AD 90-23-11 R1 ACTIVE

90-23-11 R1 AIRBUS INDUSTRIE: Amendment 39-6802 as corrected by Amendment 39- 6947. Docket No. 89-NM-202-AD.

Applicability: Model A300 series airplanes, Serial Numbers 001 through 305, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent failure of the ram air turbine to provide hydraulic power in an emergency situation, accomplish the following:

A. For ram air turbines on which neither modification No. RM 370 (Dowty Rotol Service Bulletin 29-76) nor modification No. RM 401 (Dowty Rotol Service Bulletin 29-104) has been accomplished; or on which one, but not both, of those modifications has been accomplished: Perform a ground test of the ram air turbines, in accordance with Dowty Rotol Service Bulletin 29- 124, Revision 3, dated March 29, 1989, as follows:
1. Prior to a. or b., below, whichever occurs later:
a. 4,000 hours time-in-service or 24 months since new or overhaul, whichever occurs first, orb. 600 hours time-in-service or 6 months after the effective date of this AD, whichever occurs first.
2. Repeat the ground test at intervals not to exceed 600 hours time-in-service or 6 months, whichever occurs first.

B. For ram air turbines on which both modification No. RM 370 (Dowty Rotol Service Bulletin 29-76) and modification No. RM 401 (Dowty Rotol Service Bulletin No. 29-104) have been accomplished: Perform a ground test of the ram air turbines, in accordance with Dowty Rotol Service Bulletin 29-124, Revision 3, dated March 29, 1989, as follows:
1. Prior to a. or b., below, whichever occurs later:
a. 7,500 hours time-in-service or 30 months since new or overhaul, whichever occurs first, or
b. 1,500 hours time-in-service or 6 months after the effective date of this AD, whichever occurs first.
2. Repeat the ground test at intervals not to exceed 3,000 hours time-in- service or 12 months, whichever occurs first.

C. If the ram air turbine fails to function properly during the ground tests required by paragraphs A. or B. of this AD, prior to further flight, replace with a serviceable unit, or overhaul the unit, in accordance with Dowty Rotol Overhaul Manual 29-21-14.

D. Prior to 1. or 2., below, whichever occurs later, perform an overhaul of the ram air turbine in accordance with Dowty Rotol Overhaul Manual 29-21-14:
1. 20,000 hours time-in-service or 10 years since new or overhauled, whichever occurs first, or
2. 12 months or 3,000 hours time-in-service after the effective date of the AD, whichever occurs first.

E. Accomplishment of the modifications described in all three Dowty Rotol Service Bulletins 29-125 R1, 29-76, and 29-104, constitutes terminating action for the requirements of this AD.

F. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113.

G. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Airbus Industrie, Airbus Support Division, Avenue Didier Daurat, 31700 Blagnac, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington.

Airworthiness Directive 90-23-11 R1 corrects AD 90-23-11, Amendment 39-6802.

The effective date of the requirements of AD 90-23-11 R1 remains December 17, 1990, as specified in AD 90-23-11.

This amendment (39-6947, AD 90-23-11 R1) is effective on March 22, 1991.