A wildland fire engine is a fire engine specifically designed to assist in fighting wildfires by transporting firefighters to the scene and providing them with access to the fire, along with water or other equipment. Most commonly used by the United States Forest Service, there are multiple types of wildfire apparatus which are used in different scenarios. According to the National Fire Protection Association, if the apparatus will be used primarily for outdoor and wildland responses, than it is to be considered a wildland fire apparatus and must conform to NFPA 1906.^[1]

Depending on where the engine is stationed it may carry as much as twice the national standard in fire hose. In areas where there is rugged terrain that keeps engines from driving directly to the fire, large hose lays are installed to transport water to the fire area. In desert areas with moderate terrain, less hose is used as it is easier to access the fire.^[2] Often the technique of pump-and-roll is used where the vehicle drives with the pump engaged while a firefighter uses a hose to spray water on the fire. This technique allows a team of two to flank the permitter of a fire.^[3]

Wildland engines are traditionally smaller than standard fire engines and are primarily used for vegetation fires or wildland fires. They also respond to emergencies in the back country where traditional engines cannot respond. Most wildland engines feature four-wheel drive capability and can thus climb hills and make it through rough terrain. One of the features that makes these engines ideal for vegetation fires is that they can pump water while driving, whereas traditional engines must be put into park to flow water. This pump-and-roll feature allows the engines to make "running attacks" on vegetation fires, a tactic that can help minimize the rate of spread by having a firefighter walk the edge of a fire with a hose line and the engine trailing close behind.^[4]

In the fall of 2007, the National Wildfire Coordinating Group agreed on a set of standards for all fire engines that are used for wildland firefighting. As structure engines are sometimes used on wildland fires, though primarily for structure protection, they are also included in the NWCG engine typing.^[5] Per the standards there are 7 types of fire engines.

Minimum Standards by Type^[5]

	Engine Type
	Structure		Wildland
Requirements	1	2	3	4	5	6	7
Minimum tank capacity	300 US gal (1,100 L)	300 US gal (1,100 L)	500 US gal (1,900 L)	750 US gal (2,800 L)	400 US gal (1,500 L)	150 US gal (570 L)	50 US gal (190 L)
Minimum flow rate GPM (LPM)	1,000 (3,800)	500 (1,900)	150 (570)	50 (190)	50 (190)	50 (190)	10 (38)
Minimum pressure	150 psi (1,000 kPa)	150 psi (1,000 kPa)	250 psi (1,700 kPa)	100 psi (690 kPa)	100 psi (690 kPa)	100 psi (690 kPa)	100 psi (690 kPa)
Hose types
2-1⁄2"	1,200 ft (370 m)	1,000 ft (300 m)	—	—	—	—	—
1-1⁄2"	500 ft (150 m)	500 ft (150 m)	1,000 ft (300 m)	300 ft (91 m)	300 ft (91 m)	300 ft (91 m)	—
1"	—	—	500 ft (150 m)	300 ft (91 m)	300 ft (91 m)	300 ft (91 m)	200 ft (61 m)
Pump and Roll

The Type 3 Engines are the most common type of wildland fire engine. While they traditionally have four-wheel drive to make driving over rough terrain easier, they can also be produced with standard rear wheel drive.^[6] Additionally the cab can either be 2-door or 4-door holding up to four people, but no fewer than three.^[7] Type 3s are required to have a minimum of 500 US gallons (1,900 L) of water, and be able to pump 150 gal/min at a pressure of 250 pounds per square inch (1,700 kPa).^[5] They have a typical GVWR of 26,000 pounds (12,000 kg).^[8]

The Type 4 engine trades a smaller pump and less house for a 50% larger tank. They are are required to carry a minimum of 750 US gallons (2,800 L) of water, but only pump 50 gal/min at a pressure of 100 pounds per square inch (690 kPa).^[5] The typical GVWR is at least 26,000 pounds (12,000 kg)^[8]

Type 5s are normally used as an initial attack engine atop a medium duty chassis. The GVWR of the chassis is around 20,000 pounds (9,100 kg).^[8]

Type 6 Engines are usually used as initial attack engines. They are build on a pickup truck frame with a medium duty chassis giving a GVWR of 9,000–16,000 pounds (4,100–7,300 kg).^[8] They are are required to carry a minimum of 150 US gallons (570 L) of water, but only pump 50 gal/min at a pressure of 100 pounds per square inch (690 kPa).^[5]

Type 7s are Patrol vehicle with a small pump and tank. As a light duty vehicle, they are in the range of 6,500–10,000 pounds (2,900–4,500 kg) GVWR.^[8] The vehicle has a small 50 US gallons (190 L) water tank are can pump 10 gal/min at a pressure of 100 pounds per square inch (690 kPa).^[5] pump and is a multipurpose unit used for patrol, mop up, or initial attack.

Additionally, there are requirements laid out by the National Fire Protection Association in NFPA 1906: Standard for Wildland Fire Apparatus.^[9] Some of the many details of the NFPA 1906 include:^[1]

• Stablity: All vehicles must pass a 30° stability test.
• Roadability: Vehicles must be capable of operating on 20% grades and remain stationary on 10% grades.
• Carrying Capacity: The Standard lays out a detailed analysis of what the allowable additional weight is on top of the gross vehicle weight rating. This in critical to keep the vehicles from getting overweight.
• Pump-And-Roll: Vehicles must be able to deliver 20 GPM at 80 psi while moving at a speed of 2 mph