A Canadair doesn't put out a wildfire. It slows a fire head so crews on the ground can hold it. A wildfire is won on the ground, with hoses, shovels and bulldozers, often at night.
The French doctrine: hit fast
France's strategy rests on the massive attack on new fires: during the risk season, resources are pre-positioned and aircraft patrol loaded with water, to hit every new fire within minutes. The vast majority of fires are stopped this way before they cover a single hectare. A fire that escapes that first attack, on the other hand, can last for days.
Who responds
- Firefighters from the departmental fire services, in wildland fire tenders, grouped into columns.
- Civil Security military units, specialised in large fires and reinforcements.
- Foresters, who know the ground, the tracks and the water points.
- Air assets: Canadairs, which scoop about 6 tonnes of water in a dozen seconds skimming the sea or a lake, Dash 8 aircraft, which drop a red retardant, and water-bombing helicopters.
Direct attack
When the fire is still small or calm, it's attacked on its edge, where the flames meet the vegetation: water from hoses, fire beaters, shovels, thrown earth. Always starting from a safe point, a road, a rock, an already burned area, called the anchor point, and working up the flanks towards the head. A violent fire head is never attacked from the front.
Indirect attack
When the fire is too strong, crews work ahead of it, at a distance:
- The control line: a strip where all fuel is removed down to bare soil, by bulldozer or hand tools, tied into a road or track.
- Retardant dropped from the air: a product based on ammonium salts that soaks the vegetation and slows burning, even after the water has evaporated.
- Tactical fire, or backfire: deliberately lighting, from a control line, a fire that burns the vegetation towards the wildfire. When the front arrives, it finds nothing left to burn. A powerful and dangerous technique, reserved for trained personnel and precise wind conditions.
Night and mop-up
- At night the fire calms down: the air cools and grows damper, the wind often drops. That's when ground crews gain the most ground, while aircraft aren't flying.
- A contained fire isn't out. The edge must be mopped up: digging, turning, soaking every stump and root that smokes, tens of metres inside the burned area. A poorly mopped-up fire restarts the next day with the afternoon wind.
Crew safety
Wildland firefighters all over the world apply the same rule, summed up in the United States by the acronym LACES:
- Lookouts: people watching how the fire develops;
- Anchor points: a safe anchor;
- Communications: a radio that works;
- Escape routes: escape routes scouted in advance;
- Safety zones: safe areas to shelter in, often an already burned area.
The oldest rule of ground crews fits in one image: keep one foot in the black, meaning stay at the edge of the already burned area, where the fire can't come back.
What the old hands know
- Fire changes in the early afternoon: the hottest, driest, often windiest hour. Many tragedies happen between 2 and 5 pm.
- A sudden lull is suspicious: the wind can shift and turn a quiet flank into a fire head.
- Narrow gullies, steep ravines and saddles act like chimneys: fire speeds up violently there. Never go into one above a fire.
- Aircraft don't fly at night or in thick smoke, and wind that's too strong grounds them: the most dangerous days are often the ones where they help least.
For the phenomenon itself: Wildfires. For what a private person can do: Wildfire, defending yourself and getting out.