(updated @ 12:12 p.m. MT, Dec. 1)
The U. S. Forest Service, apparently in response to criticism from the Los Angeles County Fire Department and the Los Angeles County Board of Supervisors, is again considering using water-dropping helicopters at night.
The USFS experimented with night flying in the 1970s, but abandoned it after a helicopter collision and since then has said it is too dangerous to fly helicopters 30 minutes after sunset.
The Associated Press reports that USFS Fire and Aviation Management Director Tom Harbor said:
“We are in the process . . . of one more time taking a look at night-flying operations. But we will have to make sure that those operations, before we change our policy, are worth the benefits.”
In a report they issued on November 18, the LA County Fire Department criticized the USFS for not using helicopters at night during the early stages of the August-September 160,000-acre Station Fire near Los Angeles that killed two LA County firefighters.
In 1977 two night flying helicopters collided, one operated by the USFS and the other by the Los Angeles County Fire Department. The helicopters were preparing to land at a water reloading point. Both pilots were wearing night-vision goggles. One of the pilots was killed, and the other sustained serious injuries.
After that collision, some pilots abandoned night-vision goggles for a while, or wore them only during certain phases of the mission. The goggles produce “tunnel vision”, providing a narrow field of view and very little peripheral vision. If a fire has a significant amount of flames, enough light is sometimes available in the active fire area that night-vision goggles are not necessary to actually make the water drop, but may be required flying to and from the drop area.
Several fire agencies in southern California currently use helicopters to suppress fires at night, including Los Angeles County, San Diego County, and Kern County. San Bernardino County operates helicopters at night for law enforcement operations, but the last we heard, they did not use them on fires at night. Orange County recently bought $25 million worth of specially equipped helicopters so they could operate at night, but a dispute with their union has kept their ships grounded after dark.
One of the modifications that must be made to a helicopter in order to be used with night-vision goggles is to enable the instrument panel lights to be adjusted to a very low level, because the goggles magnify all light by hundreds of thousands of times. Normal panel lights would overwhelm the goggles.