Historical Context of the D-21 Program

Dr. James D. Outzen

Director, Center for the Study of Reconnaissance

(As prepared)

Despite the United States first successfully launching signals collection and imagery reconnaissance 

satellites in 1960, the National Reconnaissance Office would continue to seek solutions to a pressing 

problem—how to gain intelligence from space during an international crisis. 

As a historian, part of my responsibility is to describe the historical conditions and factors that lead to

matters of historical significance. That is what I hope to do briefly this evening by providing the 

historical context for the investment in the D-21 drone program by the United States through the 

National Reconnaissance Office, the nation’s agency for developing, launching, and operating the 

nation’s reconnaissance satellites. 

The United States launched its first successful reconnaissance satellite in June 1960. The satellite was 

known as the Galactic Radiation and Background or Grab satellite. It was intended as an experimental 

satellite to test whether or not the US could detect Soviet radars from space. It proved to be even more 

successful than simply proving the US could detect the radars—it identified types of radars and coverage 

of those radars—critical intelligence information if the US needed to carry-out a retaliatory attack in 

response to a Soviet first strike using nuclear weapons. 

To identify where those weapons—Soviet ICBMs—were located, the US successfully launched a photoreconnaissance satellite in August 1960. The satellite was known in classified circles as Corona. Before 

Corona, the US had no reliable means for comprehensively understanding the development pace for 

Soviet nuclear forces. For the first decade and a half after World War II the United States depended on 

peripheral flights near Soviet and Warsaw pact nation borders to try and image or pick up signals 

associated with Soviet nuclear weapon development and deployment. Those aircraft could offer no 

intelligence of value concerning activities deep within the vast Soviet land mass. Beginning with its first 

successful test flight in 1955 through the downing of the Gary Power’s piloted U-2 over the Soviet Union 

in 1960, the US developed a limited means for gaining intelligence on the areas denied to regular and 

comprehensive observation. Finally, the US had developed very limited intelligence from human 

sources within the Soviet Union during the 1950s and 1960s. 

Satellites like Grab and Corona would quickly provide the most comprehensive understanding of the 

Soviet nuclear threat posed to the United States. For example, the first Corona satellite returned more 

imagery of the Soviet Union from its first mission, than all the missions over the Soviet Union by the U-2. 

By the late fall of 1960, the director of the Defense Department’s national reconnaissance program was 

able to report to President-elect John Kennedy that the Soviet Union had been imaged to the point that 

he could confidently conclude the Soviet Union did not possess more strategic nuclear weapons than 
the US—a conclusion that could not have been reached even three months earlier based on available 

intelligence at that point in time.

Despite the rapid and impressive gains in intelligence on the strategic nuclear threat by reconnaissance 

satellites, the United States remained vulnerable to surprise actions by the Soviets and others, surprises 

that quickly arose such as the one described in this newsreel from 1962..

The Cuban missile crisis demonstrated the limited means for the United States to gain intelligence 

during a crisis. There were no satellite imagery or signals collection resources available during the 13 

day crisis. The United States depended on aerial observation, but this means brought the crisis to a 

peak on 27 October when forces on Cuba downed a U-2, a previously declared redline for carrying out a 

military response by the US. Demonstrating great patience, President Kennedy instead sought more 

information on the downing of the U-2 allowing for both sides to step back from the precipice of 

exchanging nuclear weapons. The Cuban missile crisis reinforced the United States’ determination for 

developing a reliable means of gaining intelligence during a crisis from denied areas. 

Other events would follow such as the Six-Day war between Israel and neighboring Arab nations in 1967. 

Like with the earlier Cuban missile crisis, information on opposing forces was limited and gaining 

information using conventional military resources was fraught with risk. In the 1960s US imagery 

satellites returned their images on film from space. They were only on orbit for limited periods of time 

each year. Because of these limitations and others, satellites were often not available to capture 

intelligence to assist in managing a crisis.

In some instances those, such as the 1968 invasion by Soviet Forces to put down liberalization efforts in 

Czechoslovakia, the US did have an imagery satellite in operation during the crisis. The satellite in fact 

captured images of the Soviet forces massing along the Czech border prior to the invasion. 

Unfortunately those images were not deorbited and developed for examination by intelligence analysts 

until after the invasion had occurred, providing no warning. 

As a consequence of limited information about vast denied areas of the earth, the United States 

persisted in developing technical means for collecting intelligence over those denied areas. One of 

those means, developed and tested by the National Reconnaissance Office was the D-21 drone. My 

colleagues this evening will discuss more about the D-21 program and its significance. The need was 

real and pressing in order to provide critical intelligence for the President of the US and other senior 

leaders to make informed decisions. 

Eventually the US would obtain more reliable means for gaining crisis intelligence and more 

comprehensive intelligence. The backdrop for deciding on this program was yet another crisis in the 

Middle East. During 1970 tensions between the Israelis and Egyptians and other Arab forces resulted in 

nearly daily military exchanges in the Sinai. The Nixon administration pressed cessation of military 

activity, putting heavy pressure on the Soviet Union to discontinue arms shipments to the region. Nixon 

was very frustrated because he could not obtain regular intelligence during the crisis to affirm the 
Soviets had stopped shipments as they had committed to. By 1972 still influenced by the 1970 crisis, 

Nixon approved a new satellite that would incorporate yet undeveloped technology for obtaining 

reconnaissance images from space in near-real time. Some four years later, that satellite, known as 

Kennen (the German verb “to know”) was successfully launched. For the first time, the US would have 

reliable near-real-time intelligence for use during a crisis. This breakthrough brought capability that was 

hoped for from the D-21 program—intelligence information that would displace uncertainty to better 

preserve the security and peace of the nation.