Commonwealth legislation

AD/BEECH 99/4 - Vertical Stabiliser Main Spar

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Commonwealth

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legislative instrument

Plain English Summary

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This directive requires borescope inspection of the vertical stabiliser main spar flanges and angle doubler on Beechcraft 99 aircraft (serial U‑1 to U‑151) at specified initial and recurring intervals to detect cracking. Owners/operators must arrange and pay for inspections and any repairs; fitting an approved doubler or replacing the stabiliser with specified parts cancels the recurring inspection. It addresses observed spar cracking to reduce structural risk.

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AD/BEECH 99/4 - Vertical Stabiliser Main Spar

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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Beechcraft 99 Series Aeroplanes

AD/BEECH 99/4 Vertical Stabiliser Main Spar 6/95

Applicability: Beech 99, 99A, A99A and B99 aircraft, serial numbers U-1 to U-151.

Requirement: Visually inspect, using a borescope, both flanges of the vertical stabiliser main spar and angle doubler as specified in Beech Service instruction (SI) 0530-134.

Note: FAA AD 90-15-18 refers.

Compliance: Initially inspect before 2000 hours’ time in service or before 50 hours’ time in service after 25 May 1995, whichever occurs last.

Re-inspect at intervals not to exceed 500 hours’ time in service.

Installation of a doubler over uncracked structure in accordance with Beech SI 0530- 134, Fig 3; or stabiliser replacement with P/N 115-640000-605, -607 or -651 cancels the Requirement of this Directive.

Background: Cracking has been experienced in the vertical stabiliser main spar.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/BEECH 99/4 - Vertical Stabiliser Main Spar