Chariots for Apollo: A History of Manned Lunar Spacecraft|
The "Sub-Prime" and the Radar Problem
Grumman contracted with Aerospace Communications and Controls Division of Radio Corporation of America (RCA) in Burlington, Massachusetts, for engineering support, radars, an inflight test system, and components of the stabilization and control system. RCA, the "sub-prime" contractor, was also to design and manufacture ground checkout equipment for these items. Although the two companies had worked together for years, the Grumman-RCA experience with the lunar module was fraught with difficulties. Electronics components became a pacing item in the development of the lander's subsystems, causing unhappiness at NASA Headquarters and culminating in an investigation by the General Accounting Office.31
The extremely complex stabilization and control system was the source of much of the trouble. Design had to await definition of mission requirements and planning. To complicate matters further, Grumman did not buy the total system but merely procured parts, through RCA, from Minneapolis-Honeywell, which supplied similar items to North American for the command module. There was some commonality of parts, but the lander hardware had to be repackaged, often causing lengthy delays. Communications gear was purchased from Collins Radio and Motorola in the same manner. Tiring of this roundabout way of doing business, Houston finally decided to speed things up by supplying the television camera, originally intended for development by RCA, as government-furnished equipment. In mid-1964, the Westinghouse Electric Company was asked to submit a bid for the camera.32
RCA's role was further cut when inflight maintenance was canceled. At the outset of the program, the crews had been expected to perform basic repairs to electronics equipment in the lander, as well as in the command module, using spare parts stowed aboard the spacecraft. By mid-1963, Houston Flight Operations Director Christopher Kraft was arguing that the crewmen simply would not have time to repair faulty hardware during lunar module operations. Thomas Kelly was convinced that inflight maintenance would degrade reliability instead of improving it. This was probably true, since the electronic spares would be subjected to cabin humidity even when stowed. When George Mueller took over as manned space flight chief in Washington, he also had reservations about the plan. Inflight maintenance was deleted from the program and the crew was to rely on operational displays and the caution and warning system to detect malfunctions. Redundancy would be "wired in," with duplicate or backup components the crew could switch to, and all electronics inside the cabin would be hermetically sealed to protect against moisture and contaminants.33
Radar, tied into the guidance and navigation system, was one of the hardest pieces of the lunar module to qualify. Two sets would be used, one for landing, the other for rendezvous. Under its blanket subcontract for electronics, RCA was to design the system, manufacture the rendezvous radar, and buy the landing subsystem. After evaluating proposals from four bidders, RCA picked Ryan Aeronautical Company, developer of landing radar for Surveyor.34
Development of the lunar module radar was not expected to be difficult, since no technological breakthrough was demanded for either system. Integrating these sets with the guidance and navigation system, however, was another matter. There were also problems in properly placing and insulating the antennas. Getting the precise ranging accuracy needed and overcoming the weight increases that resulted from meeting these requirements probably posed the biggest problem of all. A happy medium between optimum weight and desired reliability was elusive, and progress was practically nil.
During the final quarter of 1964, the chief of guidance and control in Houston warned Shea that the radar program was having trouble with weight, accuracy, reliability, thermal characteristics, and costs. Shea and William A. Lee, chief of MSC's Apollo Operations Planning Division, began to think about omitting the rendezvous radar from both the command and lunar modules. Lee believed these units were doubly redundant, since rendezvous could be performed by the command module pilot with the aid of data relayed by the Manned Space Flight Network. Donald G. Wiseman, an instrumentation and electronics specialist in Houston, thought rendezvous could also be conducted by the lunar module crew, using ground, optical tracking, and S-band and VHF communications equipment ranging information in place of radar. Although not everyone agreed that the system should be eliminated, work was started on the development of an optical tracker.35
31. Lang TWX to NASA Hq., Attn.: Brackett, 13 June 1962; MSC news release 63-143, 28 Aug. 1963; Holmes to Dir., Proc. and Supply Div., "Selection of RCA for LEM Electronic Subsystems Procurement," 21 June 1963; Frederick A. Zito to Gaylor, "Utilization of RCA Engineering Assistance on the LEM Program; Comments on," 2 April 1963; Rector to Decker, "Review of GAEC Proposed Utilization of RCA Engineering Assistance on LEM Program," 16 April 1963, with enc.; Donald G. Wiseman to Dep. Chief, Instrumentation and Electronic Syst. Div. (IESD), "Trip to GAEC," 18 March 1964; Zito to Gaylor and Small, "Termination of RCA Engineering Assistance on the LEM Program, . . . Comments on," 27 July 1964; Porter H. Gilbert and Henry W. Flagg, Jr., interview, Houston, 8 April 1970; Comptroller General, "Review of Procurement of Lunar Module Radars," report to Congress, B-158390, 17 April 1968.
32. Minneapolis-Honeywell, "Apollo Stabilization and Control by Honeywell," brochure, ADC 330 5/15, July 1969; Gene T. Rice to Rector, "C/M and LEM stabilization and control system interface," 27 Aug. 1962; Project Apollo Quarterly Status Report no. 5, for period ending 30 Sept. 1963, pp. 28-29; Lang TWX to NASA Hq., Attn.: George J. Vecchietti and Daniel A. Linn, 17 March 1964; Ralph S. Sawyer to Mgr., ASPO, "LEM/CSM Communication Subsystem Commonality," 22 Dec. 1964; Clinton Taylor and Rector TWX to North American and Grumman, Attn.: Cozad and Mullaney, 10 Nov. 1964; Decker to Actg. Mgr., ASPO, "TV," 24 July 1963; Grumman Report no. 11, p. 18; ASPO Weekly Management Report, 28 May-4 June 1964.
33. Shea TWX to Grumman, Attn.: Mullaney, 25 Oct. 1963; Christopher C. Kraft, Jr., to Mgr., LEM Admin. Off., "Comments on LEM Maintenance Plan, GAEC Report LPL 635-1, dated May 15, 1963," 2 July 1963; David W. Gilbert to Mgr., ASPO, "Implementation of Built-in Redundancy for Spacecraft Sub-systems," 30 Oct. 1963; Henry P. Yschek to North American, contract change authorization no.213, 9 June 1964; Rector to Grumman, Attn.: Mullaney, "Lunar Excursion Module Recommendation Concerning LEM Emergency Detection," 3 June 1964; J. Danaher to LEM Syst. and Subsyst. Eng., "LEM Caution and Warning Subsystem Operating Philosophy," 30 Sept. 1964; Rector to LEM Contr. Off.,"Request for PCCP - Hermetic Sealing of All Electrical Electronic Equipment within LEM Cabin," 13 Nov. 1964, with encs.
34. Piland to Grumman, Attn.: Mullaney, "Minutes of Radar Coordination Meetings," 25 March 1963, with enc., abstract of Meeting No. 2 of Technical Coordination Group on LEM Radar, 5 Feb. 1963, with encs.; Owen S. Olds to MSC, Attn.: Maynard, "Lunar Landing Radar System," 23 April 1963; David Gilbert to Dep. Mgr., ASPO, "LEM Radar," 1 May 1963; J. R. Iverson to MSC, Attn.: Robert E. Lewis, 21 May 1963; Lewis to Dep. Mgr., LEM, "Grumman RCA Make or Buy Recommendation for Rendezvous and Landing Radars," 8 Aug. 1963; Richard F. Broderick, memo for record, "Evaluation of proposals for the LEM Landing Radar," 29 Nov. 1963, with enc.; Lewis to Mgr., ASPO, "Apollo Rendezvous Radar Transponder," 2 Dec. 1963, with enc.; Rector to Grumman, Attn.: Mullaney, "Contractor Responsibilities for Rendezvous Radar Transponder and Landing Radar," 21 April 1964, with encs.; idem, TWX, 11 Dec. 1964; Patrick Rozas and Allen R. Cunningham, "Lunar Module Landing Radar and Rendezvous Radar," AER TN S-311 (MSC-05251), review copy, November 1971.
35. Wayne Young to G&N Contr. Off., "Section 2.1.6 Landing and Rendezvous Radar of the May 22, 1964, revision of the Statement of Work, Navigation and Guidance Systems (CM and LEM) development," 8 June 1964; LEM PO, "Problems," 9-15 July 1964; Aaron Cohen to Chief, Ops. Planning Div. (OPD), "CSM Rendezvous Radar," 15 Oct. 1964; William Lee to Chief, OPD, "Potential deletion of the CSM rendezvous radar," 19 Oct. 1964; Slayton to Chief, OPD, subj. as above, 27 Oct. 1964; Sawyer to Chief, OPD, subj. as above, 17 Nov. 1964; Robert C. Duncan to Chief, OPD, "CSM rendezvous radar," 28 Oct. 1964; Wiseman to Chief, IESD, "Meeting on LEM/CSM rendezvous," 9 Dec. 1964; Wayne Young TWX to MIT, Attn.: Trageser, 10 Dec. 1964.