Supersedes Existing AD Dealing With Tail Rotor Tip Weights

The FAA is superseding a previous AD with an Emergency AD for Bell Helicopter Textron Model 204B, 205A, 205A-1, 205B, 210, 212, 412, 412CF, and 412EP helicopters.

Bell 412 File Photo

The superseding EAD is prompted by another incident in which the tail rotor blade (blade) tip weight separated from a blade during flight causing vibration. This unsafe condition led to the determination that additional blades could be affected and should be added to the applicability. The actions specified by this AD are intended to prevent loss of the blade tip weight, loss of a blade, and subsequent loss of control of the helicopter.

On October 31, 2007, the FAA issued AD 2007-19-53 which requires, before further flight, removing and replacing each affected blade with an airworthy blade. That action was prompted by three reports of blade tip weights being slung from the blades during flights, causing significant vibration.

The FAA says it has reviewed the following revised BHT Alert Service Bulletins (ASBs), all dated November 22, 2010 except where noted otherwise. Each Alert Service Bulletin (ASB) contains an RBI letter that adds blade serial numbers to the RBI list.

• No. 204-07-61, Revision A, dated September 19, 2007, for Model 204 helicopters;
• No. 205-07-95, Revision B, for Model 205 helicopters;
• No. 205B-07-46, Revision B, for Model 205B helicopters;
• No. 212-07-125, Revision B, for Model 212 helicopters;
• No. 412CF-07-123, Revision B, for Model 412CF helicopters;
• No. 412-07-123, Revision B, for Model 412 and 412EP helicopters.

The FAA says it is issuing this AD because we evaluated all information and determined the unsafe condition exists and is likely to exist or develop on other helicopters of these same type designs. Since the unsafe condition is likely to exist or develop on other helicopters of these same type designs, this AD requires, before further flight, unless already accomplished, replacing any affected blade with an airworthy blade.

FMI: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgAD.nsf/0/29D12391ECD3F47A862577F50079AB79?OpenDocument