That was just as well, because Agena development had moved very slowly. Agena's two propulsion systems, primary and secondary, were subcontracted to Bell Aerosystems Company in Buffalo, New York. The primary system was built around the Bell Model 8247 engine, into which were pumped storable, hypergolic propellants: unsymmetrical dimethyl hydrazine as fuel, inhibited red fuming nitric acid as oxidizer. Its rated thrust was 71,000 newtons (16,000 pounds), and it helped push Agena into orbit (the main boost coming from the Atlas launch vehicle) as well as powering later orbital changes.
 The major change in the new engine from the standard model on which it was based was in the starting system. Solid-propellant charges, or "starter cans," in the standard model fed high-speed gas to start the turbine which pumped propellants to the engine. Since these cans could not be reused, the number of times the engine could be restarted was limited by the supply of extra starter cans that could be carried. Gemini required an engine that could start at least five times, and Bell proposed to meet this demand by switching to a liquid propellant starting system. Liquids were stored in rechargeable pressurized tanks, which fed them to a gas generator where they were converted to gas and transmitted to the turbine. MSC approved the change in September 1962.66
Like the primary system, the secondary propulsion system was a modification of a system already in use. Several Agenas had carried an auxiliary propulsion system to permit small adjustments of orbits. Two major changes set off the new model, 8250, from the former system: the new secondary propulsion system was modularized instead of having its parts scattered at various sites in the vehicle, and stainless steel bellows were used in place of Teflon bladders to expel propellants from their storage tanks. The Gemini-Agena secondary system comprised two identical modules, separately mounted but fired in unison. Each module was self-contained, with propellants, pressurized nitrogen to operate the bellows, controls, plumbing, and two thrusters. The larger of the two thrusters, rated at 890 newtons (200 pounds), was intended chiefly for minor orbital adjustments, and the smaller 71-newton (16-pound) thruster for orienting the Agena just before the primary propulsion system fired. MSC had approved the modified secondary propulsion system in August 1962.67
Bell had just started its test program when, in the fall of 1962, Gemini's budget crisis struck. While Agena's role in Gemini was under fire, development stopped. But when the smoke lifted, Agena was still very much a part of the program. Contract negotiations between SSD, as NASA's agent, and Lockheed Missiles & Space Company, the prime contractor, began in January 1963.68 Testing of Agena propulsion systems could now begin. When it did, Gemini confronted a major new problem area.
By April 1963, Bell had completed a development version of the primary propulsion system, test-fired it, and shipped it to the Arnold Engineering Development Center (an Air Force test facility in Tullahoma, Tennessee) for a series of tests to prove that the engine would restart at the pressures and temperatures it would meet in Earth orbit. Tests began on 3 May and continued over the next two months with few surprises, although two problems did emerge. One involved the turbine, which tended to spin too fast. The other trouble spot was the  latch-type gas generator valve that controlled the flow of propellants from the start tanks to the gas generator. These valves sometimes opened when they should have stayed closed, failed to open on command, or stuck open. SSD reported to MSC's Atlas/Agena panel that both problems were being closely studied.69
Bad luck rocked the program on 15 July, however, when the two problems combined. The valve failed during a test, calling for an emergency shutdown of the engine. A mistake in the choice of shutdown procedures spun the turbine out of control and destroyed the turbopump assembly. That was the end of testing at Tullahoma. Bell planned to finish the series in its own plant in Buffalo, once the problems had been corrected.
The turbine was fairly easy to fix by adding an electronic circuit to monitor its speed and shut it down automatically if it started spinning too fast.70 But the gas generator valve was not so simply fixed. The failure on 15 July was not its first. A new design was clearly called for. Bell set out to improve its latch-type valve, but how good even an improved version could be was a real question. Bell also went to work on an alternative design, solenoid operated rather than latch-type. Tests over the next few months lent weight to the view that a solenoid valve was not only inherently more reliable but also reduced the complexity of the engine as a whole.71
These advantages, and the still unanswered questions about the latch-type valve, swayed a meeting at the Bell plant on 15 November. The participants decided to switch to solenoid gas generator valves in the Gemini-Agena primary propulsion system and forget about latch-type valves. But development had been much delayed. Preliminary flight-rating tests had been scheduled to begin in September. Switching to the new valves would cost four months and postpone the start of these tests until January 1964.72
Problems and delays also cost money. Negotiations in January and February of 1963 had set the price (including Bell's fee) of primary system development at $4,771,030. The price tag for solving the turbine problem would be about $300,000. Total costs kept going up, especially after the valve design proved hard to resolve. Toward the end of August, the money actually being spent began to exceed that predicted. By late October, Bell's guess at the cost of completing the program had climbed to $6.177 million, which Lockheed thought was at least $300,000 too low.73
Agena's secondary propulsion system developed along the same lines. The new stainless steel bellows produced delays and rising costs. Negotiated cost and fee was $4,395,811; by the time that figure was settled in May, Bell was already asking for an additional $500,000 for the bellows. Scarcely a month later, actual spending was passing predicted  expenses as bellows and tanks required still further design work and more testing. In mid-October, Bell's best estimate for the secondary system was $4.63 million, while Lockheed forecast $5.2 million.74
Growing engine costs were only part of a trend that brought the Gemini-Agena program to another critical pass in the late summer and fall of 1963. Other program costs were also rising, and the comfortable schedule cushion with which Agena had emerged in the revised program of April had eroded. Shortly before NASA Headquarters sanctioned the revised program, Lockheed estimated the cost for its work at roughly $50.4 million, with $17 million needed for fiscal year 1964.75 After meetings in May and June to settle details of the new schedule, Lockheed reported its projected total cost as $53.285 million, but SSD had set its sights even higher. NASA's Air Force agents wanted $37.2 million in fiscal-year 1964 funds for Atlas-Agena, with $26 million of that earmarked for Lockheed's Agena contract. GPO protested. Mathews thought that was too much money in view of the stretched-out schedule and wondered if the program could be completed at any reasonable cost with money being spent at that rate. He warned SSD that such spending could not be allowed.76 When SSD replied on 10 September 1963, current demands were down but the price of the total program was up again, to $57.46 million for Agena and $103.555 million for the entire Atlas-Agena program.77
As costs rose, schedules slipped. One source of delay was attempted improvements. The first Agena D programmed for Gemini was AD-13. Meanwhile, however, the Air Force had started a program to improve the standard Agena, the first of which was to be the AD-62 model. The improved version, unlike the earlier model, came equipped with Bell's 8247 engine, which Gemini needed anyway. Since there seemed plenty of time, Lockheed's contract was amended to replace AD-13 with AD-62 as the first Agena for Gemini, at a cost of two months. Another month or more vanished when the Air Force decided to put the restartable Bell engine in AD-71, rather than AD-62, and GPO agreed to take that one. Work on test facilities at Lockheed was slower than expected, adding to the slippage, and development problems in the propulsion systems threatened to delay the program still further.78
The Gemini Project Office was less than happy with the course of events, its manager least of all. Mathews was concerned about rising costs, of course, but he was just as concerned with the dearth of information that was reaching him through the filter of SSD. With the Air Force running the Gemini-Agena development program for NASA, Mathews could only plead with his agent to exert more control. Not only was GPO being bypassed in the process that approved changes Lockheed wanted to make, but the project office was not always even told what these changes were. Mathews observed, with good reason,  that such decisions as switching from AD-13 to AD-62 (and later AD-71) for the first Gemini-Agena were bound to cause program delays. He urged SSD to think twice about any further changes "considering the deleterious effects that improvements can have."79
SSD, however, was not really much better informed than GPO about Lockheed's changes. Mathews' protests about the lax and shallow control SSD imposed on Lockheed highlighted the gulf that divided NASA from the Air Force on the administration of government contracts. The Air Force preferred to accept Lockheed's record in filling past contracts as proof of its competence. The government was, in essence, paying for Lockheed's expertise. Pressing for too many details of funding technology might hinder progress, cutting into the contractor's flexibility without adding much to its prospects for doing the work. To the Air Force, NASA's demands for detailed technical and financial data seemed at best superfluous, at worst harmful. What NASA wanted, of course, was real control of the program, and that demanded precise and thorough information. Lockheed was merely a case in point. The conflict between NASA and the Air Force over how tight a rein the government needed to exercise spanned the whole range of contract management. For NASA, it was a basic and never-ending problem.80
In an effort to bring the Gemini-Agena program into line, Mathews dusted off and sent to Charles Wurster, SSD's chief of Gemini-Agena engineering, a formal statement of work that dated back to July 1963. Such a document was needed, in any case, since there had been no formal work statement since Marshall Space Flight Center had left the picture. The new statement diverged most sharply from the old in the stress it laid on schedules and management. GPO insisted on tight control of all contractors, chiefly by using the system of coordination panels to keep close watch on what was going on. GPO also wanted the last word on any changes, with none to be approved until that office was satisfied that it had every piece of relevant data. So widely did NASA and Air Force viewpoints diverge that it was 18 months and 15 versions of the work statement later, in March 1965, before MSC and SSD finally agreed.81
NASA also planned to bring the Aerospace Corporation into the target vehicle program in a role analogous to that it already held in the launch vehicle program, general systems engineering and technical direction. The official end of Mercury in June 1963 had freed a number of experienced engineers for other work. Wurster suggested, and Mathews agreed, that Aerospace had something to contribute to Gemini Atlas-Agena program, especially in view of the work it had done with Mercury's Atlas launch vehicle. Also in favor of the plan was a chance to impose a degree of technical continuity via Aerospace across all phases of Gemini being carried out under Air Force contracts.82
 Even if these measures worked, however, they would take time to show any effect. In the meantime, the Gemini Atlas-Agena program was in trouble, with engine development lagging badly, funding and schedules still changing for the worse without much warning. By the end of 1963, most of the time that had seemed so ample in the aftermath of the revised Gemini flight program just eight months before had vanished. The schedule for completing Agena development and for building the first target vehicle now had no slack, and any further problems threatened to delay the first rendezvous launch.83
65 "Official NASA Flight Schedule," NASA Office of Management Reports, approved by Seamans and Hugh L. Dryden, 20 March 1962, pp. 6, 7; memo, Seamans and McMillan for record, "Acceptance of the Joint NASA DOD Ad Hoc Study Group Final Report on Air Force Participation in Gemini, Dated May 6, 1963," 5 Aug. 1963, enclosure 1, "Gemini Launches Master Schedule," as of 2 May 1963.
66 Consolidated Activity Report, May 1962, Tab 18, p. 11; "Gemini Agena Target Vehicle Propulsion Systems Presentation, 2 August 1962," LMSC-A057703, n.d.; "Abstract of Meeting on Atlas/ Agena, August 16, 1962," 22 Aug. 1962; Quarterly Status Report No. 2, for period ending 31 Aug. 1962, p. 25; "Medium Space Vehicles Programs Monthly Progress Report, August 1962," LMSC-447186-26, 20 Sept. 1962, pp. 9-10; Quarterly Status Report No. 3, p. 31; letter, Harold T. Luskin to Maj. Charles A. Wurster, "Contract 04(695)-129, Gemini Program BAC subcontract Financial Status," LMSC/A602008, 11 Nov. 1963, enclosure A, "Model 8247 Development Program: Description of Changes and Increased Effort," pp.1-2; Gemini Agena Target Press Handbook, published by Lockheed Missiles & Space Co. for issuance to news media, LMSC/ A766871, 15 Feb. 1966, pp. 1-11, -12, 4-17 to 4-22.
67 "Abstract of Meeting on Atlas/Agena, August 2, 1962," 14 Aug.1962; Weekly Activity Report, 5-11 Aug.1962, p. 2; TWX, Chamberlin to Friedrich Duerr, GPO 50145, 10 Aug. 1962; memo, James A. Ferrando to Chief, FOD, "Information gathered at the Atlas/Agena coordination meeting held on August 16, 1962," 17 Aug.1962; "Monthly Progress Report, August 1962," pp. 9-10; "GATV Propulsion Systems Presentation"; Quarterly Status Report No. 2, p. 25; Luskin letter, LMSC/A602008, 11 Nov. 1963, enclosure B, "Model 8250 Development Program: Description of Changes and Increased Effort," pp. 1-2; Gemini Agena Target Press Handbook, pp. 1-13,-14, 4-17,-22 to-24.
68 Richard J. Crane, "Gemini Atlas-Agena Program Status Report," 5 Jan. 1963; memo, Crane for record, "Negotiations - Agena Contract between SSD and Lockheed at Los Angeles-Atlas/Agena Program (Jan. 21-25, 1963)," 12 Feb.1963; "Monthly Progress Report, February 1963," LMSC-447186- 32, 20 March 1963, pp. 9-10; Amendment No. 7 to Letter Contract AF 04(695)-129, 18 March 1963, with enclosure, Exhibit C, "Statement of Work, Phase II, Target Vehicle System, Gemini Program"; Negotiated Contract AF 04(695)-129, 22 April 1963, with enclosure, "Exhibit B to Contract AF 04(695)- 129: Statement of Work, Target Vehicle System Development, Gemini Program: Phase I."
69 "Monthly Progress Report, April 1963," LMSC-447186-34, 20 May 1963, pp. 2-1, -5, -6; Quarterly Status Report No, 5, p. 33; "Monthly Progress Report, May 1963," LMSC-447186-35, 20 June 1963, pp. 2-1, -2, -11; "Abstract of Meeting on Atlas/Agena, July 2, 1963," 8 July 1963; Luskin letter, LMSC/A602008, enclosure A, pp. 8-9; TWX, Mathews to SSD, Attn: Wurster, GPO-51054, 11 July 1963.
70 Quarterly Status Report No. 6, p. 73; "Monthly Progress Report, August 1963," LMSC-447186-38, 20 Sept.1963, p.2-1; Luskin letter, LMSC/A602008, 11 Nov. 1963, enclosure A, p. 5; Gemini Agena Target Press Handbook, pp. 4-21, -22.
71 Quarterly Status Report No. 6, p. 73; "Monthly Progress Report, August 1963," p. 2-1; Quarterly Status Report No.7, p. 69; Consolidated Activity Report, 17 Nov. - 21 Dec. 1963, p. 21; TWXs, Mathews to SSD, Attn: Wurster, GPO-52012-LV, 30 July, and GPO-52000-LV, 2 Aug. 1963.
72 Quarterly Status Report No. 7, p. 69; Luskin letter, LMSC/A602008, 11 Nov. 1963, enclosure A, pp. 8-9; TWX, SSD to Mathews, SSVA 21-11-35, 21 Nov. 1963.
73 Luskin letter, LMSC/A602008, 11 Nov. 1963.
75 Memo, V. F. Peterson to L. Orinovsky, "Letter Contract AF 04(695)-129 Reschedule ROM [rough order of magnitude] Funding Requirements," LMSC/A374952, 17 April 1963.
76 Quarterly Status Report No. 5, p. 43, Fig. 1; letter, Herbert J. Ballard to dist., "Gemini Target Management Review - Minutes of Second Meeting," IDC 91-60/208, 24 May 1963; "Abstract of Meeting on Atlas/Agena, June 6 and 7, 1963," 12 June 1963; letter, Peterson to Mathews, "Quarterly Contractor Financial Management Report - NASA 533 Dated June 30, 1963, L/C AF 04(695)-l29," LMSC/A376437, 18 July 1963, with enclosure, "NASA Contractor Financial Management Report" for quarter ending 30 June 1963; TWX, SSD to Mathews, "FY-64 Funding Requirements for Gemini Agena," SSVR 20-6-100, 21 June 1963; TWX, Mathews to SSD, Attn: Wursters [sic], GPO-51082, 5 July 1963; TWX, Mathews to SSD, Attn: Wurster, GPO-54018-A, 24 July 1963.
77 TWX, Mathews to SSD, Attn: Wurster, GPO-541 14-A, 27 Aug. 1963; TWX, Mathews to SSD, Attn: Wurster, GPO-541 12-A, 3 Sept. 1963; letter, Wurster to MSC, Attn: Mathews, "Gemini Agena Program Cost Estimate," 10 Sept. 1963, with enclosures, (1) "Gemini Agena Program Cost Estimate - Summary," as of 6 Sept. 1963, (2) "Gemini Agena Program Cost Estimate - Detail," as of 6 Sept- 1963, and (3) memo, Lt. Col. L. D. Parsons, Jr., to Wurster, "Revised Cost Estimate for Gemini Target," 10 Sept. 1963, with enclosures; letter, Peterson to H. F. Becker, "Quarterly Financial Management Report (NASA Form 533) Dated 29 September,1963, Contract AF 04(695)-129, Gemini," 18 Oct.1963, with enclosure, "NASA Contractor Financial Management Report" for period ending 29 Sept. 1963.
78 Quarterly Status Report No. 6, p. 73; "Monthly Progress Report, September 1963," LMSC-447 186-39, 20 Oct.1963, p. 2-5; Amendment No. 11 to Letter Contract AF 04(695)-129, 23 July 1963; "Monthly Progress Report, October 1963," LMSC-447186-40, 20 Nov. 1963, p. 3-1; "Abstract of Meeting on Atlas-Agena, November 6-7, 1963," 12 Nov. 1963; "Monthly Progress Report, January 1964," LMSC-447 186-43, 20 Feb. 1964, p. 3-1; Purser, "Management Panel Meeting, February 7, 1964,"p. 8; Consolidated Activity Report, 16 Feb. - 21 March 1964, p. 21.
79 Letter, Mathews to Luskin, GPO-03069-A, 12 Sept. 1963; memo, Mathews to dist., "Procedure for Obtaining Information and Support from Lockheed Missiles and Space Company," GPO-03066-A, 12 Sept. 1963; letters, Mathews to Wurster, GPO-02076-LV, 25 Oct. 1963, and GPO-02077-LV, 25 Oct. 1963, with enclosure, "Financial Status of Gemini-Agena Propulsion System Efforts"; letter, Mathews to Wurster, GPO-02081-LV, 7 Nov.
80 Letter, Wurster to Ballard, "Gemini/Agena BAC Subcontract Financial Status," 30 Oct. 1963; letter, Wurster to Mathews, "Schedule Controls for Gemini Agena," 18 Nov. 1963; memo, Schneider to Mathews, "Agena Phase II Contract Negotiations," 6 Jan. 1964; memo, Armstrong to George F. MacDougall, Jr., "Financial Data on GLV Program," APCMT 87-4866, 18 Nov.1963; memo, Armstrong to MacDougall, "Financial & Management Data from SSD concerning Booster Program," APCMT 81-4961, 9 Dec. 1963; letter, Mathews to Lt. Col. Mark E. Rivers, GV02294, 29 July 1964.
81 Letter, Mathews to Wurster, GPO-02012-LV, 15 Nov. 1963, with enclosure, "Statement of Work for Atlas-Agena Target Vehicles to Be Used in Project Gemini," 8 July 1963; cf. letter, Gilruth to Marshall, Attn: Wernher von Braun, "Procurement of Atlas-Agena Space Vehicles," 31 Jan.1962, with enclosures, esp. "Exhibit B: Statement of Work for Atlas-Agena Rendezvous Vehicles to Be Used in Project Gemini," n.d.; William A. Summerfelt, interview, Washington, 24 Jan. 1967; Meyer interview; "Gemini Atlas Agena Target Vehicle System, Management and Responsibilities Agreement between the NASA MSC and the USAF-AFSC-SSD," March 1965, signed by Funk on 31 March, by Col. John B. Hudson on 29 March, and by Gilruth and Mathews on 9 April 1965; Maj. Arminta Harness, interview, Los Angeles, 18 April 1966.
82 Letter, Mathews to Wurster, GPO-02055-LV, 7 Oct. 1963; letter, Gilruth to Brig. Gen. Joseph J. Cody, Jr., GPO-01099-M, 23 Dec. 1963; Bernhard A. Hohmann and Ernst R. Letsch, interviews, El Segundo, Calif., 19 April 1966.
83 "Abstract of Atlas/Agena Meeting, June 6 and 7, 1963"; Weekly Activity Report, 2-8 June 1963, p. 3; "Monthly Progress Report, January 1963," LMSC-447186-31, 20 Feb. 1963, p. 23; TWX, Mathews to SSD, Attn: Maj. John G. Albert, GPO-51012, 13 June 1963; TWX, Mathews to SSD, Attn: Wurster, GPO-51057, 9 July 1963; "Monthly Progress Report, November 1963," LMSC-447186-41, 20 Dec. 1963, pp. 5-9.