Wildfire suppression costs have increased dramatically since 2000, currently averaging about $1.65 billion per year. Part of this rise is because residential development has expanded into areas that were previously wilderness, but it also may be a consequence of changes in weather and the accumulation of burnable wood and grasslands created by many years of aggressive wildland fire suppression, experts say.

The RAND study estimates the average social cost of a large wildfire at $3.3 million. Half of the fires cost less than $1 million and 10 percent cost more than $10 million. Fires near populated areas can be vastly more costly than fires in isolated regions. Large aircraft can help prevent these expensive large fires, easily justifying their annual cost if their activities account for the prevention of just a few large fires each year. 

The RAND study focused on 1,500-gallon and 3,000-gallon air tankers, 1,600-gallon scoopers, and 1,200-gallon and 2,700-gallon helicopters. The Forest Service asked RAND not to include very large air tankers, like converted 747s or DC-10s, which can carry tens of thousands of gallons of retardant. The study also excluded smaller aircraft that carry fewer than 1,000 gallons of water or retardant. 

Historically, the Forest Service's fleet of large firefighting aircraft has been composed primarily of air tankers and helicopters. Air tankers primarily carry fire retardant, which has advantages over water, but is also much more costly. There also are environmental concerns about the retardant. The key advantage of air tankers is their ability to support firefighting operations that may be far from the water sources needed by scoopers and helicopters. 

Scoopers can be used in areas where there is ready access to large bodies of water. Although current models cannot carry loads as large as air tankers, scoopers can cycle back and forth between bodies of water and a fire, making multiple drops an hour. This compares to about 1.5 drops per hour for an air tanker, which must fly back to a runway and load more retardant before returning to the fire. 

Helicopters also have the advantage of being able to make multiple trips in a short amount of time, and helicopters can make precise water drops. But helicopters have a limited range, fly slower than scoopers or air tankers, are less effective in mountainous areas, and cost more to acquire and maintain than scoopers on a per-gallon-delivered basis. The total annual capital and operating costs per aircraft range from approximately $2.8 million for a 1,600-gallon scooper to $7.1 million for a 3,000-gallon air tanker, before factoring in the cost of fire retardant, Keating said. 

Helicopters can use bodies of water as small as 12 feet in diameter. Scoopers need larger bodies of water, generally ranging from a quarter of a mile to eight-tenths of a mile in length, depending on obstacles adjacent to the water. RAND researchers found that at least two-thirds of the fires studied have been within 10 miles of a body of water that appeared to meet scoopers' requirements, and about 80 percent of fires have been within five miles of water bodies that would accommodate helicopters. 

The RAND report was delayed twice because the Forest Service and RAND agreed to develop a second analysis drawing on a Forest Service analytical tool called the Fire Program Analysis (FPA) system. As a result, the RAND study developed two separate, but complementary, simulation models to evaluate the effectiveness of fleet mix options. One is simpler and allows for better evaluation of the influence of model assumptions, while the other rests on Forest Service assumptions built into Fire Program Analysis system. "While the two models yielded different estimates of optimal fleets, both approaches suggested a predominant role for scoopers," Keating said. Another finding of the study was the importance of efficient prepositioning of aircraft to meet the next day's firefighting needs and what the researchers termed "dispatch prescience." 

When aircraft can be correctly and flexibly prepositioned, fewer are needed. Further, if aircraft dispatch can be optimized—that is, when they can be sent to just those fires where they make the difference between having a large fire or not—fewer aircraft would be needed. The Forest Service could dramatically reduce its aviation costs if it could increase dispatch prescience and prepositioning accuracy. "We think there may be an opportunity for the Forest Service to improve its aircraft location and dispatch algorithms, and possibly reduce aviation costs considerably," Keating said. 

The study does not recommend a specific number of aircraft, but provides a framework for the Forest Service to rebuild its fleet. Variables include how many days the aircraft would spend at particular base locations, the value of preventing certain fires and how accurately dispatchers can determine what kind of fire the Forest Service is facing. The range of solutions is on the order of 15 to 30 scoopers to be used in conjunction with two to six air tankers and a comparable number of 2,700-gallon helicopters. The study, "Air Attack Against Wildfires: Understanding U.S. Forest Service Requirements for Large Aircraft," can be found at www.rand.org. Other authors of the study are Andrew Morral, Carter Price, Dulani Woods, Daniel Norton, Christina Panis, Evan Saltzman and Ricardo Sanchez. 

U.S. Senators John McCain (R-AZ), Senator Bill Nelson (D-FL), and Senator Diane Feinstein (D-CA) introduced bipartisan legislation known as the Wildfire Suppression Aircraft Transfer Act of 2012 that would transfer 14 excess C-27J Spartan aircraft from the Department of Defense to the Forest Service to help replenish the agency’s aging airtanker fleet.  The Alenia C-27J Spartan is a medium-sized military transport aircraft. The C-27J is an advanced derivative of Alenia Aeronautica's G.222 (C-27A Spartan in U.S. service), with the engines and systems of the Lockheed Martin C-130J Super Hercules. The aircraft was selected as the Joint Cargo Aircraft (JCA) for the U.S. military. 

The United States Air Force plans to scrap the aircraft under its Fiscal Year 2013 Force Reduction Plan, but the Forest Service says the C-27J Spartan would become a vital component of its overall airtanker modernization strategy. These aircraft would provide a modern, flexible, and extremely efficient Type 2 platform specifically designed to operate in challenging conditions.  “The Forest Service needs to modernize its entire airtanker fleet,” said Senator John McCain. “We have an opportunity to take the C-27J, an aircraft the Pentagon no longer wants, and give it to the Forest Service to enhance aircraft safety and lower existing maintenance costs. The C-27J should be kept in the service of the American people to help our brave fire crews, rather than sit in an airplane boneyard.”  

Unlike past proposals that directed the transfer of excess military aircraft to private firefighting contractors, the legislation introduced by Senator McCain keeps the aircraft under Forest Service ownership and dedicates them solely to fighting wildfires.  The bill would also reauthorize a law that expired in 2005 that lets the Department of Defense sell surplus aircraft parts to private companies that perform maintenance on Forest Service aircraft.   

The C-27J's duties are to be taken by the U.S. Air Force's C-130s. In February 2012, Alenia warned that it would not provide support for C-27Js resold by the United States. In March 2012, it was reported that the U.S. Coast Guard is considering taking over the aircraft from the U.S. Air Force. On 23 March 2012, the U.S. Air Force announced that it will cut the C-27J from its inventory in fiscal year 2013 after determining that its per-aircraft lifecycle costs are higher than those of C-130 aircraft performing the same combat resupply mission. As of April 2012, the USAF is continuing to shut down the program, in anticipation that Congress will support its budget request to do so. In July 2012 the entire fleet was grounded due to a flight control system failure.