Airworthiness Directive 2004-22-11
one-timeAirworthiness Directives; Eurocopter Deutschland GmbH Model EC135 P1, P2, T1, and T2 Helicopters
What this AD requires
This amendment supersedes an existing airworthiness directive (AD) for Eurocopter Deutschland GmbH (Eurocopter) Model EC135 P1, P2, T1, and T2 helicopters. That AD currently requires adding the AD or a statement to the Rotorcraft Flight Manual (RFM) informing the pilot to reduce power and land as soon as practicable if a thump-like sound followed by an unusual vibration occurs during flight. That AD also requires visually inspecting the main rotor drive torque strut assembly (strut) for a crack or a break, recording the inspections in the historical or equivalent record, re-marking and relocating the strut, as appropriate, and replacing any unairworthy strut with an airworthy strut. Also, that AD establishes life limits for certain struts and revises the life limit for other struts. This amendment requires the same actions as the existing AD except that it changes the visual inspection from a one-time inspection to daily inspections; reduces the life limit for aluminum struts; and eliminates the once-only transfer and remarking of certain struts. This amendment is prompted by an incident in which a pilot felt an in-flight increase in vibration and subsequent discovery of a failed strut. The actions specified by this AD are intended to prevent failure of a strut and subsequent loss of control of the helicopter.
Which aircraft AD 2004-22-11 applies to
Applies only to EC135 P1, P2, T1, and T2 helicopters with main rotor drive aluminum torque strut assembly P/N L633M1001-103 or L633M1001-105 installed.
Whether AD 2004-22-11 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.
How AD compliance is recorded
A valid compliance record (14 CFR 43.9) states:
Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.
Look up a tail number →Read the full directive (Federal Register)Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.