61-24-02: Hydraulic System Modifications

61-24-02 DOUGLAS: Amdt. 370 Part 507 Federal Register November 23, 1961. Applies to All DC-8 Aircraft, Serial Nos. 45252-45289, 45291-45306, 45376-45393, 45408-45413, 45416-45419, 45421-45431, 45433-45437, 45442-45445, 45526, 45565-45570, 45588-45606, 45609-45614, 45616-45628, 45636. \n\n\tCompliance required within 1,000 hours' time in service after November 23, 1961, but in no event later than February 28, 1962, except as provided in paragraph (e). \n\n\tAs a result of numerous recent incidents associated with hydraulic system failures or malfunctions, the aircraft shall be modified to incorporate the following: \n\n\t(a) A dual source of hydraulic power for the actuation of all wing spoilers during landing roll, in accordance with Douglas DC-8 Service Bulletin 29-39 or FAA approved equivalent. \n\n\t(b) Increased brake accumulator capacity, in accordance with Douglas DC-8 Service Bulletin 29-41 or FAA approved equivalent. \n\n\t(c) A dual source of hydraulic power for the rudderpower system, in accordance with Douglas DC-8 Service Bulletin 27-117 or FAA approved equivalent. \n\n\t(d) A source of power to actuate the nose wheel steering system when the airplane hydraulic system is being operated with the hydraulic system selector handle in the "main gear down lock and flaps" position, and additional hydraulic fluid reserve capacity and related changes in the fluid reservoir quantity indicating system, in accordance with Douglas DC-8 Service Bulletin 32-73 or FAA approved equivalent. \n\n\t(e) To reduce to acceptable levels the hydraulic system pressure fluctuations induced by the auxiliary hydraulic pump: \n\n\t\t(1) By no later than February 28, 1962, bypass the surge damper which may have been installed in accordance with Douglas DC-8 Service Bulletin 29-35. The bypass method shall be in accordance with steps 1 through 6 of Addendum Number 1 to Service Bulletin 29-35 dated February 16, 1962. \n\n\t\t(2) As soon as necessary parts are available but in no eventlater than April 30, 1962, install surge damper in accordance with Douglas Service Bulletin 29-35, Reissue Number 1 dated November 8, 1961, as amended by Addendum Number 1 of Service Bulletin 29-35 dated February 16, 1962. \n\n\t(f) Dampers to reduce to an acceptable level the surge pressure induced in the hydraulic system when the aileron and rudder power systems are activated, in accordance with Douglas DC-8 Service Bulletin 27-109, revision No. 1 to reissue No. 1 dated November 15, 1961, or later FAA approved version. \n\n\t(g) The FAA approval of the equivalent methods of compliance with the modifications required by paragraphs (a) through (d) shall be obtained through the Chief, Engineering and Manufacturing Branch, FAA Western Region. \n\n\tThis directive effective November 23, 1961. \n\n\tRevised March 14, 1962, for all persons except those to whom it was made effective immediately by telegram dated February 21, 1962.