AD 73-21-02

73-21-02 BEECH: Amdt. 39-1733. Applies to Models 95-C55, 95-C55A, D55, D55A, E55 and E55A (Serial Numbers TE-1 through TE-874, TE-877 through TE-879, TE-881 and TE- 883 through TE-885); Models 58 and 58A (Serial Numbers TH-1 through TH-269 and TH-272) airplanes, irregardless of time in service.

Compliance: Required as indicated unless already accomplished.

To preclude failure or leakage of the flexible hose assemblies between the firewall and engine fuel injection system pump which could release fuel within the engine compartment or adversely affect engine operation, accomplish the following:

A) Within 50 hours' time in service after the effective date of this AD, on those airplanes which have the Stratoflex P/N 156001-8D0100 hose assemblies installed between the firewall and engine fuel injection pump, replace the hose with a Beech P/N 58-920035-(-1), (-5), or (-7) or (-9) or (-11) or field fabricated equivalent of the proper length as determined by the measurementprocedure contained in Paragraph C of this AD.

B) Within 25 hours' time in service after the effective date of this AD, on those airplanes which have Stratoflex P/N 130001-8D0090 or Beech P/N 58-920035-1 hose assemblies installed either in compliance with AD 73-13-03 or by the manufacturer, visually inspect these hoses per instructions contained in Beech Service Instruction No. 0409-282, Rev. II, Part III, to determine whether they are of the proper length for the location in which they are installed. If the above mentioned Service Instruction is unavailable or the inspection outlined is inconclusive, the acceptability of the installed hose may be determined using the measurement procedure contained in Paragraph C of this AD.

1) Prior to further flight, replace any hose having excessive or insufficient length with a Beech P/N 58-920035-(-1), (-5), or (-7) or (-9) or (-11) or field fabricated equivalent hose of the correct length as determined by the procedure contained inthis AD.

C) Establish the required hose length as follows:

1) Using a P/N 58-920035-1 hose assembly or equivalent, attach one end of the fuel hose to the fuel pump fitting and align the free end of the hose assembly beside the forward left side of the 45-degree firewall fitting.

2) Compare the flare mating surfaces in the hose fitting and the fitting on the firewall to determine the length required. Hose length is critical. Excess length of 1/8 inch -0 plus 1/8 inch will provide the bow necessary for flexing during engine operation. Beech P/N 58- 920035 hose assemblies are available in 1/8-inch length increments.

NOTE: Equivalent hose assemblies may be fabricated to the desired dimensions using Stratoflex Bulk Hose 130-8 and P/N 712-8D fittings following instructions contained in Stratoflex Catalog 103 or equivalent FAA-approved procedures. Stratoflex hose, fittings, and catalogs are obtainable from Stratoflex, Inc., 220 Roberts Cutoff, P.O. Box 10398, Fort Worth, Texas 76114. Aeroquip Type 303 hose is not an acceptable substitute.

Beechcraft Service Instruction No. 0409-282, Rev. II or later approved revisions cover this subject.

This AD supersedes AD 73-13-03 (Amendment 39-166).

This AD becomes effective October 12, 1973.