Night Helitack
Wearing special goggles that enable them to see in the dark, helicopter pilots are now making night flights to fight wildfires. Helicopter fire attacks (helitacks) have become a major method of reducing forest and brush fire losses.
Research into the development of safe night flights for helicopters began in 1973 when Congress provided funds for the U.S. Forest Service to carry on the necessary experimental work. The research program was sponsored by the Forest Service’s Pacific Southwest Forest and Range Experiment Station at Berkeley. CA, but development work was done by the Forest Service’s Equipment Development Center at San Dimas in southern California.
Helicopters have been used by the Los Angeles County Fire Department in fire suppression for several years—in the daytime. Helicopters are more flexible than airplanes, can get into remote canyons. hover over hot spots, and serve as a “spy in the sky” to report on the fire conditions.
Herbert J. Shields, the Forest Service’s helitack project leader says, “Our intention is to eliminate the restrictions that nightfall ordinarily inflicts on the incident commander. At the same time, we want to help him take advantage of the lower temperatures and wind speeds that usually exist on wildfires at night.”
The helitack program is the first public sector application of nighttime helicopter navigational aids developed by the military during the Vietnam War. explains Shields. These battery-operated, night vision goggles make navigation possible by amplifying available night-time light.
The approach has been to train turbinequalified helicopter pilots to safely navigate to wildfires at night.
Of all the devices that have been looked into, the night vision goggles developed for the military by ITT have been the most useful. These battery-operated units are compact and are completely self-contained. The goggles weigh less than two pounds and can be mounted on helmets worn by the helicopter pilot and co-pilot. The units amplify starlight, moonlight, or artificial light, giving the pilots a view of whatever is ahead. Most pilots need to work with the goggles for about five hours before they become adept at picking up visual cues from the unfamiliar, all-green world they see on the miniature viewing screens contained in the goggles.
Another night navigational device used successfully is FLIR (forward-looking infrared) scanner. This equipment is mounted on the helicopter’s nose, projecting a daylight picture of whatever is in the infrared scanner’s field of view onto video screens in the cockpit. The FLIR works day and night, penetrates smoke and haze, allowing the helicopter pilots to work safely in the dense billows of smoke which hang over forest fires. FLIR has only one serious limitation—it isn’t usable in heavy fog or a similar weather condition. Whatever is seen on the FLIR can be recorded for playback at the fire camp or at a training session.
In addition to the night vision goggles and FLIR, an infrared light attached to the underside of the aircraft is just right for illuminating canyons and other places where adequate natural light is insufficient for navigation.
The night navigational equipment is now mounted on Los Angeles County Fire Department’s helicopters, whose pilots are making effective water and chemical retardant drops on wildfires at night.
Aside from providing the usual fire suppression support, the helicopters are also proving to be excellent spotters for the mop-up ground crews after the fire has been put out. Flying the periphery of the burned area, helicopter crews have been able to spot burning embers outside fire lines, embers that are not visible to ground crews. Such spy in the sky activity is important in preventing the start-up of new fires after the ground crews have left the scene.
Fire suppression is not the only role played by the Los Angeles County Fire Department’s helicopters. They are now rendering valuable services for emergency medical evacuations and for nighttime search and rescue missions.
