Helicopters attack fire from the air
Published 12:00 am Friday, July 26, 2002
- A Chinook helicopter takes off Thursday from the Baker Municipal Airport en route to help fight the Monument fire burning outside Unity. The choppers can haul 2,000 gallon loads of water to drop on fire hot spots. (Baker City Herald/Glenda Carter).
By JAYSON JACOBY
Of the Baker City Herald
Major Kit Jones threads his helicopter between sheer canyon walls while a 16,700-pound swimming pool dangles 70 feet below the belly of his big aircraft.
And that’s a routine mission.
It’s not a swimming pool exactly, but the bucket Jones hauls around with the Boeing CH-47 Chinook holds 2,000 gallons enough to fill a fair-sized pond.
Or about 30 of the roll carts you toss your trash into.
Every 10 minutes or so a flight engineer inside the Chinook triggers the bucket release, unleashing a torrent of water onto the flames and embers of the Monument fire south of Unity.
Jones’ craft is one of several helicopters, both military and civilian, dousing hot spots on the 24,700-acre blaze.
He flies for the Army National Guard at Stockton, Calif., and has piloted Chinooks over wildfires across the country during his 12-year career.
Jones is used to the sensation of 8 tons of water trying to pull his helicopter to the ground.
andquot;It puts the aircraft at its maximum gross weight of 50,000 pounds, but the engines are so strong there’s no major impact,andquot; Jones said.
Those engines are a pair of Lycoming jets that spin the Chinook’s twin rotors. Each rotor consists of three 27-foot-long fiberglass composite blades, spinning at 225 rpm.
Besides being able to hoist massive loads, the Chinook is a pretty fast flier, too.
But Jones said he slows down when he’s hauling a full bucket about 100 knots compared with a cruising speed of 135 to 150 knots when the bucket is empty.
The chief challenge for Chinook pilots isn’t the weight of the water, though, but the flame-spawned turbulence and erratic wind gusts common in the skies above wildfires burning in mountainous terrain, Jones said.
andquot;You’re flying close to the ground where there’s a lot more turbulence due to the heat,andquot; he said. andquot;And the winds tend to concentrate through canyons.andquot;
Although Jones downplays the effects of all that water, he admits he notices the difference in the helicopter’s response after the water has poured out.
When the bucket is full and he turns the Chinook, centrifugal force pulls the bucket in the opposite direction, Jones said.
He has to compensate for that to prevent the small oscillation from turning into a big one, like a child kicking his legs out on a park swing.
If the bucket sways too far, the 70-foot cable that connects to a stout hook on the bottom of the fuselage can touch electric wires in the helicopter, Jones said.
This is something to avoid.
Built to carry loads aloft
Chinooks have a total of three stout hooks attached to the fuselage.
The center hook is the strongest, and is the one the water bucket attaches to, Jones said.
The helicopters also can carry equipment by attaching slings to all three hooks, and Jones said those missions are more difficult for pilots than bucket work.
Sling loads are much bulkier than the bucket, he said; because they have a larger surface area, such loads sometimes andquot;try to fly themselves.andquot;
A full bucket, although heavy, also confines all the weight in a relatively small package that basically pulls straight down and doesn’t affects the helicopter’s andquot;controllabilityandquot; as much as sling loads, Jones said.
The National Guard Chinook carries a crew of four military personnel two pilots and two flight engineers and one civilian andquot;helicopter manager,andquot; said Sgt. 1st Class Steve Robertson, one of the flight engineers.
The manager works for the California Department of Forestry.
andquot;He’s the firefighting expert, and points out the best place to dump the water,andquot; Robertson said.
One of the flight engineers triggers the bucket release, usually at a height of about 50 feet above the tallest trees in the area, he said.
The pilot maintains a forward speed of about 50 knots during the drop.
That spreads the water over a wider area than if the helicopter was hovering, Robertson said.
Jones said the andquot;ideal dumpandquot; is one in which half the water hits the flames and half drenches the surrounding unburned area.
That way the downpour doesn’t just cool the hottest spot, but it also temporarily turns the tinder-dry zone around the flames into a more humid, tropical-feeling place where for a while at least the fire isn’t as active.
Back to Baker at night
After fighting the Monument fire during the day, Jones’ Chinook and some of the other helicopters assigned to the blaze return to the Baker City Municipal Airport to refill their fuel tanks.
The fleet’s presence has kept Dennis Christenson, the new fixed base operator at the airport, busy.
andquot;There’s been a lot of activity,andquot; said Christenson. andquot;It’s a good thing for the airport and the city.andquot;
In addition to selling fuel, Christenson said he’s renting a building to aircraft mechanics.
Some crews are staying in local motels and renting cars to travel between Baker City and the airport, he said.
Parked on the airport blacktop near a pair of Chinooks Thursday morning were two UH-60 Blackhawk helicopters.
The U.S. Army dispatched the two choppers from Fort Lewis, Wash., but not to pour water on flames.
The Blackhawks’ role is one their crews know well, but hope they don’t have to demonstrate: rescue.
One of the helicopter crews is on call around the clock in case a firefighter is injured and needs to be evacuated immediately from the fire area, which includes a wilderness area with no roads.
The four-person Blackhawk crews rotate, with one crew on duty for 24 hours straight while the other rests, said 1st Lt. Jennifer Mitchell, 24, a Blackhawk pilot for the past two years.
Crew members are equipped with night-vision goggles, and can embark on a rescue mission at any time of the day, in almost any weather conditions, Mitchell said.
So far their only flights over the fire area have been for training, and to learn the lay of the land, she said.
Each Blackhawk crew consists of two pilots, one medic and one crew chief.
Although the terrain around the Monument fire is rugged, with rocky peaks and deep canyons, it’s routine ground for the crew members, who are accustomed to missions such as plucking stranded climbers from 14,410-foot Mount Rainier, Mitchell said.
andquot;We’re used to the terrain,andquot; she said.