ENGINE AWARD
During late October 1955, the Air Force notified Reaction Motors that the winning North American entry in the airframe competition was the one that used the XLR30. On 1 December, the New Developments Office of the Fighter Aircraft Division directed the Power Plant Laboratory to prepare a $1,000,000 letter contract with Reaction Motors. However, at the same time the Power Plant Laboratory was further questioning the desirability of the Reaction Motors engine. During preliminary discussions with Reaction Motors, researchers from the NACA expressed concern that anhydrous ammonia would adversely affect the research instrumentation, and again brought up the possibility of converting to a hydrocarbon fuel. The Power Plant Laboratory did not support the change. Even during the initial evaluation the laboratory had not really believed the 2.5-year development estimate, and thought that was at least 6 months short. Changing the propellants would cost at least another year. The laboratory felt that if a 4-year development period was acceptable, the competition should be reopened, since anything over 2.5 years had been penalized during the original evaluation.111
Headquarters proposing to develop the X-15 engine as a continuation of the three years already spent on the XLR30. The admiral believed this arrangement would expedite development, especially since the Navy already had a satisfactory working relationship with Reaction Motors.
The Navy could also make the Reaction Motors test stands at Lake Denmark available to the X-15 program.[22]
On 9 December, Air Force Headquarters forwarded the letter to General Marvin C. Demler, commander of the ARDC. Demler forwarded the Navy request to the Power Plant Laboratory and X-15 Project Office for comment. On 29 December, ARDC Headquarters and the X-15 Project Office held a teletype conference (the predecessor of today’s conference call) to develop arguments against BuAer retaining the engine program. Demler summarized these and forwarded them to Air Force Headquarters on 3 January 1956. The ARDC rejected the Navy position because it felt a single agency should have management responsibility for the entire X-15 program. The Air Force argued that it was already familiar with the XLR30 and was well experienced in the development of man-rated rocket engines, such as the XLR11 (ignoring the fact that it was a derivative of the Navy XLR8). The Air Force also pointed out that it was already using the Reaction Motors at Lake Denmark. These arguments apparently put the matter to rest, since no additional correspondence on the subject seems to exist.[23]
Reaction Motors submitted this technical proposal on 24 January 1956, followed by the cost proposal on 8 February. The company expected to deliver the first engine "within thirty (30) months after we are authorized to proceed." Reaction Motors assigned the new engine the TR- 139 company designation. The Air Force also realized the engine needed a new designation, and on 21 February it formally requested assignment of the XLR99-RM-1 designation. This became official at Wright Field on 6 March and received Navy approval on 29 March. The Reaction Motors cost proposal showed that the entire program would cost $10,480,718 through the delivery of the first flight engine.[24]
During all of this, the NACA was becoming increasingly worried over the seemingly slow progress of the procurement negotiations. On 15 February, the deputy commander for development at the WADC, Brigadier General Victor R. Haugen, wrote to reassure Hugh Dryden that the process was progressing smoothly. Haugen reminded Dryden that one month of delay had been caused by the necessary studies associated with the NACA’s suggestion to change from anhydrous ammonia to a hydrocarbon fuel. Haugen assured Dryden that the procurement agency would issue a letter contract no later than 1 March. As it turned out, his letter was sent the day after the Reaction Motors letter contract had been signed.-125