A US Air Force civilian contractor was killed when she walked into a drone’s rotating propeller at a California airfield — after losing “situational awareness” while glued to a data-recording device, officials say.
Stephanie Cosme, 32, was fatally injured when she “inadvertently” stumbled into the moving propeller of a parked MQ-9A Reaper drone at Gray Butte Airfield on Sept. 7, according to a new statement from Air Force Materiel Command summing up the findings of a report on the accident.
“Without looking up to determine her position relative to the aircraft, [Cosme] proceeded to walk directly into the propeller of the [aircraft] sustaining fatal injuries,” stated the final investigation report released Friday.
In his statement of opinion, Accident Investigation Board President Brig. Gen. Lance French identified two causes for the accident.
First, Cosme was incorrectly instructed or trained on how to take data readings when approaching a drone while its engine is running.
Second, “she lost situational awareness” while walking around the unmanned aircraft taking readings with a hand-held measurement device, the report stated.
French also singled out two additional factors he said “substantially contributed to the mishap,” including a clear lack of communication between the contractor test team and ground support workers and the fact that the tests conducted on Sept. 7 were “rushed” because of previous delays.
Cosme, who was employed by the company Sumaria Systems, LLC, which provides test support services for the Air Force, took measurements with a power meter and then proceeded to walk toward the rear of the drone, “looking down at the testing device the whole time.
She also “appeared to be pressing buttons, possibly to keep the backlight on,” the report said, describing how she was “focused in on that meter.”
As Cosme inched closer to the whirring propeller, her co-workers began “shouting and waving” to draw her attention, to no avail.
After the impact, the crew chief was heard yelling over the radio, “Kill, kill, kill kill!” before one of the workers was seen on the drone’s front camera running from right to left, presumably toward the Reaper’s kill switch.
Cosme was found bleeding from wounds to her head and left arm and was unresponsive but still breathing. She was airlifted by a helicopter to a hospital but died a little over an hour later.
As part of the probe into the accident, Air force officials tried to replicate the sequence of events at the same location, with a Reaper drone’s engine running at the same power settings, in the same twilight lighting conditions and under the stadium lighting that as present Sept. 7.
The re-enactment led to the conclusion that the spinning propeller was not visible from Cosme’s viewpoint, and she most likely never heard anyone shouting warnings over the roar of the engine.
Cosme of Palmdale, Calif., was described in an obituary as “a cherished daughter, sister, fiancé, mother, and friend” who “touched the hearts of everyone she encountered with her warmth, kindness, and unwavering love.”
“She was known for her passion for crafting, baking, aviation, and all things strange and unusual,” the obituary continued.
The woman was survived by her parents, two siblings, fiancé and stepdaughter.