According to the plan, ABMA was still dissatisfied with the engine arrangements. It was pointed out that all work was proceeding on known and proven  designs, whereas they felt that some engineering efforts should be devoted to development of higher-thrust engines. ABM also mentioned that it  planned to investigate different fuels, oxidizers, and additives that might afford greater efficiency and reduce logistic problems. Basically, it was requested  that an additional contractor be phased into the engine program 36 . OSD-BMC reviewed the plan, and took several actions. For example, they disapproved the introduction of a new engine contractor; however, it was noted  there were modifications that could be made to the NAA and Aerojet engines to improve performance. Moreover, the idea of forward research was not  shelved, as DOD had directed its R&D element to make a study on future requirements for higher-thrust engines, and ABMA was told to proceed with its  liquid propellant research studies. On another important matter--the radio inertial guidance system backup program OSD- BMC noted that such  development was contingent on construction of an engineering facility at JPL. Funds were approved for buying contractor equipment and training  equipment, but FY 1957 MCA construction fund approval was deferred pending a complete review. In all cases, ABMA was cautioned to maintain close  coordination with the Air Force so as to assure joint development of items common to the IRBMs 37 . ______________________________

36. ABMA Plan for IRBM 2 Msl Dev FY 56-57, 23 Feb 56, Hist Off files. 37. Memo, OSD-BMC to JANBMC, 25 May 56, subj: JUP Fiscal & Dev Plans for FY 1956 & FY 1957; in ABM Ref Book, subj: JUP, Part I, Tab C.