Adhering to the long established practice under the NACA, it became NASA policy to look to the Military to furnish the aircraft needed to carry on the in-flight research programs and in some cases full- scale wind-tunnel tests, necessary in pursuing NASA's assigned objective of preserving the role of the United States as a leader in aeronautical sciences and technology. In addition to the need to conduct flight research programs to validate theoretical studies and laboratory empirical data, NASA had a continuing need to operate aircraft in various program support activities; i. e., drop testing of spacecraft and sub-systems, calibration of tracking networks, training of tracking station personnel, chase aircraft, aerial photography, recovery operations, range surveillance, astronaut training, maintenance of astronaut readiness, special purpose cargo airlift, and administrative transportation. Except to meet the last requirement, for which NASA rented or purchased and operated a limited number of small transport types, NASA depended primarily upon the availability of suitable aircraft on loan from the Military Services.
DDR&E and the Military Services were fully- cooperative in meeting NASA needs involving the loan of aircraft. Except in a very few cases wherein operational requirements of the DOD had to take precedence, the aircraft requested by NASA were provided. In those cases - for example, the F-111 - in which the assistance of NASA was requested in conducting full-scale wind-tunnel tests or in-flight studies of a military aircraft, the test aircraft was made available along with the request for NASA support.
The loan of an aircraft was usually covered by a formal agreement document. Some flight research programs, such as the X-15 and XB-70 programs and the lifting-body programs, were jointly conducted and supported, but in most cases NASA funded the maintenance and alteration costs of' air-craft on loan to NASA. As a rule, the principle of mutual interest was applied to determine the extent to which the support rendered by a Military Service to a NASA program using a lent aircraft was reimbursable. In a general sense, the Services had an interest in all NASA aeronautical R&D programs aimed at advancing the state-of-the art in aeronautical technology.
Program offices and Centers requiring the use of an aircraft type the DOD inventory made known their needs to Defense Affairs, and we usually made the initial approach to determine whether the type required could be made available. If so, Defense Affairs negotiated the terms of the loan worked with the DOD agency involved to draft a covering agreement, in the process of which we received functional support from other Headquarters offices such as the General Counsel. Some thirty such agreements or revisions of agreements were negotiated by Defense Affairs during the period of this narrative. These aircraft loan agreements and joint flight research project  agreements usually covered such matters as purpose and objectives of the project; management, technical, operational, and logistic support responsibility; source and description of basic equipment; provision of spares; funding arrangement; duration of the .agreement; accident investigation; liability for third party claims; financial responsibility for damage to or total loss of equipment on loan; the processing and dissemination of data; public relations; security; reports and records; and the condition of lent equipment upon ultimate return.
In late 1964, Defense Affairs negotiated a NASA-USAF Memorandum of Understanding, retroactively effective on July 1, 1964, which consolidated earlier agreements covering five T-38A and nine T-33A aircraft which had on various previous dates been lent by the Air Force to NASA for use in support of astronaut space flight readiness training and which were then in place at Ellington Air Force Base, Houston, Texas. This general agreement was designed to cover, with the negotiation of brief addenda, any additional aircraft which might be lent by the Air Force for this purpose after that date. The agreement made provision for the Air Force to train NASA and contract maintenance personnel in the operation and maintenance of these planes. All USAF support was to be reimbursable. (Later, title to the T-33A and T-38A trainers at MSC was transferred to NASA, and NASA purchased twenty-one T-38A's through the Air Force for astronaut training. By agreement five of the twenty-one were retained by the Air Force as payback for the five T-38A's transferred to NASA.)
Attached are summary tabulations which list the aircraft on loan to NASA from the Military Services during the years 1963 through 1967, with brief notations as to the location and use being made of each aircraft.
 NASA-DOD Agreement Concerning the F12/SR71 Aircraft
During mid-1967, Defense Affairs assisted Mr. Charles W. Harper, Deputy Associate Administrator for Advanced Research and Technology (Aeronautics), in lengthy negotiations to obtain release from the Air Force of certain technical data on the F12/SR71 aircraft series needed by NASA to fulfill effectively its research role in aeronautics and its supporting role in the development, under government programs, of both military and civilian supersonic aircraft. DOD and the Air Force concurred in the desirability of making the cats available to NASA, but difficulty was encountered in persuading the manufacturer to release the data, which were being held closely as proprietary information. NASA had formulated plans for studies of the F12/SR71 aircraft with the objectives of (1) helping to establish correlation between flight and propulsion system performance and predictions based upon ground facility tests and analog simulation, (2) assessing the technology advances as represented by these aircraft. and (3) identifying problem areas that had not been anticipated in early studies of other supersonic aircraft development programs.
Detailed arrangements for the collection and processing of the data needed by NASA were finally worked out and agreed upon by Col. P. N. Ellis, USAF, the F12/SR71 Systems Program Director, and Mr. J. Lloyd Jones, Jr., NASA Program Manager, Ames Research Center. These were incorporated in a "NASA-DOD Memorandum of Understanding - Collection of F-12/SR71 Aircraft Technical Data," signed by Mr. Harper for NASA and Dr. A. H. Flax for the DOD, effective October 4, 1967.
 NASA. Analysis of Aircraft on Loan from Military Services as of December 31, 1963.
[235-236] NASA. Analysis of Aircraft on Loan from Military Services as of December 31, 1964. Fiscal Year 1966 Budget Estimates.
[237-238] NASA. Analysis of Aircraft on Loan from Military Services as of June 30, 1965. Fiscal Year 1967 Budget Estimates.
[239-240] NASA. Analysis of Aircraft on Loan from Military Services as of June 30, 1966. Fiscal Year 1968 Budget Estimates.
[241-242] NASA. Analysis of Aircraft on Loan from Military Services as of June 30, 1967. Fiscal Year 1969 Budget Estimates.