Document ID: chunk:federal_register_of_legislation:F2006B03867:reg:22:p1
Version: federal_register_of_legislation:F2006B03867
Segment Type: reg
Provision Reference: reg 22 (pt 1/2)
Character Range: 9327–12480

22            TAILCONE

              Figure 2

            Note: FAA AD 2002 -21-13 Amdt 39-12920 refers.

  Compliance: Requirements 1, 2, and 3: Within 10 hours time in service after 8 July 1998.

            Requirement 4: Within the next 100 hours time in service after the last inspection required by FAA AD 94-20-04 (AD/BEECH 35/58 Amdt 4) or within 25 hours time in service after 23 January 2003, whichever occurs later, and thereafter at intervals not to exceed 100
            hours time in service. Accomplish any repairs, replacements, and adjustments before further flight after the applicable inspection.

            Requirement 5: Within the next 100 hours after 23 January 2003, unless already accomplished as previously required by AD/BEECH 35/58 Amdt 4. Correct any discrepancies before further flight after the verification.

            Requirement 6: Within 3 years after 23 January 2003, unless already accomplished. Accomplish any repair or replacement before further flight after the inspection. Accomplish any ruddervator rebalancing before further flight after the inspection, unless previously accomplished within the last 100 hours time in service, and thereafter when the ruddervators are repaired or repainted (even if stripes are added or paint is touched up).

            The compliance time for Requirements 1, 2, and 3 remains unchanged by this issue. This Amendment becomes effective on 23 January 2003.
            Background: The FAA received reports of several incidents of in-flight vibrations on Beech Model 35, A35, B35, and 35R aircraft. These incidents are unrelated to AD 94-20-04 ( AD/BEECH 35/58 Amdt 4), which currently requires, among other things, balancing the ruddervators (off the aircraft) anytime the ruddervator is repaired or repainted. Of the 10 incidents since AD 94-20-04 became effective, 7 of the affected aircraft had ruddervators that were balanced and 3 had ruddervators that were out-of-balance.

            Post-flight inspections of the aircraft involved in the incidents have revealed cracked bulkheads and wrinkled skin in the aft fuselage; and broken spars, broken hinges, and bent skin on the stabilisers and ruddervators.

            Model 35, A35, B35, and 35R aircraft are equipped with "V-tails" that have a narrow chord stabiliser without reinforcing cuffs. The FAA's preliminary investigation reveals the possibility of an unstable flutter mode in the 160 to 170 MPH range for the affected aircraft. The unstable mode is not likely to occur on other Beech aircraft models with "V-tail" configurations.

            Amendment 1 is issued in response to a new FAA AD which was prompted by the manufacturer developing inspection and modification procedures that, when accomplished on the affected aircraft, will eliminate the need for the operating limitations. This Directive retains the operating limitations for the affected aircraft until the recently developed inspection and modification procedures are accomplished. This Directive also requires repetitive inspections of the fuselage structure.

            The original issue of this Airworthiness Directive became