Declassified Records

GAMBIT Dual Mode

On 17 September 2011 the NRO declassified the HEXAGON and GAMBIT satellite reconnaissance program. The first release of documents accompanied the formal announcement of the declassification. The second release focused on the HEXAGON program. This third release provides the public with a new collection of documents focused on GAMBIT Dual Mode.

Soon after the first launch of CORONA, the NRO began developing the first high resolution satellite program, codenamed GAMBIT. The system evolved into GAMBIT-3, which was first launched in 1966. With the approaching end of the CORONA program in 1972, the United States' ability to obtain imagery of large swaths of terrain was in danger. The replacement large area system, HEXAGON, began its acquisition phase in 1966. In the late 1960's, fears of possible delays to the HEXAGON program, challenged engineers and policy makers to come up with a potential replacement for CORONA's search capability. On Missions 4352 the NRO experimented with a concept of a slightly modified GAMBIT-3 vehicle which would enter a high altitude (300-350 mile perigee) orbit for the first ninety days, before going back to a more typical orbit with a 78 mile perigee for the remainder of its mission. This project was variously named HIGHERBOY, HIGHBOY, or Dual Mode. The NRO personnel and industry partners accepted the challenge from policymakers and worked within tight budget constraints since resources were already earmarked for two large systems. Ultimately, GAMBIT Dual Mode demonstrated the ability of the NRO and the Intelligence Community to develop a creative approach to resolve a critical intelligence collection problem. Dual Mode operations were successful, and the space vehicle functioned through the entire mission. This effort would have been hailed as an innovative success if it were not for the malfunctions that occurred with the film buckets and resultant loss or degradation of photoreconnaissance imagery.

Index, Declassified Documents

# Document Title Date No. of Pages
1 GAMBIT HIGHERBOY broached at SAFSP Program Review 9/23/1971 4
Memo to Col. Bradburn with a question regarding how many HIGHERBOYs to fly, if any, in 1972. Decision on the matter can be seen in the marginalia. The memo also includes a listing of action items that resulted from a 10 September 1971 SAFSP program review meeting.
2 Project HIGHBOY Support 10/30/1972 1
Cable requesting Program A support for Project HIGHBOY.
3 GAMBIT HIGHERBOY Capability 12/7/1972 2
Memo to Dr. McLucas with a request for action. The memo asks "Should the GAMBIT HIGHERBOY capability be retained after Vehicle 41?"
4 GAMBIT Dual Mode - An Image Collection System for the 1980s Apr-77 73
Report showcasing the possibilities of GAMBIT Dual Mode. Prepared for SAFSP by Eastman Kodak and Lockheed Missiles and Space Company.
5 Dual Mode GAMBIT May-77 2
Cable about reducing the call-up time of the GAMBIT Dual Mode Vehicle. The limiting factors to readiness are listed.
6 Gap in Search Requirements Satisfaction Jun-77 1
Cable discussing efforts to plug a gap in search requirement satisfaction. General Kulpa explains his investigation for an alternative to GAMBIT Dual Mode.
7 Dual Mode GAMBIT Jun-77 4
Cable discussing four reduced call-up alternatives for GAMBIT Dual Mode.
8 GAMBIT Program Jun-77 4
Cable with action required, indicating that DNRO Mark requested the budget figures for a Dual Mode to serve as a back-up reconnaissance system in case GAMBIT is cancelled.
9 GAMBIT Program Sep-77 3
Cable responding to request for information on the Dual Mode GAMBIT alternatives. First indication of Vehicle 52 to serve as a demonstration of the capability of both high resolution and search mode.
10 GAMBIT Backup with two Dual Mode Vehicles Nov-77 2
Cable discussion of an approach to convert two GAMBIT vehicles into Dual Mode. Discussion of which vehicles to convert and which to avoid retrofitting.
11 Data Track Requirements for Dual Mode GAMBIT Apr-78 1
Cable discussing the community's response to a call for information on requirements. The cable also includes a discussion of the ExSubCom meeting that took place 6 April 1978.
12 GAMBIT Dual Mode Search Surveillance 1978 55
A Dual Mode orbital planning document prepared by the Program office. This document provides the capabilities of the hardware and the orbital options available. (Note: This document is in color)
13 GAMBIT Dual Mode Feb-79 3
Cable discussing the maximum altitude for Dual Mode GAMBIT, the strategies for estimating GAMBIT Dual Mode's performance against the search requirements, and simulation results.
14 Dual Mode GAMBIT Simulation - Scale Study 7/1/1979 160
A scale study analysis for GAMBIT Dual Mode that investigates the rate of change of quality with scale for different film types.
15 GAMBIT Dual Mode Demonstration Sept-79 1
Cable pointing out the question: "How necessary is the Dual Mode demonstration in 1980 when weighed against the 25% reduction in GAMBIT resources?" and recommending SAFSP proactive response to the intelligence community.
16 GAMBIT Dual Mode Extended Altitude Reconnaissance System 12/14/1979 84
Briefing slides about the new GAMBIT Dual Mode configuration. (Note: This document is in color)
17 GAMBIT Dual Mode Study Summary 1979 1
A one page summary about Dual Mode GAMBIT capabilities.
18 Dual Mode Document Review Feb-80 2
Cable providing notes to a draft document. Discussion of GAMBIT Dual Mode 65NM perigee capability, changes to the Dual Mode vehicle availability, and NIIRS capability at search altitude.
19 Contingency Mission Support Data Apr-80 1
Cable from COMIREX asking for information on contingency GAMBIT mission options which include GAMBIT Dual Mode.
20 Dual Mode GAMBIT Simulations May-80 1
Cable indicating forthcoming COMIREX/ICRS guidance and tasking for GAMBIT Dual Mode. Also, reference is made to a GAMBIT NIIRS Model which would not be included in the simulation.
21 Dual Mode Software Transition May-80 2
Cable providing a status update on a software transition for GAMBIT Dual Mode.
22 Dual Mode GAMBIT Performance 5/7/1980 1
Memo to DDCI for Tasking Collection, providing a confirmation of estimates of GAMBIT Dual Mode's coverage.
23 Recommended Uses for the Five Inch GAMBIT Camera Jul-80 2
Cable listing the various uses of the five inch camera at low and high altitudes. Other options to satisfy the coverage requirements are listed as well.
24 Assessments of GAMBIT and HEXAGON Performance JUl-80 1
Cable requesting information from Program A about Quality-Quantity tradeoffs for launches of the remaining GAMBIT and HEXAGON vehicles after 1980.
25 GAMBIT Launch Options Jul-80 1
Cable requesting recommendations for satisfying economic (agricultural) and drug intelligence needs using Vehicles 4351 and 4352.
26 GAMBIT Flyout Strategy 7/7/1980 1
Differing opinion with regard to GAMBIT Dual Mode flyout strategy. Discussion centers on the equivalency of a GAMBIT Dual Mode mission to a HEXAGON mission.
27 SLC-4E Launch Planning, 1981-1984 7/7/1980 10
A competing launch plan proposal for 1981-1984. Not written by NRO personnel.
28 GAMBIT Launch Options Aug-80 2
Cable response to a July 1980 cable indicating ongoing Dual Mode simulations and tentative recommendation for use of Vehicle 4351 for satisfying economic (agricultural) and drug intelligence needs.
29 SLC-4W Launch Planning Aug-80 1
Cable discussing an updated launch schedule that would protect a GAMBIT launch in early 1981.
30 Request for Data on GAMBIT and HEXAGON Performance Aug-80 2
Cable requesting the completion of multiple simulations (listed out) to assist in responses to intelligence community, Senate Select Committee, and internal NRO requests for information.
31 Fall Budget Guidance (Message 1) GAMBIT- HEXAGON Aug-80 2
Cable requesting assessment of multiple combinations of GAMBIT and HEXAGON vehicle launches between 1981 to 1985 to comply with DCI guidance levels.
32 1981 GAMBIT/HEXAGON Launch Options Sep-80 2
Cable providing an overview of options for GAMBIT/HEXAGON launch schedule for 1981.
33 SLC-4W Launch Planning Nov-80 2
Cable describing different launch options for missions 4351 and 4352 and timelines required for each one. Recommendations are included in the cable.
34 Suggested Film Load Nov-80 2
Cable describing the timelines required and the different film loads (5" or 9") available for Missions 4351 and 4352.
35 Film Load Information Dec-80 1
Cable describing and recommending film loads for Mission 4351 and 4352 depending on altitude.
36 SLC-4W Launch Planning Dec-80 1
Cable indicating the DCI requested continuous imaging capability and therefore the launch schedule for Dual Mode GAMBIT is moved to March 1981.
37 SLC4W GAMBIT Launch Planning Dec-80 2
Cable detailing status and support for a 26 February 1981 Launch of GAMBIT Mission 4351 or 4352. Deadlines are listed as well.
38 Dual Mode GAMBIT Dec-80 2
Cable summarizing two earlier cables about Mission 4351 and 4352 as well as HEXAGON 1217.
39 NRP Launch Plan 12/10/1980 1
Memo from Stansfield Turner to DNRO requesting a change in plan for GAMBIT Dual Mode.
40 SECDEF Launch Plan Questions 12/24/1980 2
Questions for the NRO about imagery continuity information for the March 1981 launch of GAMBIT Dual Mode.
41 Response to SECDEF Launch Plan Questions 12/31/1980 4
DNRO memo with responses to the Secretary of Defense' questions regarding the GAMBIT launch plan.
42 Retrofit of GAMBIT Vehicle 51 Jan-81 1
Cable discussing the conversion of GAMBIT vehicle 51 to Dual Mode and the timeframes for such an undertaking.
43 GAMBIT Collection Guidance 4351 and 4352 1/14/1981 6
COMIREX Collection guidance for GAMBIT Mission 4351 and 4352.
44 Alternative GAMBIT Vehicle 55 Budget Option Feb-81 1
Cable discussing GAMBIT Vehicle 55.
45 Launch Options for G-52 Feb-81 2
Cable discussing the timelines for launching GAMBIT 4352 depending on the type of mission required.
46 The KH-8 Camera System: Dual Mode Data Book Jun-81 77
KH-8 camera system reference book for analysts.
47 MFR Dual Mode GAMBIT Recovery 6/3/1981 2
Memorandum for the Record discussing procedures for recovery of the GAMBIT Dual Mode bucket.
48 GAMBIT/HEXAGON Launch Plan Nov-81 3
Cable draft discussing the film loads required for GAMBIT Dual Mode as well as the timeline foreseen to help avoid refurbishment needs for vehicle 52.
49 Mission 4352 Film Processing/Delivery Timelines Jan-82 1
50 Mission 4352 Film Processing/Delivery Timelines Feb-83
Cable approving the new delivery timelines for GAMBIT Dual Mode film.
51 MSN 4352 Film Processing Delivery Timelines Feb-82 1
Cable approving the new delivery timelines for GAMBIT Dual Mode film.
52 GAMBIT 4352-1 Recovery Mar-82 1
Cable providing information about the failure of the bucket to detach from the vehicle.
53 Dual Mode GAMBIT May-82 1
Cable reminding personnel about procedures in light of possible water recovery of 4352-2 SRV.
54 Performance Evaluation Team Report: Mission 4352/82 Flight Mission Characteristics Jan-84 232
A report evaluating the performance of GAMBIT Mission 4352.
55 GAMBIT Film Bucket (4352) Reentry Plan Sep-02 11
Briefing slides discussing the GAMBIT bucket reentry. Analysis, reentry procedures, actions and status are considered.
56 The Dual-Mode Gambit Mission 4352 2003 10
In this article, the authors describe an innovative operational approach employed in 1982 for GAMBIT Mission 4352. The unique mission profile attempted to remedy an imagery intelligence collection gap. The authors discuss the rationale, results, and lessons from this mission, and report on the story’s closing that unfolded two decades later in 2002.
57 GAMBIT Mission Factors No date 3
A working copy of a document exploring the issue of" Should GAMBIT 51 be launched in place of GAMBIT 52?"

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