I remember a comment my instructor made during flight school for ultralights: “Are you ahead of the aircraft or behind it?” Obviously, the key is to be ahead of the aircraft, where you are in control and anticipating what will happen next. Once the situation turns around and you are behind the plane and reacting, you’re in trouble.

Many aviation incidents are the result of an inappropriate response to unexpected events. These are often loss of control (LOC) incidents, where there is an unintended departure of the aircraft from controlled flight. For example, the aircraft departs from its normal flight envelope and stalls. The pilot is unable to regain control of the aircraft. The pilot is not ahead of the plane but instead is behind, reacting to its movements rather than anticipating them.

We also can have LOC incidents during arboricultural operations. You are either in control of the tree or it is in control of you. The dismantling job starts out just fine, everything seems to be going as planned, but then the climber notices a conk (fruiting body to a fungus) on the limb holding the block and expresses a concern that the limb might not support the rigging load. The comment is ignored by a distracted crew leader dealing with the customer, so the climber shrugs and starts the saw. The crew should have noticed the conk during the pre-work inspection, but the inspection wasn’t done till the climber was already in the tree.

The new crew member tending the lowering device is standing beneath the tree holding the line, not knowing what to do because no one explained how to lower a limb or operate the device. The crew member who is supposed to be responsible for the operation is busy replacing a chain that another worker had dug into the dirt while cutting up some logs. This crew member figures he has time, since the climber is supposed to be setting up the rigging rather than starting to cut so soon.

The climber neglects to communicate that he is cutting the limb now – since it makes him nervous and he wants to get it over with. The only warning the new worker has is that the line to the lowering device suddenly goes taut. The limb cracks under the load and swings toward the climber as the startled ground crew runs to escape the falling debris. Now everyone is reacting to the tree – not leading it.

Undetected errors can lead to critical failures that become incidents. What leads to these incidents? Usually one or more of these factors:

• Interruptions and distractions – The crew leader is talking to the customer, and a crew member is having to replace a chain.

• Tasks taken out of sequence – The job briefing was delayed until the climber was already aloft, and no one considered aerial hazards, instead focusing on hazards they deal with on the ground.

• Unanticipated tasks – The new ground member did not know the limb was being cut when it was, and the crew leader had not expected to be talking to the customer.

• Interweaving of multiple tasks – A common theme to many incidents is information overload; a discussion with the customer, replacing a nicked chain and cutting a limb all were occurring simultaneously rather than everyone focusing on the one critical task – safely lowering the limb.

A contributing factor in this scenario was communication failure; all people involved were in their own little bubble, which is a challenge that aviation had to address. If you are the pilot and only passenger, it’s all on you. However, if you are sharing responsibilities, it’s essential that both the captain and first officer each clearly understands their duties and responsibilities. The challenge in aviation was that the captain was the authority; the captain’s commands were not to be questioned, but followed.

This rigid hierarchy was considered a factor in many aviation incidents. Communication failure was the primary contributing factor in more than three-quarters of the root-cause analysis of aviation incidents. Incidents occurred when the co-pilot or flight engineer was aware of an error but was unwilling or unable to alert the captain. One incident involved the captain focusing on a landing-gear problem for an hour and ignoring the flight engineer’s warning that their fuel was critically low. The plane ran out of fuel on its final approach and crashed short of the runway, killing 10 passengers aboard.

Crew resource management (CRM) was the outcome of the analysis of these incidents. The idea was to create a less-restrictive environment where first officers could question captains if they observed conditions that might lead to errors. The captain was still the captain and the hierarchy of command was maintained, but respectfully questioning authority was permissible and desirable.

The objectives of CRM are to overcome communication issues, improve decision-making and define leadership responsibilities among others. The goal is to empower the team members to use all their skills and knowledge to effectively and safely perform their duties. This approach went beyond just the captain and first officer to include all flight personnel. It now has expanded to other professions where human errors can have fatal outcomes, such as emergency medical services.

Arboriculture shares few similarities to aviation other than they both are high risk (pilots and flight crews have a higher fatality rate than arborists). But we also are guilty of having a rigid hierarchy – one crew leader and everyone else is the crew. Too often the crew leader’s instructions are followed despite misgivings by the crew.

We had one incident when a crew member was told by the crew leader to fell a tree into an adjacent dead tree so both would fall, a risky procedure and one that should not be attempted. However, the crew leader was the boss, so the crew member cut the live tree to fall into the other tree. As the saw operator stepped back along his retreat path, he was fatally struck by a dead limb that snapped off the dead tree on impact with the felled tree.

In another instance, the crew leader stepped up on the in-feed table to clear a jam in the chipper. He told his crew to stand back, they weren’t supposed to do this, but he would jump up there and kick the jam free. Instead, his foot caught and he was pulled completely through the chipper. Obviously, standing on the in-feed table is a violation of safety regulations and common sense, but the crew just stood by and watched.

Operating in any high-risk environment requires a highly functional team, as the cost of errors is high. Tree care companies would be wise to consider the CRM approach to team management.

Five key components to CRM

1. Mission planning

The first step – plan the work and ensure all members of the team know their roles and responsibilities. This is part of the all-important (and frequently ignored) prework inspection and job briefing required for arboricultural operations. These are the keys to a safe and efficient operation, and these are common among many other occupations where the outcome of errors can be fatal.

During the ultralight flight school (all of 15 hours with another 15 of dual flight), they taught us that the importance of a thorough pre-flight cannot be overemphasized. The pre-flight procedure is performed systematically, never varied, and done with the co-pilot (unless flying solo).

According to the ANSI Z133 Safety Requirements for Arboricultural Operations, section 3.4.3, a job briefing shall be performed by the qualified arborist in charge before the start of each job. While the crew leader is responsible for the briefing, that does not mean it has to be read as a litany. That’s a good way for crew members to become bored and distracted. Instead, the crew leader can call on crew members to lead it or to lead one of the subjects required to be covered in the job briefing: hazards associated with the job, electrical hazards, personal protective equipment, job assignments and work procedures. After all, arboriculture is a team effort and everyone, not just the leader, should know the job, not just their tasks. If you know the work procedure, you are more likely to be aware when the situation changes.

2. Maximizing situational awareness

Situational awareness involves being constantly aware of the surroundings and alert to any unanticipated changes. Everyone on the team must maintain an awareness of the entire operation as it unfolds, not just their present task, recognizing when conditions change beyond planning and determining whether these changes require corrective action. But this requires communication among the team members.

3. Clear communication

Clear communication goes beyond having a communication protocol, for example, our command-and-response system. Every team member must be empowered to communicate any concerns at any point during the operation as well as voice corrections or clarifications. While there must be a defined leader, all voices should be equal, and everyone has the responsibility to identify potential errors and come up with solutions.

When workers are told to shut up and go back to work, rather than allowed to voice a concern, the team is in trouble. The last comment you want to hear from someone is, “That’s not my job.” Safety is everyone’s job, and it starts with teamwork.

4. Improved teamwork

Teamwork begins with training on the protocols and operating procedures. Everyone must learn to interact. A key is the understanding that all humans, which is everyone on the team, including the leader, make mistakes. In the Swiss-cheese model of process safety (figure at left), incidents occur only when the errors (holes in the Swiss cheese) line up through the multiple layers of cheese. A means of reducing failures due to human error is to insert additional layers of cheese – every crew member who is working as part of the team becomes a layer. It does not matter if you are the climber or a ground pounder, you are equally important in detecting errors.

5. Effective decision-making

Team members continually evaluate the situation, staying focused on what is occurring and anticipating possible corrections and consequences. This is really the culmination of the previous four points.

“To err is human” goes part of the phrase by Alexander Pope. Humans, even crew leaders, make errors. But we want errors not to evolve into failures and incidents. The key purpose of CRM is management of human errors, and that is best accomplished as a team working together to efficiently and safely perform the job. Remember, you are as safe as your least-trained worker; everyone has an equal responsibility for the safety of the team.

John Ball, Ph.D., BCMA, CTSP, A-NREMT (National Registry of Emergency Medical Technicians), is professor of forestry at South Dakota State University and a Board Certified Master Arborist.