AD 77-13-08

77-13-08 BEECH: Amendment 39-2933. Applies to Models 58P and 58PA (Serial Numbers TJ-2 thru TJ-117), 58TC and 58TCA (Serial Numbers TK-1 thru TK-63) airplanes certificated in all categories.

Compliance: Required as indicated, unless already accomplished.

To assure structural integrity of the right and left truss tube assemblies in both the right and left engine nacelles, accomplish the following:

A) On Models 58P and 58PA (S/Ns TJ-2 thru TJ-99), 58TC and 58TCA (S/Ns TK-1 thru TK-54) airplanes that do not have Beech Kit No. 102-9001-1S installed, prior to the next flight (unless previously accomplished in accordance with Beechcraft mailgram dated February 17, 1977) and at each 50 hours' time in service interval thereafter, until Beech Kit No. 102-9001- 1S is installed:

1. Pursuant to Beechcraft Service Instructions No. 0903 or later approved revisions accomplish the following:

a. Referring to Figure 1 of this AD dye penetrant inspect the right truss tubeassembly in both right and left engine nacelles for cracks which initiate from the two rivet holes attaching the turbocharger air intercooler mounting brackets; and

b. Replace any cracked right truss tube assembly prior to the next flight.

2. Pursuant to Beechcraft Service Instructions No. 0903 or later approved revisions accomplish the following:

a. Referring to Figure 1 of this AD visually inspect the left truss tube assembly in both right and left engine nacelles for chafing:

b. Dye penetrant said part for cracks; and

c. Replace any cracked left truss tube assembly and repair or replace any chafed left truss tube assembly prior to the next flight.

B) On Models and serial numbers listed in Paragraph A of this AD that have Beech Kit No. 102-9001-1S installed and on Models 58P and 58PA (S/Ns TJ-100 thru TJ-117), 58TC and 58TCA (S/Ns TK-55 thru TK-63) airplanes, within the next 100 hours' time in service after the effective date of this AD, or within 100 hours' time in service after the last similar inspection accomplished in accordance with Beechcraft Service Instructions No. 0903, whichever occurs first, and at each 100 hours' time in service interval thereafter:

1. Pursuant to Beechcraft Service Instructions No. 0903 or later approved revisions:

a. Remove cowlings from right and left engines;

b. Referring to Figure 1 of this AD visually inspect the right and left truss tube assemblies in both right and left nacelles for cracks, chafing or other signs of structural weakening. Dye penetrant inspect right and left truss tube assemblies for cracks if chafing or other signs of structural weakening are detected by the visual inspection.

c. Replace any cracked truss tube assembly prior to the next flight.

C) When Beech P/Ns 102-910026-113 and -115 truss tube assemblies which have .072 inch thick walls are installed in the right and left engine nacelles the requirements of this AD no longer apply. Truss tube assemblies used prior to these improved assemblies had .035 inch thick walls.

NOTE: The manufacturer has advised that the P/N 102-910026-113 and -115 truss tube assemblies will not be available until approximately September 1, 1977.

D) The intervals for repetitive inspections set forth in this AD may be adjusted up as much as 10% where required to fit user's maintenance cycles. No adjustment is allowed for the initial "prior to the next flight" inspection.

E) Aircraft may be flown in accordance with FAR 21.197 to a base where this AD can be accomplished, after coordination with the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

F) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

This amendment becomes effective July 1, 1977, to all persons except those to whom it has already been made effective by air mail letter from the FAA dated June 7, 1977.