Helicopters, Controlled Burn, and Crew Management
How Helicopters Influence Land Conservation and Restoration
Hiking through the forest, you hear the distinct thump of a Bell 205 in the far distance. Beyond the forest wall, you see the helicopter flying just above the treetops and
notice it’s dropping something that resembles ping pong balls from its belly. What is that?
It’s a prescribed fire being conducted by aerial ignition crew members from a helicopter.
Controlled burning has deep Southern historical roots, dating back to Native Americans. Its primary focus was to improve forage conditions for wildlife in traditional hunting grounds, clear land for settlements, and control overgrown understory vegetation.
It wasn’t until the 1970’s that the public and foresters accepted the benefits of applying fire to the landscape on public lands. By then, there were 50 years of studies and historical information in the southern US and- many more years of practical experience by landowners that carried on the Native American tradition of burning the landscape- to influence land managers on the benefits of prescribed fire to support restoration and maintenance of certain natural communities.
Fast forward to the present where “mega fires” scorch millions of acres, devastate communities, and disrupt everyday life for millions of people annually.
Prescribed burning is essential to maintaining balanced ecosystems for forest health, as well as wildfire prevention.
Trees, grass, leaves, brush, pine needles are all considered “fuel.” With approximately 1.83 billion undeveloped acres in the continental United States alone, it’s impossible to stay ahead of managing that much land by foot or vehicle.
Wildland firefighters on the ground carry drip torches filled with gasoline and diesel that spurt a line of fire behind them as they tread the forest floor, leaving a slower-paced blaze behind them. To speed up the process and treat acres economically, land managers frequently utilize helicopters and (more recently) drones to ignite prescribed fires within a “burn unit.”
The main distinction of prescribed fire application is that land managers choose to proactively burn when environmental conditions are favorable for achieving forest management goals, while also being able to control the burn more easily as opposed to the reactive nature of wildfire suppression during the dry summer months.
To perform aerial ignition from aircraft, it’s a fairly simple process, albeit with added risk to flight crews, balancing the risk versus reward tradeoff. Mission planning is often started weeks in advance to ensure that the aerial ignition machines mounted in the aircraft are functioning properly, since there is the risk of having an onboard fire in the aircraft.
Helicopter crew members and pilots must attend annual refresher training for aerial ignition which covers normal operating procedures, specialized communication within the aircraft, emergency procedures in the event of a “hang fire” in the ignition device, emergency egress/Crash Rescue procedures, secondary restraint training, and discussion on the flight mission profile (typically <60 knots and <300’ AGL, i.e., “low and slow.”)
The “ping pong balls'' are filled with potassium permanganate. These are then injected with ethylene glycol (antifreeze) by the Plastic Sphere Dispenser (aerial ignition machine) to create a chemical reaction which combusts approximately 20-30 seconds after injection. The spheres are then dispensed down a chute between the fuselage and skids of the helicopter, on the rear-right side of the helicopter.
As we all know, the rotors on a helicopter don’t allow it to glide very well when there is a loss of power- to perform a successful autorotation, speed and altitude are needed. Those two items are essentially stripped away for the mission of aerial prescribed burning in a helicopter and all crew members onboard are in the “dead man’s curve,” flying low and slow for hours on end. Dropping the spheres too high will result in drift and increase the chances of starting an uncontrolled spot fire outside of the designated burn unit. There is also some technique and skill required for the route the PIC will take while lighting these controlled fires.
Without getting too nerdy on fire tactics and ecology – in short - the PIC must maintain a certain speed and route to have a successful prescribed burn and the victory of the entire operation is dependent on them flying low and slow in designated lanes.
Wind, terrain, weather, and smoke are all evaluated constantly during live operations. Task saturation is prevalent between in-cabin machine commands, air-to-ground communications, and general Crew Resource Management (CRM) communication. The pilot is looking down through the bubble, the convex mirror, up at the terrain, flipping radio frequencies buttons, watching their GPS, constantly communicating with the ignition specialist in the SIC seat, and scanning the horizon for additional hazards and aircraft that may have entered the air space.
The crew member in the back is working in small quarters with the machine taking most of their leg room, communicating with their head down to ensure that the machine is functioning properly, and ensuring that operations are executed as directed. The crew member in the SIC seat is head down, up, around and communicating to ground forces and in cabin desired helicopter routes. There are few moments of a sterile cockpit and getting a word in for potential hazards happens abruptly.
If you read my last blog post “ Assessing Risk In Chaos “ then you will notice a common thread on the importance of CRM in this industry. Having a robust Safety Management System (SMS), combined with effective CRM involve the proactive method to superior operational safety.
By having a culture that demonstrates safety and encourages everyone in an organization to think, behave, and act with safety in mind, we can begin to create a way to categorize hazards and manage risk effectively before, during, and after operations to increase safety. After all, it’s important to understand that 100% accident prevention in the aviation industry is not an attainable goal. What is an attainable goal is mining and monitoring data through SMS and participating in CRM that contributes to improving our margins of error in real-time.
No system design is flawless, and every system degrades over time. It takes all crew members proactively, and almost subconsciously, thinking and debriefing how they can continuously improve on each flight, each operation, each process.
One mission is to measure and assess how safe their mission was, how degraded the system may have become, and lessons learned /mitigations put forth to improve on what may be required for the next operation.