modifications to maintain airworthiness and regulatory compliance.
What To Do
Operators of Group 1 helicopters with the IBF system must amend the Rotorcraft Flight Manual within 14 days or 40 flight hours from 27 December 2021, whichever comes first, and inform all flight crews. Group 2 helicopters may install the IBF system using the specified service bulletins and concurrently update the RFM. Helicopters that have the IBF system removed must update the RFM accordingly. All actions must follow the instructions detailed in the directive and referenced documents.
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