Student Features

Reaching Out To Help
10.01.03
A Coast Guard helicopter rescuing a person stranded in the ocean.
A Coast Guard helicopter makes an ocean rescue.

It's one of the best ways to rescue someone: extend a pole. The victim can grab on and be pulled to safety with less risk to the rescuer. Pole rescue is a common method of helping people caught in burning buildings and in boating accidents. A pole, extended from a helicopter, helps steady the victims as they're brought in to safety.

There are drawbacks to this rescue method, though. A helicopter's blades create a great deal of turbulence, both in the water and in the air. The turbulence can cause unsteadiness in the rescue vehicle, create strong winds, and hamper rescue efforts. If the rescue pole becomes caught in the helicopter blades, the mission fails, and the helicopter could crash. It's risky business.

Developers at NASA's Ames Research Center in California have shared a new idea with the United States Coast Guard. It's a telescoping rescue boom for helicopters that could safely remove people from the sea, beyond dangerous downwash waves, or from high-rise building fires. The boom extends the helicopter's hoist cable from the front of the aircraft and beyond the main rotor. Currently, Coast Guard divers must risk dropping into the ocean from the middle area of hovering helicopters to rescue people who otherwise could drown in turbulent waves created by the helicopter's main rotors.

A Coast Guard helicopter performing a rescue in the ocean.
A helicopter rescue at sea.

Nicknamed "the fishing pole," the 27-kilogram (60-pound) boom is hollow and made of reinforced plastic. The device is designed so that once the rescued person is hooked onto the cable end, the victim's weight pulls the cable free from the boom through a series of quick-release eyelets. The person is winched up to the helicopter in the typical way, yet is free of the boom. The cable results in the boom never carrying the rescue weight, which is a major deficiency of standard methods, says Dr. Len Haslim, an Ames researcher.

The fishing pole features a lightweight device that extends and retracts the telescoping boom. A flat metal ribbon roll unreels and wraps around a wire rope that also unwinds from a spool to form a rod. The rod is stiff enough that it can push or pull, and the rope keeps the metal ribbon from kinking as it extends and retracts. The entire boom can pivot, if needed, so that rescues can be made from the side, as well as the front, of an aircraft.

This flexibility and strength allows the boom to reach onto ships between obstructions to lift a patient. When reaching into high-rise building windows to rescue people, the danger would be reduced because the helicopter wouldn't be as close to fires, and wouldn't be creating windstorms of its own.

In addition to the helicopter boom's construction, it also features an electronic light system to aid rescues. Intersecting red and green light beams can be used to help the crew locate a proper safe blade-to-tip distance from obstructions or from the victim. Using this device can improve the rescue capabilities of helicopter crews that confront rough seas, mountainous terrain, and tall building fires, Haslim says. The helicopter boom can carry as much as 272 kilograms (600 pounds).

With adaptations, the concept can be used in space, Haslim says. Astronauts could use a modified boom to safely dock one spacecraft to another.

Courtesy of NASA's Aerospace Technology Enterprise
Published by NASAexplores