Learning From the Past
By Gene Trainor, FAA Compliance and Airworthiness Division
When it comes to aviation accidents, understanding past mistakes and recommended recovery actions is an important way to help prevent future accidents.
That is why the FAA has created a Lessons Learned from Civil Aviation Accidents Library at lessonslearned.faa.gov. The library contains information-rich modules from selected large airplane, small airplane, and rotorcraft accidents.
A newly added lessons learned module is underway that covers a significant helicopter accident from 2015 that occurred in Frisco, Colo.
This accident stands out because it helped prompt watershed Congressional legislation requiring rotorcraft (helicopters and gyroplanes) manufactured on or after April 5, 2020, to contain crash-resistant fuel systems.
The Frisco Lessons Learned module helps pilots and mechanics learn about potential risks through an exhaustive description of an actual accident.
When it comes to aviation accidents, understanding the details from the past is an important way to help keep future accidents from occurring under similar circumstances or for similar reasons.
On July 3, 2015, at 1:39 p.m., an Airbus Helicopters Model AS350B3e helicopter lifted off from a hospital en route to a public relations event at a Boy Scout camp. Immediately after liftoff, the helicopter started spinning counterclockwise and then crashed into a recreational vehicle parked near the heliport. The pilot was killed and the two flight nurses were severely injured. A post-crash fire followed within seconds because of spilling fuel that ignited. One of the flight nurses exited the aircraft through the left-side door but suffered burns over 90% of his body. The other nurse was ejected from the helicopter upon its impact into the parking lot.
So how did this occur? As with many accidents, several factors combined to create a tragedy. In this case, the helicopter’s tail rotor flight control design and warning systems, the pilot’s pre-flight inspection, and the lack of a crash-resistant fuel system all played a role, according to the National Transportation Safety Board and FAA analysts who developed the Lessons Learned module.
The crash was among three similar events that prompted the FAA to issue two emergency airworthiness directives (EADs). The FAA EADs require actions to prevent Airbus Model AS350B3 helicopters from taking off without hydraulic pressure in the tail rotor hydraulic system. This loss of hydraulic pressure caused the Frisco helicopter to spin. The pilot conducted a pre-flight check of the tail rotor hydraulic system without taking a critical final step — reengaging the yaw servo hydraulic switch after the check. The pilot might have discovered the lack of hydraulic pressure had he performed a hover check just after lift-off.
The EADs required installing certain parts and a warning system. The tail rotor hydraulic system check also must be conducted after rather than before flight. The reasoning was that pilots are more likely to perform the check during shutdown when they don’t feel as rushed. The ADs also required that the yaw servo hydraulic switch be in the ‘’ON’’ position before take-off.
Collectively, pilots should consider the factors that led and contributed to this accident’s fatal outcome and what can be done to reduce accident risks. A crash resistant fuel system provides an additional layer of safety by minimizing the occurrence of a post-crash fire should a survivable accident occur.
We all have issues that distract us. Using checklists for pre- and post-flight inspections is crucial for safe flights. They help us focus on specific safety checks. There’s so much more that this Frisco accident profile and the other lessons learned will teach you. Please read them.
Gene Trainor works as the communications specialist/executive technical editor for the FAA’s Compliance and Airworthiness Division.