By Mark Bickham
While fighting a relatively small wildfire, (about 40 acres.) in the Wind River Range of western Wyoming, many years ago, the hand crew that I was attached to was struggling to build a fire line in the steep terrain.
The Crew Boss happened to be standing close by and was overheard to comment “Wish I could sprout wings and fly up to the top of this ridge and put in a line to stop this thing!” I remember thinking at the time, “Amen to that, brother!”
You see, back in those days the ground firefighters rarely saw any type of aircraft on a fire. As a matter of fact, the first aviation asset that I saw on a fire was an old Bell 47 helicopter that was delivering C-rations to the crews near the fire line; that was about all it could lift in the higher terrain of the western Rocky mountains. This was on my fifth fire assignment!
The aerial wildland fire suppression industry has certainly grown since those days, and has become quite effective in aiding the ground firefighters in their efforts to reduce the damage to our natural resources, as well as save lives and protect property.
Today, the firefighting aircraft that are available to fight wildland fires are quite extensive. The tools of the trade include all types of aircraft, from the DC-10 Very Large Air Tanker (VLAT) down to small general aviation airplanes such as the Cessna 172.
Although the specific missions may differ, they all serve a critical role in the overall effort to contain and extinguish wildland fires. So…with so many types of aircraft available to the fire suppression industry why use ag airplanes?
One of the most effective and efficient aircraft being utilized today are known as Single Engine Air Tankers (SEATs). These aircraft are current production airplanes that were originally designed primarily be agricultural application equipment. (With the single exception of the Air Tractor AT-802. This aircraft was originally designed to be an aerial firefighter, and is currently being used in both aerial application and fire suppression activities.) There are several manufacturers that produce aircraft being used as SEATs.
Most notably Air Tractor, Thrush Aircraft and also the Polish-made Dromader. In order to answer that question, we need to take a look at a little history and how we here in America fight wildland fires with airplanes.
The aerial fire suppression concept began in earnest back in the immediate post-World War II days. With the glut of surplus aircraft available at that time, the idea was put forward to use these assets in the same manner to fight fires as were used to win a global conflict. There were many ideas brought forward on how to best utilize this resource. Some were very good ideas, and some were quite bazaar.
One that comes to mind that was not well thought out to its conclusion, was the idea of dropping wooden barrels of water from high altitude. (We did have all these B-29s sitting around doing nothing, did we not?) The tests of “Carpet Bombing” with these barrels proved to be quite dangerous to any ground firefighters in the area!
However, cooler heads prevailed and surplus aircraft were modified to drop water onto the fire from a lower altitude without the cumbersome packaging. These first attempts in using airplanes to aid the ground firefighters in their efforts proved to be of great value. Even though there were a large number of surplus aircraft available at that time, the modifications and maintenance of these airframes became expensive, not to mention the building of a complete Air Tanker Base infrastructure to support their loading and deployment.
This cost kept the numbers of aircraft available down, and the locations where they were stationed became widely dispersed. This system is in place today and works very effectively, but the cost of maintaining a sizeable fleet to adequately cover the vast areas under a wildfire threat in this country can become prohibitive.
What was needed was an aerial resource that was less costly to maintain and operate as well as having the capability to respond to fire activity during the initial stages of the conflagration. This aircraft also had to have the capability to deliver an adequate payload of retardant or suppressant to the fire.
Enter the SEATs. During the early 1980s, there were several aviators thinking about this problem and began to explore alternatives. Some were beginning to think “outside the box”, looking to alternatives to the surplus aircraft fleet, as well as a way to mitigate the prohibitive cost of the development of a “purpose built aircraft” for aerial firefighting. A U.S. Forest Service employee wrote a “White Paper” describing the concept of modification to existing agricultural application aircraft for wildland firefighting.
The basic idea was to utilize an existing industry that could provide aircraft locally. As happens in large government bureaucracies, this paper was passed up the chain of command and was lost to almost everyone.
During this same time period, there was a small group of visionary aviators within the Department of the Interior with the same idea. One of them happened to see the “White Paper” on a desk and added it to his folder of ideas for future investigation. It was decided to develop a “Proof of Concept” program and seek out a method of demonstration. To make a long story short…the first demonstration of an ag aircraft making water drops on a simulated fire was performed by a Hemet Valley ag operator, with an unmodified Pezetel Dromader.
The year was 1984. The tests were deemed a success and that there should be further testing and capability parameters set before integration into the fire suppression effort.
After much discussion, it was decided to begin looking for opportunities to conduct a “Proof of Concept” demonstration on a real wildfire. That opportunity came several years later with the deployment of the first Single Engine Air Tanker (SEAT) on a fire in the Joshua Tree National Monument in southern California. The test was a success, and all who witnessed the application wanted to continue the use immediately.
As we all know, things move at glacial pace within the federal government and it was not until the last part of the 1980s that additional aircraft were being used to combat wildfires. These were almost exclusively being incorporated into the fire suppression resources of local Bureau of Land Management (BLM) districts in Arizona by forward thinking fire managers. Word began to spread throughout the firefighter community about the aircraft being used in the southwest to aid the ground firefighters on initial attack fire responses.
Soon, the numbers of SEATs being utilized on fires began to grow. With this growth, it became apparent there needed to be standardization of operational procedures, as well as equipment. Since the BLM had been the main agency to incorporate SEATs into their programs, it was determined it would become the “Lead Agency” in the development of this aerial resource. Soon, a list of equipment specifications, load capacity and performance criteria was compiled and adopted for all SEAT operations. These initial specifications are the foundation of what is now a National Aviation Program that is second to none.
The initial concept of SEATs within the wildland fire suppression effort was to have an aerial resource that would be capable of providing effective “Close Air Support” to the ground firefighter. The SEATs being utilized today must have a minimum load capacity of not fewer than 500 U.S. gallons. This is a minimum hopper capacity requirement; the vast majority of all SEATs today have a hopper capacity of 800 U.S. gallons.
They are required to have a gate system that provides the operator with the ability to equally split loads dropped. Many SEATs today have a computerized, constant flow, drop gate system mirroring the drop systems of the Large and Very Large Air Tankers such as the DC-10 and BAE 146s.
SEATs differ from their larger counterparts in that they have the capability to operate from smaller airfields and do not require separate dedicated facilities (Tanker Bases) for loading and deployment. Although, SEATs can and do operate from large air tanker bases, their greatest attribute is their ability to deploy from remote airports in proximity to the fire activity. This gives them the ability to respond to support requests more rapidly as well as being able to load and return to the fire in a short time span. Every SEAT has a dedicated service/support vehicle that in actuality is a portable fuel and retardant mixing and loading plant. A SEAT base can be quickly set up anywhere there is adequate runway and ramp facilities.
SEATs also are required to have a sophisticated communication system on board that is capable of communicating directly with both air and ground wildland firefighting assets. In addition, SEAT pilots are some of the most highly trained and capable aviators that have ever been inserted into the wildfire aerial environment.
Today’s SEAT program is the result of a lot of hard work by a large group of “forward thinking” individuals with a vision to the future. I would like to be able to mention them all here, but you guys know who you are and I thank all for your dedication and skills. When next we meet, the lemonade is on me.
By Mark Bickham