Elk Complex Helicopter Accident (California) – July 23, 2007

This Day in History is a brief summary of a powerful learning opportunity and is not intended to second guess or be judgmental of decisions and actions. Put yourself in the following situation as if you do not know the outcome. What are the conditions? What are you thinking? What are YOU doing?

Incident Summary:

A handcrew was assigned to mop up on the Elk Complex. The crew’s superintendent requested blivets through the Division Supervisor (DIVS) to support the operation. A medium helicopter would deliver the blivets by longline.

Two days before the accident: The DIVS anchors a fluorescent panel to the ground (used for indicating landing and drop zones) for the handcrew to use. The terrain in the area consisted of steep slopes and trees from 75 to 200 feet tall.

Day before the accident: The crew prepared for blivet delivery. The location of the panel remained as placed by the DIVS. The helicopter made the blivet drop close to the panel. The crew member who is marshaling warns the pilot about the proximity of one tree located to the right and upslope of the panel. Concerned with their own safety, two ground crew members distance themselves from the blivet drop site. The division safety officer visited the site after the blivet delivery. There was no discussion regarding the drop zone location or recognized hazards.  At the After Action Review (AAR) in camp that evening, there was no mention of it. Additional blivets and backhaul were requested by the crew superintendent through the DIVS for the following day.

Day of the accident: The pilot was informed that he would be delivering more blivets to the same drop zone. Two crew members, not on site the previous day, staff the drop site. The panel remained in the same location as the previous day. Though the helicopter was equipped with a 150 foot longline, the marshaller communicates with the DIVS that a longer longline is recommended. By the time the recommendation was transmitted to the helibase, the helicopter was en route with blivets. Due to radio traffic, the marshaller and pilot did not communicate until the helicopter was on final approach to the drop site. Crew members witness the helicopter drift to the right as the blivets are set down and the main rotor strike the tall tree. The longline and the blivets remain attached as the helicopter turns left and flies downhill, impacting trees as it falls to the ground. The helicopter was destroyed. Though crew members provide assistance, the pilot was killed.

Discussion Points:

Lookouts – In medium helicopters many pilots fly external load missions from the left seat, leaning left out the bubble window. This decreases the pilot’s ability to see to the right of the aircraft. As ground personnel working with helicopters, you may have a view of hazards that the pilot does not.  

• If you are giving a new pilot a briefing about hazards in your area, what will your emphasis points be?

Communications – During a post-accident interview, two crew members stated that they were so concerned about the potential for an accident that they briefed each other three times on what action would be taken in the event of an accident.

• Discuss some of the reasons that people do not speak up when they see something wrong.
• During your work today, you may only get one chance to communicate a hazard before an accident happens. Identify how you and your crew will combat the reluctance to verbalize hazards.

There was a wider open spot a short way down the line that would have made a better drop site, but the DIVS had placed the panel in a convenient spot for the crews and did not communicate that he did not intend it to be the drop site for the blivets.

• Discuss how your crew leader wants crew members to speak up with questions, ideas, and solutions.

Escape Routes – We strive to work as safe as possible, but when things go wrong we need a way out. Just as with fire and felling, pilots in aircraft and the ground crews working with them need to establish escape routes for the aircraft and the ground crew.

Safety Circle - The helicopter's main rotor impacted the top 15 feet of a 165-foot tree. This means the helicopter’s safety circle was not big enough to remain clear of hazards (A safety circle is generally recognized as 1½ times the rotor diameter and is used for keeping a safe distance from hazards both on the ground and in-flight).

• Using your Incident Response Pocket Guide (IRPG) PMS 461, identify the minimum size of a safety circle for a medium helicopter.
• What are some ways to estimate the height of a tree?
• What are some options you have as a ground crew to improve a drop site with a hazardous tree?
• What are some options you have as a ground crew if you have an unsafe condition at the drop site and the helicopter is en route?
• What immediate actions do you take as a ground crew at a drop site if the helicopter is getting too close to a hazard?
• Could asking the pilot to do a recon of the drop site have potentially changed the outcome of this accident?