Nike - Cajun

Nike-Cajun Rocket 

Introduction

The Nike-Cajun was a two-stage sounding rocket used for scientific research. It was developed in 1956 and launched until 1976, primarily by NASA and the military. Sounding rockets like the Nike-Cajun are used to carry instruments into the upper atmosphere and near-space environments to gather data for weather forecasting, atmospheric science, and even space exploration.

Wallops, Rockoons, and the Rise of the Nike-Cajun

By the mid-1950s, Wallops Island had become a hub for high-altitude research, launching rockets that pushed the boundaries of atmospheric science. But in those early days, not every method of reaching the upper atmosphere was a success.

One of the most promising—and sometimes frustrating—experiments was the Rockoon, a hybrid of rockets and balloons. The idea was simple: a large weather balloon would lift a small rocket high into the atmosphere, where the thin air would allow it to ignite and soar even higher, free from the dense drag of the lower atmosphere. The concept had its merits, but in practice, Rockoons were unpredictable at best and completely uncontrollable at worst.

At Wallops, engineers were looking for a more reliable way to reach high altitudes, and that’s where the Nike-Cajun came in. It was a two-stage rocket, combining the military’s solid-fueled Nike booster with a smaller Cajun upper stage, designed specifically for high-altitude research. The Nike-Cajun was powerful, predictable, and easy to launch—everything Rockoons were not. The first Nike-Deacon (a similar early version) lifted off from Wallops in April 1955, proving that solid rocket technology was the way forward for upper-atmosphere studies.

While Wallops was perfecting this new rocket, scientists like James Van Allen were still intrigued by the possibilities of Rockoons. In 1952, Van Allen and his team took a batch of Rockoons on a Coast Guard ship near Greenland and launched them from the deck. The results were staggering—they detected unexpected levels of radiation at high altitudes. This discovery would later lead to the identification of the Van Allen radiation belts, but at the time, it was just another strange puzzle piece in space science.

Despite these exciting findings, Rockoons remained tricky to work with. Unlike a ground-launched rocket, which could be aimed with precision, a Rockoon drifted with the winds before ignition, meaning it could end up firing in an unpredictable direction. Wallops, with its strict safety protocols and controlled test environments, found the method too unreliable. Instead, they doubled down on Nike-Cajun and similar designs, which became the backbone of high-altitude research for the next two decades.

In a final attempt to push Rockoons to their limits, the Air Force launched Project Farside in 1957—an ambitious plan to use a four-stage Rockoon to reach the edge of space. Scientists hoped to send a payload thousands of miles up, but poor tracking and unreliable data transmission doomed the experiment. The project was abandoned, and Rockoons faded into history.

Meanwhile, Wallops kept launching Nike-Cajuns, perfecting them with each test flight. What had started as a humble test range had now become one of the most reliable launch sites in the world. The transition from balloon-assisted launches to solid-fueled rockets was a defining moment for space research—and Wallops was leading the way.

While Rockoons may have been a wild idea with a brief moment of success, it was the Nike-Cajun and its successors that truly paved the way for modern atmospheric and space science. Today, Wallops' legacy lives on, built on the lessons learned from both the successes and failures of those early experiments.

Rocket Design

1. First Stage (Booster) - Nike M5-E1

   • Originally a military missile booster used in Nike surface-to-air missiles.

   • Burn time: 3.5 seconds.

   • Speed: Mach 3 (three times the speed of sound).

   • Separation: After about 1 mile (1.6 km), the first stage drops away due to aerodynamic drag.

2. Second Stage - Cajun Motor

   • Developed by Thiokol.

   • Burn time: 4 seconds.

   • Payload capacity: 50 pounds (22.7 kg).

   • Maximum altitude: 100 miles (160 km), above most of Earth's atmosphere.

Scientific Missions

Nike-Cajun rockets were used for:

• Weather research – Studying atmospheric conditions such as temperature and pressure at high altitudes.

• Ionospheric studies – Measuring how solar radiation affects Earth's upper atmosphere.

• Space research – Some missions studied conditions that would later help astronauts travel safely to space.

Famous Launches

• International Geophysical Year (1957-1958): Nike-Cajuns were used extensively to gather atmospheric data.

• 1970 Solar Eclipse Study: Nike-Cajuns were launched from Wallops Island, VA, along with Nike-Apache rockets, to study how the solar eclipse affected the upper atmosphere​.

Comparison to Modern Rockets

• Unlike rockets like the SpaceX Falcon 9, which send satellites into orbit, the Nike-Cajun was a suborbital rocket – meaning it went up and came back down rather than staying in space.

• While small, the Nike-Cajun helped pave the way for modern rocketry by testing high-altitude flight conditions.