<figure class="wp-block-image aligncenter size-full"><figcaption class="wp-element-caption">CG6016 came to rest inverted on the beach on Read Island, after striking the trees and falling approximately 75 feet, during a rescue mission on the night of November 13, 2023. An official MII (Major Incident Investigation) obtained by KCAW concluded that pilot “fixation” and “spatial disorientation” — rather than a mechanical or instrument failure — caused the accident. (USCG photo)</figcaption></figure><figure class="wp-block-audio"></figure>

Note: The Coast Guard MII (Major Incident Investigation) report found no fault with the crew of CG6016 for continuing the mission on November 13, 2023, even though the Lydia Marie was out of immediate danger. Read the story.

Often in Sitka, on the darkest, most dismal, stormy nights, the sound of the wind will seem to grow, and then begin to thrum with mechanical force. That audible shift from the power of nature, to the power of machine means a Jayhawk helicopter is launching from Air Station Sitka, on a medevac, search and rescue, or unbelievably, a training flight.

Practicing dangerous things until they become routine is the Coast Guard’s brand. On the night of November 13, 2023, a Jayhawk took off to assist a fishing boat, the Lydia Marie, which was taking on water in Farragut Bay, 22 miles northwest of Petersburg.

The helicopter, Coast Guard 6016, would not return. Cmdr. Rand Semke was the operations officer of Air Station Sitka at the time, and is now its commanding officer. He is also a pilot. He flew a second helicopter on a mission to locate the first. He says it was one of the most difficult he’s ever flown.

“It was incredibly dark night with high moisture environment,” said Semke, “and you just really cannot see much as you’re flying, even as you’re hovering low over the water.”

Semke found CG6016 inverted on the beach of Read Island. It had struck the trees on shore and plummeted about 75 feet. The crew of the Lydia Marie, which was no longer in danger, had rowed a skiff ashore to aid the helicopter crew, all four of whom were injured, two seriously.

Semke flew the injured to Petersburg for emergency treatment, and they were subsequently medevaced  to Seattle for further care. The following day, the Lydia Marie was escorted back to Petersburg by a Coast Guard cutter.

All of these details were in the news at the time, but one detail was missing: What caused the crash? In the following months, the Coast Guard conducted an Major Incident Investigation (MII) which KCAW has since obtained. The investigator concluded that the crash was the result of “controlled flight into terrain.” There was no mechanical failure, no instrument glitch. There was also no warning. The cockpit audio reveals a crew going about the business of preparing to lower a dewatering pump to a distressed fishing vessel on a windy night with poor visibility. Then they hit the trees, and it’s game over. 

How could a routine mission go so badly? It turns out that nothing about flying rescue helicopters is routine.

“Hovering a helicopter over water at night in bad weather when lives are on the line, is one of the most challenging things you can do in all of aviation,” Semke said.

Semke says that helicopters seem to defy the laws of physics, and that just keeping them airborne is a high workload for pilots. Even on nice days in daylight, when hovering over water, pilots perceive that the entire environment is moving. And then they have to lower a line, a pump, or a human to a moving target.

“The H60T helicopter puts out hurricane-force downdraft underneath of it – the rotor wash, we call it – which tends to move the vessels that you’re trying to deliver rescue devices to,” Semke said. “If a vessel is at anchor, they don’t move in a predictable manner. They’ll swing around their anchor when they’re impacted by the rotor wash. So now we’re putting it all together: We’ve got a helicopter hovering, which is challenging. Now it’s over water, more challenging. Now it’s at night, it’s even more challenging. A high wind environment, lots of precipitation in the air, which degrades your visual references. It was both snowing and raining north of Petersburg that night, and now you’re trying to deliver an item to a crowded deck on the Lydia Marie while they’re at anchor. There aren’t many more challenging situations.”

The investigation revealed that for 69 seconds, the pilots of CG6016 thought they were in one place, but they were actually moving. The helicopter was drifting right, and turning – or yawing – to the left, so the Lydia Marie was always visible over the dashboard.

Semke says having just a single reference point created an illusion broadly called “fixation” which then leads to “spatial disorientation.” The phenomenon comes in many different forms and affects other aircraft besides helicopters. Coast Guard pilots train intensively to avoid it. Semke himself has been flying for 17 years. That night he also experienced spatial disorientation, much as the crew of CG6016 had.

“And when we got on scene, at one point, I was flying and experienced something very similar, based on the the degraded visual environment, the heavy snow squalls, darkness, the somewhat disorienting light of the one fishing boat nearby, and at one point, I myself was drifting towards the island,” he said. “You would think we’d be hypersensitive to this.”

<figure class="wp-block-image aligncenter size-full"><figcaption class="wp-element-caption">The MII (Major Incident Investigation) shows damage to the trees 65-75 feet above where CG6016 came to rest on the shore of Read Island. (USCG image)</figcaption></figure>

The remedy is teamwork, and trust in the aircraft’s instruments. We’ve all been relieved when flying commercially in Southeast Alaska when the jet drops out of the clouds and the runway lights are right there.  For Coast Guard aviators on a rescue, there are no runway lights, nothing to see, even with night-vision goggles.

“We do have instrumentation that tells us if we’re drifting in a hover, our altitude in a hover,” said Semke. “But most of helicopter hovering is visual reference to the outside environment. So if you’re hovering next to something, you can maintain your relative position next to something, and you know that you’re not moving. Well when one of your primary references is a boat at anchor in a high wind environment, it’s moving. So if that’s your sole reference, then you’re going to be moving too, and you might not even realize it.”

The Major Incident Investigation (MII) doesn’t pronounce judgment on the crew of CG6016. In fact, as far as training hours and certifications go, everyone aboard was at the top of their game. To even become a rookie aviator in Alaska you have to be experienced elsewhere. No one died in this incident, thankfully, but that did not put every question to rest. Cmdr. Semke says the Coast Guard is invested in the nuanced human factors that contributed to the accident, and making corrections. “That is how we must operate,” he says, “even as technology is always seeking to take the human out of the equation.”

Note: An earlier version of this story misidentified Rand Semke’s position at Air Station Sitka in November of 2023. He was the Operations Officer, not the Executive Officer.

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