AD 75-22-05

75-22-05 DETROIT DIESEL ALLISON: Amendment 39-2391. Applies to Detroit Diesel Allison Model 501-D13 series engines which incorporate P/N 6829072 and 6847112 second stage turbine wheels with the serial numbers listed below:

Compliance required as indicated:

I. Remove from service in accordance with the schedule in paragraphs I.A, B, C, and D, wheels with the following serial numbers:

CA-6108

CA-6112

CA-6114

CA-6056

CA-6083

KK-2052 to and including KK-2053 KK-2055 to and including KK-2085 KK-2092 to and including KK-2094 KK-2099 to and including KK-2100 KK-2102 to and including KK-2115 KK-2117 to and including KK-2167 KK-2169 to and including KK-2251 KK-2253 to and including KK-2329 KK-2332 to and including KK-2382 KK-2384 to and including KK-2460 KK-2475 to and including KK-2500 KK-2502 to and including KK-2643 KK-2645 to and including KK-2682 KK-2763 to and including KK-2813 KK-2824 to and including KK-2857 KK-2873 to and including KK-2901 KK-3033 to and including KK-3034 KK-3047 to and including KK-3048 KK-3063 to and including KK-3075 KK-3108 to and including KK-3118 KK-3136 to and including KK-3239 KK-3287 to and including KK-3300 KK-3314 to and including KK-3327 KK-3617 to and including KK-3643 KK-3756 to and including KK-3768 KK-3867 to and including KK-3880 KK-11829 to and including KK-11832 KK-16501 to and including KK-16589 KK-16901 to and including KK-16999 KK-19966 to and including KK-20064

NOTE: At time of overhaul, some wheels have R1, R2, R3, R4, or R5 added as a suffix to the wheel serial number. The suffix should be disregarded in determining the applicability of this A.D.

A. Remove from service within the next 200 cycles, wheels which have 16,000 or more total cycles on the effective date of this A.D.

B. Remove from service within the next 400 cycles, or prior to exceeding 16,200 total cycles, which ever comes first, wheels which have from 14,000 to 16,000 total cycles on the effective date of this A.D.

C. Remove from service within the next 500 cycles, or prior to exceeding 14,400 total cycles whichever comes first, wheels which have 13,500 to 14,000 total cycles on the effective date of this A.D. D. Remove from service prior to exceeding 14,000 total cycles, wheels which have less than 13,500 total cycles on the effective date of this A.D.

II. Remove from service in accordance with the schedule in paragraphs II A, B, C, D, E and F, wheels with the following serial numbers:

KK-3132 and KK-15499

KK-29611 to and including KK-2997 KK-3035 to and including KK-3046 KK-3049 to and including KK-3062 KK-3076 to and including KK-3107 KK-3119 to and including KK-3130 KK-3240 to and including KK-3286 KK-3301 to and including KK-3313 KK-3328 to and including KK-3364 KK-3376 to and includingKK-3580 KK-3582 to and including KK-3616 KK-3644 to and including KK-3755 KK-3769 to and including KK-3782 KK-3798 to and including KK-3866 KK-3881 to and including KK-3949 KK-3963 to and including KK-3976 KK-3996 to and including KK-4006 KK-1180 to and including KK-11821 KK-14201 to and including KK-14207 KK-14466 to and including KK-14470 KK-14801 to and including KK-14815 KK-15704 to and including KK-15784 KK-20577 to and including KK-20680 KK-21599 to and including KK-21653

A. Remove from service within the next 200 cycles, wheels which have 16,000 or more total cycles on the effective date of this A.D.

B. Remove from service within the next 400 cycles, or prior to exceeding 16,200 total cycles, whichever comes first, wheels which have from 14,000 to 16,000 total cycles on the effective date of this A.D.

C. Remove from service within the next 1000 cycles, or prior to exceeding 14,400 total cycles whichever comes first, wheels which have 10,500 to 14,000 total cycles on the effective date of this A.D.

D. Remove from service within the next 2,000 cycles, or prior to exceeding 11,500 total cycles, whichever comes first, wheels which have from 7,000 to 10,500 total cycles on the effective date of this A.D.

E. Remove from service within the next 2,100 cycles, or prior to exceeding 9,000 total cycles, whichever comes first, wheels which have from 4,900 to 7,000 total cycles on the effective date of this A.D.

F. Remove from service prior to exceeding 7,000 total cycles, wheels with less than 4,900 total cycles on the effective date of this A.D.

III. Remove from service in accordance with the schedule in paragraphs III A, and B, wheels with serial numbers not specified in Paragraphs I or II above, or in AD 75-17-32 (Amdt. 39-2336).

A. Remove from service within the next 100 cycles, wheels which have 6900 or more total cycles on the effective date of this A.D.

B. Removefrom service prior to exceeding 7,000 total cycles, wheels which have less than 6,900 total cycles on the effective date of this A.D.

IV. Wheels removed per paragraphs I, II or III above, which have less than 14,000 total cycles may be inspected as specified in IV.A and B, and if found satisfactory, may be returned to service until they reach the total number of cycles specified in IV.C; however, no wheels may exceed 11,000 total hours in service.

A. Inspect for hub spline cracks using fluorescent penetrant method FP-30A or ZL-30A.

B. Inspect and classify microstructure per Detroit Diesel Allison 501-D13 Commercial Overhaul Information Letter No. COIL-349.

C. Wheels inspected and classified per IV.A and B above, may be continued in service as follows:

1. Light carbide and medium light carbide wheels may be operated for a maximum of 14,000 cycles total.

2. Medium heavy carbide wheels may be operated for 7,000 cycles between inspections per IV.A andB above, for a maximum of 14,000 total cycles.

3. Heavy carbide wheels may not be operated more than 7,000 total cycles maximum.

V. For the purposes of this airworthiness directive, a cycle is defined as one takeoff.

VI. Detroit Diesel Allison 501-D13 Commercial Service Letter No. CSL-235 pertains to this subject.

The manufacturer's service letter identified and described in this directive is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received this document from the manufacturer may obtain copies upon request to Detroit Diesel Allison, Division of General Motors Corporation, P. O. Box 894, Indianapolis, Indiana, 46206.

This document may also be examined at the Office of the Regional Counsel, Federal Aviation Administration, Great Lakes Region, 2300 East Devon Avenue, Des Plaines, Illinois, 60018, and at Federal Aviation Administration Headquarters, 800 Independence Avenue, S.W., Washington, D.C., 20591. A historical file on this AD which includes the incorporated material in full is maintained by the Federal Aviation Administration at its headquarters in Washington, D.C., and at the Great Lakes Regional Office in Des Plaines, Illinois.

This supersedes Amendment 39-2117, Airworthiness Directive 75-05-15. This amendment is effective October 23, 1975.