Douglas A/B-26 Invader

Becoming an Air Tanker Pilot

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An airtanker, while initially assigned to one operating tanker base, is considered a National asset.  This means that while you may be assigned to Boise, ID as your primary contract base, the National Interagency Coordination Center could dispatch you to another tanker base if the fire situation at that area calls for more aerial assets.  The relocation could be for an undetermined time depending on fire activity.  You may never see your assigned base again that summer.  This is where a crews flexibility and ability to adapt become important.  It is essential that crews remain professional and courteous to the customer throughout the fire season.  Flight crew performance and their ability to satisfy the customer are critical to a companys future efforts to win follow-on contracts.

Airtanker crews work a six-day on, one day off schedule.  The day off is scheduled at the beginning of the contract and generally doesnt change.  If you have Wednesdays off, that typically remains the case throughout the contract period except for a few limited exceptions.

Duty hours are a minimum of 9 hours a day up to a maximum of 14 hours a day, depending on the fire danger conditions.  During the standby hours, you will be at the airtanker base and ready for dispatch, much like fire engine crews at station houses.  Hobbies are encouraged, within reason.  Flight hours are limited to 8 hours a day, but it generally takes all 14 available hours to reach 8 flight hours since crews usually do not start flying when first reporting in the morning and flight time is lost to periodic refueling, and the reloading of retardant on each evolution.

There is no guarantee of when (or if) youll go flying or where youll end up when you do launch.  If a dispatch is received, the airtanker is to be airborne to the incident within 15 minutes, not withstanding delays for flight planning for out of the area flights, ATC delays, etc.  This mode of operation drives a couple of lifestyle issues that are sometimes hard for crews to adjust to.  For example, a crew may have rented an apartment or a hotel room, or towed a house trailer to their assigned tanker base.  They can be dispatched at any time to relocate to another base.  The assignment may be for a day, week, or indefinite, depending on the progress of the fire activity in the dispatched area.  The schedule can play havoc with plans (and food left in the refrigerator), and often lead to double expenses (your lodging at your assigned base and your hotel room where you were dispatched).  Additionally, the stress on families from the separation and uncertainty of your location can present challenges.

While the pay and benefits vary between operators, you can estimate that youll make (gross wages) between $35,000 - $45,000 over an average contract and fire season.  Your pay consists of standby pay and flight pay.  The standby pay is fixed, but flight pay can fluctuate greatly based on the severity of the fire season.  Generally the more you fly, the more you make.  It is all up to Mother Nature and beyond anyones direct control.  There have been years that many airtankers flew over 300-350 hours.  There have also been years that some airtankers only flew 50-60 hours.  Moreover, some airtankers may fly more than others because of the varying fire danger from one region to the next.

How long will you be a Co-pilot?  Generally speaking, when you get hired in this Industry you start at the bottom and work your way up.  Depending on your experience, your ability and attitude, and the operators need, you should expect to be in the right seat for a minimum of 3-5 years.  The realistic average is probably closer to 8-10 years.  There are no guarantees.

The information provided in this short summary of the life of an airtanker pilot has been realist and straightforward to allow you to make an informed decision on whether this is the profession for you.  The airtanker pilot is one of the most challenging, rewarding, fulfilling flying jobs that exist.  It requires superb aviation skills, dedication and courage.  There is no room for hotdogs, thrill seekers or short timers.  If you want a rewarding flying career, the airtanker pilot is where you want to be.

Flight Crew Requirements

Airtanker Pilot-in-Command (AKP) shall possess:

  • FAA Commercial Certificates
  • Class II Medical Certificate valid through the contract mandatory, pre-season and post-season periods.
  • FAA instrument rating for airplanes
  • Category. Class and Unrestricted Type Rating in aircraft to be flown.
  • Recent flight experience: Airtanker Pilot-in-Command requirements of Federal Aviation Regulation Part 61.58(a) and instrument currency requirements of Federal Aviation Regulation Part 61.57 (c), (d), or (e) proficiency check.
  • Proof of completion of the Forest Service Airtanker Pilot Training Program or completion of the National Aerial Firefighting Academy course.
  • Proof of qualifications to meet Federal Aviation Regulation Part 137.53 for congested areas. Applicants not meeting FAR 137.53, congested area requirements, may be issued an AKP card provided the limitation is noted on the card by the pilot inspector and a qualified Initial Attack Pilot is assigned to every mission.
  • A current Forest Service or OAS Agency Pilot Qualification Record Card issued by a USDA/USDI approved Inspector of Pilots.
  • Following flight experience:

- Total time-all aircraft

1500 hours

- Pilot-in-Command-airplanes

1200 hours
Pilot-in-Command Breakdown
  • Make and model to be flown
25 hours 1
  • Category (airplane) and class (multi-engine) to be flown
200 hours
  • Multi-engine aircraft over 12,500 lbs, if applicable all
    time must be accumulated after receiving type rating
100 hours 2
  • During preceding 12 months-airplanes
100 hours 3
  • Actual or simulated instrument time (minimum 50 actual)
75 hours
  • Night flying to include at least three takeoffs and landings to full stop during the 90 days preceding annual Pilot approval in category and class over 12,500 lbs
100 hours
  • Typical terrain and landing facilities-mountain and low
200 hours
  • During 60 days prior to annual agency Pilot inspection
5 hours 4


  • In make and model, to include five takeoffs and landings
    performed from the left seat



  • Demonstrate dropping one full load of water in typical
    terrain under the observation of a designated Pilot
    Inspector in a minimum of one make and model airtanker
    to be flown



  1. The 25 hours of Pilot-in-Command required must have been within the past 5 years with an Unrestricted Type rating in make and model to be flown. (The time must be accumulated after the issuance of the type rating.) The time in the make and model to be flown may be reduced to 10 hours provided the pilot holds an initial attack rating and completes training in maneuvers simulating Airtanker operations.

  2. Pilots who have flown as Co-Pilots in multi-engine Airtanker operations may count 50 percent of that time toward the 100 hours Pilot-in-Command requirement (left seat) to a maximum of 50 hours.

  3. or, performed as Airtanker Pilot (AKP) during the preceding 12 months.

  4. Initial Attack Training Pilots may perform the make and model experience requirements from either the left and/or right seat. Dropping loads of water for the Initial Pilot Inspector shall be demonstrated from both the left and right seat, with a minimum of two full loads total dropped.

Co-Pilot (AKC) shall possess:

  • FAA multi-engine rating.
  • FAA instrument rating-airplane.
  • FAA Commercial Certificate.
  • Class II Medical Certificate valid through the contract mandatory, pre-season, and post-season periods.
  • A current Forest Service or OAS Agency Pilot Qualification Record Card issued by a USDA/USDI approved Inspector of Pilots.
  • Meet the requirements of Federal Aviation Regulation Part 61.55 and 61.56.
  • The following flight experience:

- Pilot-in-Command-airplane

800 hours

- Flight hours the preceding 12 months-airplane

100 hours 1


  1. or, performed as an airtanker Co-Pilot/Pilot in the past 36 months and accumulated 100 hours of Pilot/Co-Pilot time on firefighting missions and documented observation of that performance by a designated Pilot Inspector, or received a Type rating in the make and model to be flown in the past 12 months.

Pilot's Handbook
Glossary of Fire Bombing Terms

Abort: Used to cancel an intended manoeuvre.

Accuracy: An assessment of the drop by the birddog.

Aerial Detection: A system for, or the act of discovering, locating and reporting wildfires from aircraft.

Aerial Ignition: The ignition of fuels by dropping incendiary devices or materials from aircraft.

Air Attack Officer: The person responsible for directing, co-ordinating and supervising a fire suppression operation involving the use of aircraft to deliver retardants, suppressants or firefighting forces to or on a fire.

Airtanker: A fixed wing aircraft fitted with tanks and equipment for dropping suppressants or retardants on fire. Airtanker groups are a provincial resource.

Armed: A confirmation by the tanker pilot that the drop system is set to allow immediate release of the load or any part thereof as previously requested by the birddog.

Birddog Aircraft: An aircraft carrying the person (Air Attack Officer) directing fire bombing action on a fire. Also referred to as the birddog.

Bombs Away "Now": A voice signal from the birddog on a dummy run to indicate trigger location.

Break Left or Break Right: A command for an immediate turn left or right.

Bulls-eye: An assessment that the drop was placed exactly where requested.

Calculated Manning Level: Manning level for the current day as determined by a calculation of the fire danger indexes and application of the appropriate Manning Level table.

Called Shot: A drop technique whereby the birddog triggers the drop by voice signal to the tanker (e.g., "Ready, 3, 2, 1, ... now").

Canadian Forest Fire Behaviour Prediction (FBP) System: A subsystem of the Canadian Forest Fire Danger Rating System. The FBP System provides quantitative outputs of selected fire behaviour characteristics for certain major Canadian fuel types and topographic situations.

Canadian Forest Fire Danger Rating System (CFFDRS): The national system of rating fire danger in Canada. The CFFDRS includes all guides to the evaluation of fire danger and the prediction of fire behaviour such as the Canadian Forest Fire Weather Index System and Canadian Forest Fire Behaviour Prediction System.

Canadian Forest Fire Weather Index (FWI) System: A subsystem of the Canadian Forest Fire Danger Rating System. The components of the FWI System provide numerical ratings of relative fire potential in a standard fuel type (i.e., a mature pine stand) on level terrain, based solely on consecutive observations of four fire weather elements measured daily at noon (1200 hours local standard time or 1300 hours daylight savings time) at a suitable fire weather station; the elements are dry-bulb temperature, relative humidity, wind speed and precipitation.

The FWI System consists of six components. The first three are fuel moisture codes that follow daily changes in the moisture contents of three classes of forest fuel; higher values represent lower moisture contents and hence greater flammability. The final three components are fire behaviour indices representing rate of spread, amount of available fuel, and fire intensity; their values increase as fire weather severity worsens. The six standard codes and indexes of the FWI System are:

  • Fine Fuel Moisture Code (FFMC): A numerical rating of the moisture content of litter and other cured fine fuels. This code indicates the relative ease of ignition and flammability of fine fuel.
  • Duff Moisture Code (DMC): A numerical rating of the average moisture content of loosely compacted organic layers of moderate depth. This code indicates fuel consumption in moderate duff layers and medium-sized woody material.
  • Drought Code (DC): A numerical rating of the average moisture content of deep, compact, organic layers. This code indicates seasonal drought effects on forest fuels, and the amount of smouldering in deep duff layers and large logs.
  • Initial Spread Index (ISI): A numerical rating of the expected rate of fire spread. It combines the effects of wind and FFMC on rate of spread but excludes the influence of variable quantities of fuel.
  • Build-up Index (BUI): A numerical rating of the total amount of fuel available for combustion that combines DMC and DC.
  • Fire Weather Index (FWI): A numerical rating of fire intensity that combines ISI and BUI. It is suitable as a general index of fire danger throughout the forested areas of Canada.
Canopy: The stratum containing the crowns of the tallest vegetation present (living or dead), usually above 20 feet.

Cardinal Points: The four chief points of the compass: North, South, East, West.

Chief: The ICS title for individuals responsible for command of functional sections: Operations, Planning, Logistics, and Finance/Administration.

Chock to Chock: Wheels roll to wheels stop

Clock Method: A means of establishing a target or point by reference to clock directions where the nose of the aircraft is 12 o'clock, moving clockwise to the tail at 6 o'clock, e.g., "The target is now at your 9 o'clock position".

Command: The act of directing, ordering, and/or controlling resources by virtue of explicit legal agency or delegated authority. May also refer to the Incident commander.

Command Staff: Consists of the information officer, safety officer, and liaison officer, who report directly to the Incident Commander.

Communications Unit: An organizational unit in the Logistics Section responsible for providing communications services at an incident.

Control a Fire: To complete a control line around a fire, any spot fires therefrom, and any interior island(s) to be saved; burning out any unburned areas adjacent to the fire side of the control lines; burn off any unwanted island(s) inside the control lines; and cooling down all hot spots that are immediate threats to the control line until the lines can be expected to hold under unforeseeable conditions. Stages of control are:

  • Out of Control: Describes a wildfire not responding or only responding on a limited basis to suppression action such that perimeter spread is not being contained.
  • Being Held: Indicates that with currently committed resources, sufficient suppression action had been taken that the fire is not likely to spread beyond existent or predetermined boundaries under prevailing and forecasted conditions.
  • Being Observed: Currently not receiving suppression action, due to agency resource management objectives and/or priorities.
  • Under Control: Having received sufficient suppression action to ensure no further spread of the fire.
  • Being Patrolled: In a state of mop-up, being walked over and checked.
  • Out: Having been extinguished.

Coverage Level: A number representing the number of gallons of retardant mixture dropped, or prescribed, to cover fuels in a 100 square foot area.

Crew: A temporary crew consisting of three squads placed in high fire danger areas where new ignitions may pose control difficulties at initial attack.

Day Basing: A procedure whereby initial attack resources are positioned away from their regular administrative or operational base for a burning period, in anticipation and readiness for fires that may start in a given area.

Deputy: Qualified individuals capable to act as a relief in the absence of a superior.

Director: The ICS title for individuals responsible for supervision of a Branch.

Divert: Change in aircraft assignment from one target to another or to a new incident.

Documentation Unit: Functional unit within the Planning Section responsible for collecting, recording, and safeguarding all documents relevant to the incident.

Door Interval: Time delay between doors for any drop sequence.

Door Length: Distance actually covered by a single door of retardant on the ground.

Double Door: A technique whereby two doors are opened simultaneously.

Drift: Advice or indication that a wind condition exists of sufficient velocity to significantly affect drop placement and that a correction factor must be allowed for.

Drop Height: Height of the tanker at load release, usually given in feet above tree top level.

Drop Sequence: The order and method in which the doors are opened.

Drop Zone: The area around and immediately above the target area for the release of the airtanker's load.

Dummy Run: A simulated bombing run made on a target by the birddog to indicate target and run to the tanker.

Early: Advice that the drop is to be or was triggered short of a designated point.

Elapsed Time: The difference in time between the beginning of an action and its actual accomplishment; in firefighting operations it is customarily divided into:

  • Discovery Time: The period from start of a fire (estimated or known) until the time of discovery.
  • Report Time: The period from discovery of a fire until the first person charged with initiating suppression action is notified of its existence and location.
  • Getaway Time: The period from receipt of report of a fire by the first person responsible for suppression until departure of the initial attack force.
  • Travel Time: The period between departure of the initial attack force for a fire and its arrival at the fire.
  • Attack Time: The period from receipt of first report of a fire to start of actual firefighting; includes both getaway time and travel time.
  • Control Time: The period from initial attack time until the fire is controlled.
  • Mop-up Time: The period from achievement of control until enough work has been done to ensure the fire cannot rekindle.
  • Patrol Time: The period from completion of mop-up until the fire is declared out.
Emergency Firefighting Crews (WFC Type III): Crews of 8 personnel, other than regular employees or pre-arranged suppression crews, hired on a casual basis expressly to fight fires.

Excursion: An unplanned but acceptable enlargement of the area intended to be treated with prescribed fire which does not greatly affect any off-sites values-at-risk and involves a minimum of suppression effort.

Extend: An instruction to tag on and extend the line and drop retardant in such a way that the load slightly overlaps and lengthens a previous drop, e.g., "Extend the last drop."

310-FIRE: The public can help detect and monitor forest fires by calling the 310-FIRE number to report forest fires to the Provincial Forest Fire Centre. This number should only be used to report a forest fire.

Fire Centre: This number should only be used to report a forest fire.

Final: A live bombing run where the tanker intends to make the drop.

Fire Behaviour: The manner in which fuel ignites, flame develops and fire spreads and exhibits other related phenomena as determined by the interaction of fuels, weather and topography. Some common terms used to describe fire behaviour include the following:

  • Smouldering: A fire burning without flame and barely spreading.
  • Creeping: A fire spreading slowly over the ground, generally with a low flame.
  • Running: A fire rapidly spreading and with a well-defined head.
  • Torch/Torching: A single tree or a small clump of trees is said to "torch" when its foliage ignites and flares up, usually from bottom to top.
  • Candling: A single tree ignites and flares up.
  • Spotting: A fire producing firebrands carried by the surface wind, a fire whirl, and/or convection column that fall beyond the main fire perimeter and result in spot fires.
  • Crowning: A fire ascending into the crowns of trees and spreading from crown to crown.
Fire Size Class: The assignment of a wildfire to a category according to its size (i.e., from the smallest fire to a very large fire). Recommended SI unit is hectares (ha). The following classification is used for reporting provincial wildfire statistics:
Letter Area (ha)
0.01 - 0.1
0.11 - 4.0
4.1 - 40.0
40.1 - 200.0
over 200

Flame Height: The average maximum vertical extension of flames at the fire front; occasional flashes that rise above the general level of flames are not considered. Recommended SI unit is metres (m).

Flanks: The parts of a fire's perimeter that are roughly parallel to the main direction of spread. The left flank is the left side as viewed from the base of the fire, looking toward the head.

FLIR: Forward Looking Infrared.

Forest Fire: Any wildfire or prescribed fire that is burning in forested areas, grass, or alpine/tundra vegetation. The main types of forest fire are:

  • Ground Fire: A fire that burns in the ground fuel layer.
  • Surface Fire: A fire that burns in the surface fuel layer, excluding the crowns of the trees, as either a head fire, flank fire or backfire.
  • Crown Fire: A fire that advances through the crown fuel layer, usually in conjunction with the surface fire. Crown fires can be classified according to the degree of dependence on the surface fire phase:
    • Intermittent Crown Fire: A fire in which trees discontinuously torch, but rate of spread is controlled by the surface fire phase.
    • Active Crown Fire: A fire that advances with a well-defined wall of flame extending from the ground surface to above the crown fuel layer. Probably most crown fires are of this class. Development of an active crown fire requires a substantial surface fire, and therefore the surface and crown phases spread as a linked unit.
    • Independent Crown Fire: A fire that advances in the crown fuel layer only.

The anatomical parts of a forest fire are:

  • Bay(s): A marked indentation(s) in the fire perimeter, usually located between two fingers.
  • Finger(s): An elongated burned area(s) projecting from the main body of the fire resulting in an irregular fire perimeter.
  • Flanks: Those portions of the fire perimeter that are between the head and back of the fire which are roughly parallel to the main direction of spread.
  • Head: That portion of the fire perimeter having the greatest rate of spread and frontal fire intensity which is generally on the downwind and/or upslope part of the fire.
  • Back: That portion of the fire perimeter opposite the head; the slowest spreading part of the fire.
  • Island(s): An area(s) of unburned fuels located within the fire perimeter.
  • Point(s) of Origin: The location(s) within the fire perimeter where ignition(s) first occurred.

Frontal Fire Intensity: The rate of heat energy release per unit time per unit length of fire front. Flame size is its main visual manifestation. Frontal fire intensity is a major determinant of certain fire effects and difficulty of control. The Fire Intensity Rank Chart is used to determine difficulty of control.

Gap: A weak or missed area in a retardant line.

General Staff: The group of incident management personnel reporting to the Incident Commander. They may have a deputy, as needed. Consists of the Logistics Section Chief, Operations Section Chief, Finance/Administration Chief, and the Planning Chief.

Global Positioning System: Employs a constellation of 24 high-orbiting satellites that provides (depending on the receiver used) three dimensional positioning (latitude, longitude, altitude), velocity, track, and time transfer information worldwide.

Group Support Unit: Functional unit within the Support Branch of the Logistics Section responsible for the fuelling, maintaining, and repairing of vehicles, and the transportation of personnel and supplies.

Half On/Half Off: A drop made parallel to a given reference with half the retardant covering the reference and half outside.

Head: The most rapidly spreading portion of a fire's perimeter, usually to the leeward or upslope.

Head End of Drop: The most forward end of the drop on the ground.

Helitack Crews (WFC Type I, formerly known as Initial Attack Crews): This Type I crew consists of three to eight-person crews based in districts across the province. These individuals undergo two weeks of rigorous and physically demanding training on safety practices and firefighting procedures. By getting to the scene quickly, these crews can control and extinguish fires at a small size.

Helitack Support Crews (WFC Type I-HS): These 8 man crews are designed to provide rapid support action for Rapattack and Helitack crews on new fire starts, and remain on the fire for up to 48 hours without resupply. These individuals undergo two weeks of rigorous and physically demanding training on safety practices and firefighting procedures.

High Wind Forecast: A wind forecast for 25 km/h or higher.

Hold: An instruction not to drop and to await further advice.

Hot Spot: Particularly active part of a fire.

Incident: An occurrence or event, either human caused or natural phenomena, that requires action by emergency service personnel to prevent or minimize loss of life or damage to property and /or natural resources.

Initial Attack: "Initial attack" is the term used to describe the initial steps taken to suppress wildfire using mobile fire suppression crews. There are five types of Wildland Firefighting Crews (WFC): Rapattack, Helitack, Helitack Support, Sustained Action, and Emergency Firefighter. The main differences between these crews are: their base locations, training requirements and crew size. Another initial attack tool used is the eight airtanker groups consisting of: one Douglas DC-6,two Convair CV580, one Air Tracker AT802, two CL215, and two Douglas B26 groups.

Inspection Run: A pass over the target by the tanker to assess the run as requested.

Island: Green or unburned area within the fire perimeter.

Knock Down: To reduce flame or heat in a specified target. Indicates the retardant load should fall directly on the burning perimeter or object. Used to assist ground forces.

Late: Advice that the drop is to be or was triggered beyond a designated point.

Lead-in: A technique whereby the tanker follows the birddog on a final run.

Live Run: A flight over the drop area in which a discharge of cargo or retardant/water, etc., will be made.

Load Width: Width actually covered by a drop on the ground.

Long: Assessment that the drop landed beyond a designated point.

Main Ridge: Prominent ridge line separating river or creek drainage. Usually has numerous smaller regions (spur ridges) extending outward from both sides. Can be confusing if not covered in orientation.

Minimum Rest Period: means a period during which a flight crew member is free from all duties, is not interrupted by the air operator or private operator, and is provided with an opportunity to obtain not less than eight consecutive hours of sleep in suitable accommodation, time to travel to and from that accommodation and time for personal hygiene and meals.

NOTAM: Notice to All Airmen - an official notice that describes airspace where no person shall operate aircraft, issued pursuant to the Canadian Air Regulation Standards.

Parallel Identification: A technique used to identify the target whereby the birddog and tanker fly parallel to each other.

Planning Section: Responsible for the collection, evaluation, and dissemination of tactical information information related to the incident and the preparation and documentation of the incident action plan. Includes the Situation, Resource, Documentation Units, as well as the Technical Specialists.

Preparedness: Condition or degree of being able and ready to cope with an anticipated fire situation.

Provincial Forest Fire Centre (PFFC): Alberta's PFFC headquarters is located in Edmonton. From the PFFC, the department monitors the forest fire situation, conduct audits on forest fire operations and provides technical assistance to the districts and regions across the province. Meteorologists in the department track weather patterns and calculate fire hazards with the latest computer technology. Other experts research the natural cycles of fire and predict where and when forest fires are likely to occur. Besides forest fires, the department also has specialists who help protect forests from disturbances caused by insects and disease.

Rapattack Crews (WFC Type I-R, formerly known as Helitack): One of Alberta's firefighting Type I crews is known as Rapattack-or Hotshot-crews. Alberta's specialized Rapattack program, one of only two in Canada, has been in existence for 19 years. These seven-person crews undergo a month of intensive rappel training including a physically demanding training course, emergency retrieval procedures and ongoing evaluations. Competition for positions on one of the 10 Rapattack crews is very competitive. These crews are Edmonton based and are transported to the field wherever the hazard dictates. To allow for quick response to remote areas of the province, these crews are transported to fires by eight contracted medium rotary-wing aircraft.

Reload: An instruction to the tanker to proceed to a designated location and reload.

Rising Ground: Indicates that the ground ahead or beside the target is higher than the target itself.

Roll Up: Connecting the head end of a drop to a given point.

Run: The flight path of the tanker to the target.

Saddle: Depression or pass in a ridgeline.

Safety Zone: An area used for escape in the event the fireline is overrun or outflanked, or in case a spot fire causes fuels outside the control line to render the fireline unsafe. During an emergency, tankers may be asked to create a safety zone using retardant drops.

Salvo: A technique whereby a specified number of doors are opened simultaneously.

Short: Assessment that the drop landed before a designated point.

Single Door Drop: A technique whereby only one door is opened.

Slop Over: The extension of a fire across a control line.

Snag: A standing dead tree or part of a dead tree from which at least the leaves and smaller branches have fallen. Often called a stub, if less than 20 feet tall.

Span: Refers to a distance equal to the wing span of the tanker being used.

Spot Fire: A fire caused by the transfer of burning material through the air into flammable material beyond the perimeter of the main fire.

Stay: An instruction to the tanker to proceed to a designated location and await further instruction.

String Drop: A technique whereby a specified number of doors are opened in succession to give an extended pattern on the ground.

Surface Fire: Fire that burns surface litter, other loose debris of the forest floor, and small vegetation.

Sustained Action Crews (WFC Type II): These crews are either contract or seasonal wage. They consist of eight personnel who also undergo two weeks of vigorous and physically demanding training on safety and firefighting procedures, including options in forest management practices. These crews may help other programs, i.e., industry, when fire hazard permits.

Tag On (and Extend): To drop retardant in such a way that the load slightly overlaps and lengthens a previous drop; e.g., "Extend the last drop."

Tail End of the Drop: The aft end of the drop on the ground.

Target Elevation: The elevation in feet of the dummy run at the target. Allows the tanker to set up the final run.

Technical Specialist: Personnel with special skills who are activated when needed i.e. fire behaviour annalists.

Tie-in: To connect a retardant drop with a specified point: road, stream, previous drop, etc., e.g.,"Tie-in tanker 62's drop with the road."

Today's Actual 500 mb Anomaly: The difference between today's 500 mb height and the average 500 mb height for today. Expressed as a number such as +8, 0, -5, etc.

Today's Forecast 500 mb Anomaly: The prediction of tomorrow's 500 mb anomaly.

Traffic Pattern: The path or route aircraft traffic takes when landing or taking off or when performing tactical missions in the airspace or operations area over a fire.

  • Base: A flight path at right angles to the landing runway or target off its approach end.
  • Crosswind: A flight path at the right angle to the landing runway or target off its upwind end.
  • Downwind: A flight path parallel to the landing runway or target in a direction opposite to landing or drop area.
  • Final: A flight path in the direction of a landing or drop.
  • Upwind: A flight path parallel to the direction of the final before turning crosswind. NOTE: Used with the term "Turning".
Trail Drop: A technique whereby the flow of retardant from the aircraft is restricted so as to give a long unbroken line.

Trend Forecast: The weather forecaster's interpretation of how tomorrow's fire weather conditions will compare with today's.

Upper Ridge: A meteorological term referring to an elongated area of relatively high atmospheric pressure in the upper atmosphere, usually associated with an increase in fire weather severity at the earth's surface.

Upper Ridge Breakdown: A weakening or collapse of an upper ridge which is generally associated with an increase in fire weather severity at the earth's surface with multiple ignitions from lightning often occurring. Determination of an upper ridge breakdown will be the weather forecaster's responsibility.

Wildland Firefighting Crew (WFC): is the Forest Protection Division basic firefighter crewit consisting of 6 firefighters, one leader and one subleader.

Wingspan: The length of a wing span from tip to tip. Used to make low level flight route adjustments, e.g., "Move your drop one wingspan to the right."




Parts of a fire
A fire will have the following parts to help clarify each area of the fire. Air units often use these terminologies since they can see the fire from an aerial point of view. The Head of the fire is the most active portion of the fire and shows where the direction of the fire is heading. This is also where the most active attack on the fire takes place. The heel is the complete opposite end of the head. There is usually very little fire activity here since the wind is not pushing the fire into unburnt areas. The origin of the fire is usually near the heel. A finger is a small area of the fire that is protruding from the main part of the fire. Sometimes a finger is an old head before the winds shifted and the head went elsewhere. The green is anything that is unburned outside of the fire.


As a tanker drops from orbit it usually travels "downwind" and takes a close look at the drop "target". Then it circles on "base" and turns "final" in order to drop its load on the head or the flanks of the fire. After it drops it might stay and do another drop, go back into orbit, or head directly to the base for a refueling.


Air Attack ship orbits high above the fire and is usually the first on scene unless a helicopter gets in there first. Air Attack will set up in a high orbit and radio in his/her observations on the fire to the ground units. Then as the tankers start coming in they will be placed in an orbit OPPOSITE of the air attack orbit away from the plume of smoke for safety reasons. They fly opposite orbits so Air Attack sees the planes twice as much. There is a designated direction for both but I can't recall which is what. One by one as air attack directs them a tanker will drop from that orbit into a lower orbit and drop it's load on the fire from that orbit. Then it will go back up to the higher orbit and back to the tanker base for reloading. Meanwhile the helicopters are skipping low along the ground between a water source (called the "pond" on a fire) and the fire's edges and hot spots. If the fire isn't big enough, then tankers and copters can;t fight the fire at the same time. If there is one copter, it is easy while the tanker drops the copter loads and while the copter drops the tankers orbit. They stay out of each other's way.

On a bigger fire with plenty of tankers and helicopters the two may be fighting totally seperate lines of the fire and not have to worry about each other. This diagram shows the cross section of the orbits and how everybody stays out of the way. Next time you are on a fire look up and watch them all circle around at different elevations. And over the radio, using this diagram will help you visualize what you are hearing as everybody talks away.


Drop testing air tankers


An average of 15.8 million gallons of fire retardant has been used in firefighting each year. Most of this retardant is released from the air. Aircraft are used to transport firefighting chemicals at the appropriate height and speed. The types of aircraft include:

  • Fixed-wing multiengine airtankers.
  • Fixed-wing single-engine airtankers.
  • Helicopters with fixed tanks.
  • Helicopters with suspended helibuckets.

The fire-retarding chemicals typically used in wildland firefighting are short-term and long-term retardants, foam, and water. The retardants may include a gum thickener.

The 10 principles for proper retardant application are:

An average of 15.8 million gallons of fire retardant has been used in firefighting each year. Most of this retardant is released from the air. Aircraft are used to transport firefighting chemicals at the appropriate height and speed. The types of aircraft include:

  • Fixed-wing multiengine airtankers.
  • Fixed-wing single-engine airtankers.
  • Helicopters with fixed tanks.
  • Helicopters with suspended helibuckets.

The fire-retarding chemicals typically used in wildland firefighting are short-term and long-term retardants, foam, and water. The retardants may include a gum thickener.

The 10 principles for proper retardant application are:

  • Drop height and drop speed.
  • Flow rate of the liquid as it exits the tank.
  • Volume of the liquid released.
  • Tank geometry and venting.
  • Gating system (the tank doors and release mechanism installed in an aircraft to release retardant).
  • Rheological properties of the fire chemical (the flow characteristics of a fluid).
  • Wind speed and direction.
  • Temperature and relative humidity.
  • Fuel type.
  • Topography.
  • Safety concerns of aircraft and ground personnel.
  • Pilot proficiency.

Since the 1950’s the Forest Service has used a procedure known as drop testing to quantify ground patterns. The procedure involves dropping fire chemicals from an airtanker flying over open cups arranged in a regularly spaced grid (figure 2). The cups are weighed before and after the drop to calculate the amount of retardant deposited in gallons per hundred square feet (gpc). These values are plotted onto a map of the grid. Points between cups are estimated, usually by an interpolation method that assumes uniform change between cups. Contour lines are made by connecting all points of equal coverage level. The length of each contour, referred to as line length, is calculated from observed and estimated data.

During a drop test, drops are made at varying drop heights, drop speeds, flow rates, volumes, and with different retardant materials to obtain a graphical and numerical picture of the ground patterns produced by the airtanker. Examining ground patterns provides information about the factors that influence the distribution of the drop.

Some factors in a drop can be controlled, such as height, speed, flow rate, tank and gating system, and rheological (flow) properties of the retardant. Wind speed, wind direction, temperature, humidity, fuel type, and topography are among the factors affecting the ground patterns that cannot be controlled (Newstead and Lieskovsky 1985). Drop tests allow different tank and gating systems to be compared under similar conditions. Ground patterns can help managers learn the capabilities of an airtanker by determining the intervals between trail drops (figure 4). A trail drop is when door opening times are staggered to produce a long stream of retardant. An accurate set of ground patterns from an airtanker provides data to predict the time between releases needed for a successful trail drop.

Mechanics of the Release

As an airtanker releases a load of retardant, the fluid is distributed along the flight path. The characteristics of the drop (length, width, and coverage level) are a function of the height and speed of the aircraft, the flow rate and volume of the fluid exiting the tank, the rheological properties of the fluid, and the meteorological conditions.

The design of the tank and gating system directly affects the retardant flow rate. Relevant design elements include the size and shape of the door, the speed with which the door opens, and the geometry of the tank vents, baffling, cylinders, torque tubes, and other items inside the tank. We have relied on the cup-and-grid method to understand how these factors influence the ground pattern