Visual Aids Enhance Paratrooper Training

Article excerpt

Military services are increasing the use of parachute simulator to reduce injuries

In preparation for what would be a successful parachute jump in Yuma, Ariz., former President George H. W Bush trained in a simulator that gives paratroopers realistic perceptions of what actually happens during a mission.

The simulator, called Parasim, has been around for years, but recently has been upgraded to make it more portable and to meet new requirements of units such as the U.S. special operations forces.

Wearing a virtual-reality, head-mounted tracker and display, the trainee can scan a three-dimensional jump scene. The scenes can be based on real mission terrain digital data maps, and adjust in response to parachute toggle inputs and head motions.

The idea is for the trainee to get realistic perceptions of turning, drifting and maneuvering, for example. He can look overhead and react to simulated parachute malfunctions, scan in any direction to avoid collisions and conduct operations with other jumpers.

Jeff Hogue, the inventor of Parasim, said that this technology is useful for mission planning and rehearsal. Hogue works for the company that makes the trainer, Systems Technology Inc.

For military mission planning, the digital satellite imagery comes from the National Imagery and Mapping Agency, complete with wind fields, which reflect the location and forecast weather, said Hogue.

Hogue told National Defense that practicing how to deal with malfunctions in the parachute and unexpected scenarios can help minimize injuries and fatalities. Many of the jumpers do not get to train in the actual environment where they have to carry out their mission, said Hogue.

An accomplished jumper has to react to contingencies with a trained response, almost like a reflex, he said. And that is exactly what this simulator does: it injects as many failures as possible into the mission and teaches the jumpers how to quickly react and correct them, said Hogue. Operational parachutists usually have a reserve parachute, but aircrews who have to eject in an emergency, for example, sometimes have just one device.

Jumpers only have seconds to realize that their chute is malfunctioning, before they tumble to the ground at a speed of hundreds of feet per hour.

It is vital for a parachutist to properly be trained to check parachute deployment and controllability, to be able to identify specific malfunctions and immediately follow the required correction procedure, if necessary, said Hogue.

Harnesses, toggles and risers are in place in the simulator. But instead of having the actual parachute, once harnessed to the trainer, the jumpers have to wear the virtual reality head-mounted display that allows them to scan the scene.

"On the back of it is a tracker, which keeps track of where you look, and then the computer computes the proper image for the direction you are looking," Hogue explained. "That way, if you look up you can see your parachute; if you look down, you can see where you are. If you look around, you can find the other guys you are jumping with."

Parachutes deploy by pulling out the rip cords, said Hogue, so the parachute in the trainer "has rip cord capability, and when you pull on them, you get your parachute out." That action is simulated on the computer.

To teach trainees how to deal with faulty parachutes, he said, "We make them deliberately defective and you can correct it by pulling on the straps that you get suspended from. ... Up on top of the straps are sensors and those sensors know if they are being pulled down on. …