Kawasaki BK 117 Series Helicopters
Kawasaki BK 117 Series Helicopters
Kawasaki BK 117 Series Helicopters
| AD/JBK 117/31 | Tail Rotor Balance Weights | 3/2009 |
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| Applicability: | All Model BK117 Series helicopters. |
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| Requirement: | Inspect the tail rotor balance weights and control levers in accordance with the instructions of Kawasaki Service Bulletin (SB) No. KSB-117-297 original issue, or later JCAB approved revision.If, during any inspection required by this Directive, damage is detected which exceeds the acceptable limits specified in SB No. KSB-117-297 original issue, or later JCAB approved revision, before further flight, replace the affected components with serviceable parts.Note: JCAB AD TCD-7416-2009 refers. |
| Compliance: | Within 2 months or 100 flight hours after 12 March 2009, whichever occurs first; and thereafter at intervals not to exceed 660 flight hours or 30 months, whichever occurs first. |
| This Airworthiness Directive becomes effective on 12 March 2009. | |
| Background: | During a periodic inspection, corrosion was detected on the tail rotor balance weights in the area of the thread. At advanced stage, this corrosion could possibly destroy the threads. Unless prevented, undetected corrosion on the tail rotor balance weights in the area of the attachment threads could lead to failure of the threads, possible separation of tail rotor parts, and subsequent severe tail rotor vibration. |
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David Punshon
Delegate of the Civil Aviation Safety Authority
22 January 2009