Explosive Technology's Space Age Jet-Axe, Circa 1972

By Norman Chan

Need to bash down a door? Why not use an explosive charge?

We've previously written about NASA Spinoff, the annual magazine published by NASA to educate the public about real-world applications of research and technology originally developed for space exploration. The Spinoff magazine is still published today, though NASA has many more avenues to sharing that information, like YouTube, Twitter, and even its Spinoff website. The Spinoff Wikipedia page claims that NASA has 1600 products in its Spinoff database, dating back to when the magazine was founded in 1976. Technologies like water purification systems, temper foam, and safety grooving on highways are well-known innovations credited to NASA. (Tang, however, is not one of them.)

At a recent visit to the Prelinger Library in San Francisco, I found a 1972 book called Space Age Spinoffs that pre-dates NASA's Spinoff publication. It's a collection of two dozen NASA inventions and stories of how they were used outside of NASA, but in the context of the early 1970s technology. That's what made this book so fascinating--some of the entries stretched the definition of practical use (lunar walkers as alternatives to wheelchairs) while others were definitely a product of the times ("G-Suit Saves a Charming Lady!"). There were entries for high-calorie space food bars (precursors to energy bars), rudimentary wireframe computer models for medical diagnoses, and even zero-gravity simulations for physical therapy. But my favorite discovery was a invention created for firefighters that used NASA-grade explosives: the Jet-Axe.

The Jet-Axe, a very real product made by a company called Explosive Technology (seriously!), was intended for use to punch precise holes in walls, doors, and other obstacles. Instead of using a normal axe to try to smash through a steel garage door, for example, firefighters could hang the Jet-Axe--which was a essential a packaged explosive--on the door and trigger an explosion to punch a rectangular or circular hole. These holes would be used for ventilation of hazardous fumes or for forcible entry into buildings.

According to a government issued document about the Characteristics of Non-Military Explosives, The Jet-Axe was filled with between two and six ounces of RDX (aka cyclonite), which was developed as a stronger-than TNT explosive. Explosive Technology may have underestimated the volatility of its product, and according to one Firefighter historian, the Jet-Axe was removed from use after they started unexpectedly going off in ladder trucks.

A few more photos of the Jet-Axe from the Spinoffs book below, including a print advertisement for the Jet-Axe in a Fire Engineering trade publication.