The newest jetpack won't help you realize your dreams of soaring across the sky, but it could help you run a mile in just four minutes.
The prototype jetpack, which is still undergoing testing and development, is lightweight, battery-powered and worn much like a backpack. The futuristic-looking device has so far enabled one wearer to shave about 20 seconds off his time when running a mile around an outdoor track, according to Jason Kerestes, a graduate student of engineering and robotics at Arizona State University who leads the jetpack project.
Without the jetpack, the speedy test subject ran a mile in 5 minutes and 20 seconds. But when wearing the device, the same runner clocked in at 5 minutes and 2 seconds, and he was able to maintain a lower heart rate while running, Kerestes told Live Science.
The jetpack, which has been dubbed the "4 Minute Mile" (4MM) project, was originally developed for the military's Defense Advanced Research Project Agency (DARPA) as part of a program to get soldiers moving more quickly on the battlefield. The technology has a ways to go before it realizes its four-minute mile goals, but they are still within reach, Kerestes said.
To get the jetpack up to speed, the researchers are taking a closer look at the physics behind the device. Like most jetpacks, the one developed by Kerestes and his team operates by generating thrust, or a propulsive force that moves the person wearing the device forward at a faster pace. In order for the jetpack to have any effect, it must create enough thrust to make up for its own weight, Kerestes said.
"When the jetpack is on your back, it's creating about 15 lbs. of thrust, which is essentially like somebody pushing you from behind with about 15 lbs. of force," Kerestes said.
But the key to making the jetpack even more efficient doesn't necessarily lie in increasing the amount of thrust it produces, said Kerestes, who explained that there's a "sweet spot" for the right amount of thrust.