Airworthiness Directive · Amendment 39-18762 · Main rotor blades
Robinson Helicopter Company Helicopters
This AD applies to Robinson Helicopter Company (Robinson) Model R44 and R44 II helicopters with a main rotor blade (MRB) part number (P/N) C016-7, Revision AA through AE installed; and Model R66 helicopters with a MRB P/N F016-2, Revision A through E, installed; certificated in any category.
We are adopting a new airworthiness directive (AD) for Robinson Helicopter Company (Robinson) Model R44, R44 II, and R66 helicopters. This AD requires inspecting the main rotor blade (MRB). This AD was prompted by a determination that some MRBs may have reduced blade thickness due to blending out corrosion. The actions are intended to prevent the unsafe condition on these products.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
Within 100 hours time-in-service or at the next annual inspection, whichever occurs first:
(1) Clean each MRB in the area depicted in Figure 1 of Robinson R44 Service Bulletin SB-89, dated March 30, 2015 (SB-89), or Robinson R66 Service Bulletin SB-13, dated March 30, 2015 (SB-13), as applicable to your model helicopter.
(2) Using 10X or higher power magnification and a light, visually inspect the upper and lower MRB surfaces and trailing edge as depicted in Figure 1 of SB-89 or SB-13, whichever applies to your helicopter, for a crack, a nick, a scratch, a dent, or corrosion. If there is a crack, a nick, a scratch, a dent, or any corrosion, repair the MRB to an airworthy configuration if the damage is within the maximum repair damage limits or remove the MRB from service.
(3) Alter the MRB in accordance with Compliance Procedure, paragraphs 4 through 19, of SB-89 or SB-13, as applicable to your model helicopter. Equivalent tubing may be used for R7769-1 and R7769-6 tubes. Power tools may not be used for this procedure.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
