The Forest Service has tried to harness the power of the airplane from the moment it was invented. In 1919, several Air Service Curtiss JN airplanes Jennies" and pilots patrolled the forests in California and Oregon to provide early detection of fires. The first recorded water drop in 1930 use a Ford Tri-Motor airplane and a wooden beer keg filled with water.
During the 1930s, techniques were developed to deliver cargo by parachute to firemen on the ground, although lighter equipment (such as sleeping bags) was free-dropped. Rumors abound that in 1931 the legendary Charlie Red Jensen released water from saddlebags strapped to his biplane over a California fire.
By 1940, smokejumpers were parachuting into wilderness locations to dig containment lines around remote fires. But the successful combination of technology, personnel and procedure for direct fire control eluded the Forest Service. Dropping barrels or balloons of water was deemed to be more hazardous to the firefighters on the ground than to the fire itself.
World War II created a transformation in fixed wing aircraft capability and a surplus of pilots willing to push the edge of their flight envelope. Simultaneously, Americas growing population was spreading out, increasingly living in wildland-urban interface zones and raising the urgency of solving the wildfire issue.
In 1954, a number of federal and state fire agencies held a test program called Operation Firestop at MCB Camp Pendleton. During Firestop, a former Navy Grumman TBF Avenger performed a free-fall water-drop, soaking 250 feet of runway. It wasnt spectacular - but it ignited the imagination of Joe Ely. Due to the large number of ag flying services located near the MNF headquarters, authorities immediately envisioned the use of modified crop dusting aircraft for fighting wild fires using a similar water cascade technique. Ag biplanes were rugged, highly maneuverable and used to carrying liquid cargo. Combined with the skilled ag pilots, these water tankers with wings could fly at slow speeds close to the ground while releasing their liquid cargo with a reasonable degree of accuracy.
In July 1955, an early pioneer in aerial firefighting talked to a resourceful stunt pilot for the motion picture industry, who then cut a hole in the bottom of a Boeing Stearman 75 Kaydet (N75081) underneath the rice hopper (in lieu of a front seat) that was used for seeding operations. He added a one-foot square water release gate with hinges, a snag and pull-rope so the pilot could open and close the gate when required. At a practice demonstration soon thereafter, they set the dry grass alongside the runway on fire, the pilot then flew over, released the 160-gallon water burst, and extinguished the blaze. Airtanker number 1, referred to as an aerial firewagon by the local press, was now in business.
The first airdrop on an actual wildfire was made during the Mendenhall Fire, August 13, 1955, in the Mendocino National Forest. Vance Nolta flew this historic mission in the Stearman, dropping 6 loads of water in support of firefighters on the ground trying to contain the blaze. This operation was considered so successful, Americas first fire pilot Vance, worked another fire the very next day.
By the summer of 1956, 7 biplane borate bombers had been modified to handle retardant drops during the dry summer and fall months. The original Stearman was joined by several N3Ns, which could carry a bigger load of slurry. These N3Ns had been the primary training planes for US Navy pilots during World War II and many pilots knew how to fly them well. Frank Prentice built an N3N into air tanker number 21 and flew it until 1963.
Local MNF Forest Service rangers requested air support by just radioing their needs into the dispatch office. The dispatcher, would then call one or more of the contracted flying services to provide the location of the fire plus what airstrip might have reloading capability. Soon, rangers from all across the state began dialing Willows 80 asking for help. The fledgling Aero Fire Squadron fought 25 fires all over the state that summer, and their success was duly noted.
In 1956, more water drop tests revealed that on hot or windy days, plain water barely made it to the ground unless the pilot flew hazardously low. Forest Service personnel created a more effective solution, using a slurry of sodium calcium borate mixed with the water. After the 1956 season, it was discovered this borate mixture sterilized the ground upon which it landed. The Forest Service then switched to mixing bentonite with water for a few years (however, the airtanker industry was stuck with the term borate bomber by the media for many years after). Some fires were so large, the airtanker loads were mixed in cement trucks sent to the airstrip to assist!
The pilots quickly learned how to work with ground forces to create an effective fire control line. Even the air attack pioneers were adamant that aircraft were just another tool in the in the firefighters kit, not a solution all by themselves. When more than one aircraft was required to suppress a fire, Ely would fly in the front seat of a Piper Tri-Pacer flown by Lee Sherwood. Acting as the air tactical coordinator, he would have the pilot waggle his wings to point out locations where he wanted the slurry dropped.
By 1957, the Forest Service realized air attack was a valuable weapon to have in its fire control arsenal. But these biplanes were just too small to carry more than 120 gallons of the heavy bentonite retardant and were useless on large project fires. They also couldnt support modern avionics such as state-of-the-art tactical radios and IFR instruments. Even with beefed up motors in these slow biplanes, it took 8 hours for a Willows-based tanker to fly to southern California, so a whole day was lost trying to contain a fire. Neither the Federal nor state agencies wanted to fund an armada of tiny tankers buzzing around large fires, dropping small loads from perilously low heights.
To increase the effectiveness of fire control operations, the Forest Service engaged with other better-funded contractors for more expensive but larger and faster aircraft. Many Navy TBMs were converted to handle slurry drops, becoming the first aircraft dedicated solely to aerial firebombing and capable of dropping 600 gallons of retardant on a single sortie. The TBM Avenger recently restored and put on display aboard the USS Hornet Museum was a Red Jensen firebomber for many years in the early 1960s.
As the 1960 s progressed, it was clear there were many types of aerial fire fighting missions. Big project fires, especially ones in thick forests or at higher elevations, raged unchecked because of limitations with single engine airplanes. The Forest Service and California Division of Forestry contracted with companies for an even wider variety of military surplus aircraft. These multiengine PBYs, B-24s, A-26s, DC-6s, and even B-17s could carry up to 3,000 gallons of retardant and were much more effective on large fires.
Though the feisty agricultural pilots proved that wildfires could be fought from the air, they were nudged out by the bigger, faster airtankers with specialized crews. By 1964, they had disappeared from the airtanker program. Their pioneering work of fighting fires finished, many of these pilots continued to serve the local farmers by sowing and spraying the rice fields of the northern Sacramento Valley for years afterwards.
Like their WWII training biplanes, these pioneers of aerial firefighting have mostly faded into the history books. In 1982, the 25th anniversary of the first water drop on the Mendenhall Fire, the Forest Service honored them with a ceremony and a plaque at the Willows Airport.