59-14-01\tBOEING: Applies to the following Boeing 707-100 Series Aircraft Serial Numbers 17586 through 17591, 17609, 17628 through 17637 and 17658 through 17662. \n\tCompliance required as indicated. \n\tAs a result of the complete loss of hydraulic fluid in the utility hydraulic system of a 707- 100 series aircraft caused by the rupture of the aluminum tube assembly in the nose wheel well door-open system, the following modification shall be accomplished. Prior to July 31, 1959, the nose wheel door-open aluminum tube assembly 50-6848-45 shall be replaced with corrosion resistant steel tubing 3/8 inch O.D. by 0.028 inch wall thickness. \n\t(Boeing Service Bulletin No. 412 pertains to this same subject.)