AD 53-25-01

AD Final Rules - DRS_53-25-01.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
53-25-01
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; DOUGLAS DC-6 Series Aircraft
Subject:
Aileron Control System
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
Make:
The Boeing Company
Model:
DC-6 | DC-6A | DC-6B
Product Type:
Aircraft
Product Subtype:
Large Airplane
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 53-25-01
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:  

AD NUMBER:   53-25-01

SUBJECT HEADING:   Airworthiness Directives; DOUGLAS DC-6 Series Aircraft


ACTION:  

SUMMARY:  

DATES:  

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
53-25-01 DOUGLAS: Applies to Model DC-6 Series Aircraft as Indicated Below.

Compliance required as indicated.

There have been several instances wherein cracks have been found in the aileron-cross upper pivot end. In order to preclude the occurrences of additional failures of this part, an inspection should be made as described below. The accomplishment of this directive is for inspection and/or replacement of the upper pivot end of the aileron-cross bellcrack tube located in the center wing fuselage section at Station 479.

1. Inspection (Fuselage Nos. 1 through 434).

Following inspection must be conducted:

(A) On all DC-6A and DC-6B aircraft and on all DC-6 aircraft incorporating the DC-6B type dual flying tab installation, as soon as practicable but not later than the next 50 hours of operation, unless the inspection has already been accomplished.

(B) On all DC-6, -6A and -6B aircraft at each airplane overhaul period or after each 2,000 hours of operation, whichever occurs first and after each time the airplane is exposed to high ground gust conditions. This inspection is to be repeated at each 2,000-hour period until parts are replaced as described below. Using at least an 8-power magnifying glass and/or dye penetrant method or equivalent, make inspection for cracks at the shoulder corner radius of the aileron-cross upper pivot end P/N 4359401, that supports the bellcrank bearing. If cracks are found install new parts as indicated in item 2 before next scheduled flight.

2. Rework (Fuselage Nos. 1 through 434).

If cracks are found in the aileron-cross upper pivot end P/N 4339401, the part should be replaced with a new pivot end assembly P/N 4492248 and a new bellcrank arm assembly P/N 4492247 in accordance with the rework procedures outlined in Douglas Service Letter No. 153 Supplement No. 2 dated December 4, 1953. New parts will be installed in production effective on fuselage No. 435 and subsequent.

3. Preventive Installation (DC-6 Series as Indicated).

To eliminate the tendency for the aileron control tabs to flap during high ground gust conditions, a preloaded centering spring mechanism P/M 3405566 may be installed on DC-6 Series aircraft as listed in Douglas Service Letter No. 159 dated May 28, 1953. A new trim tab mechanism will be installed in production effective on fuselage Nos. 420 and subsequent.

4. Operations Information.

During ground operation in high gust conditions with gust locks on, any tendency for the control wheel to move may be resisted by holding the wheel in neutral. Restraint should not be applied by holding wheel against the stops. The FAA-approved Airplane Operating Manual should be revised to include this information.

(Douglas Service Letter No. 153 dated April 28, 1953, also covers this same subject.)


FOOTER: