The National Transportation Safety Board (NTSB) announced this week that a lack of night-flying experience and spatial disorientation is what led to a deadly July 4, 2016, plane crash in the Pacific Ocean about 2 miles off Rainbow Rock north of Brookings.

Killed in the incident was the pilot, 46-year-old John Belnap, his son, Max, and the youth’s friend Ryan Merker, both 17. All were from Grants Pass.

Rough ocean conditions prevented rescuers from finding all the bodies for 30 days, although divers took to the water whenever the weather allowed.

Belnap and the two youth flew here from Hollister, California, to partake in Fourth of July weekend festivities with friends and family. They tried to make the return trip home at about 10:30 p.m. July 4, but crashed into the ocean. The flight typically takes 35 to 45 minutes.

It took search teams from counties as far away as Clackamas 19 days of scouring the coastline before they found the first body, pinned under a wing of the plane. The second was found the following day about 30 feet from the wreckage in visibility so poor divers reported not being able to see 2 feet in front of them.

Airplanes, helicopters, U.S. Coast Guard vessels and an Idaho volunteer with a sonar-equipped boat were all enlisted in the search.

Some pilots interviewed correctly believed Belnap could have become disoriented in the moonless night, and might not have had the experience with instrument-panel flying needed to negotiate the dark terrain between the two cities.

According to the report, Belnap held a private pilot certificate with an airplane, single-engine land rating. He did not hold an instrument rating. According to his logbook, Belnap had accumulated 207 total flight hours, all of which were in that airplane.

The last entry recorded in the logbook was on March 7, 2016, for a cross-country trip; that trip took 13.8 flight hours of which three were at night. No other night-flight time was recorded in the six months prior to the accident.

A salvage company retrieved parts of the Cessna 172F, which was broken into numerous pieces on the ocean floor. The main body of the plane was never recovered.

The NTSB said in its report that the three were headed west after leaving the Brookings Airport, and reached a maximum altitude of about 700 feet.

“A witness heard an airplane flying nearby and assumed that it was taking off from the airport,” the report reads. “As the airplane continued, he heard a reduction in engine power, like a pilot throttling back while landing.”

When the three didn’t arrive home, a search was started.

The report indicated there was no natural horizon and few visual references due to the darkness at that hour. That would have required the pilot to monitor the flight instruments to maintain awareness of the airplane’s altitude.

“Given the lack of external visual cues and the the pilot’s lack of recent night flight experience and his lack of an instrument rating, it is likely he became spatially disoriented during the departing left turn.”

The main wreckage was not recovered, the NTSB said, so investigators could not determine if mechanical malfunctions or anomalies were to blame.

Belnap was a nurse anesthetist for Asante, working at Three Rivers Medical Center, and belonged to a search and rescue group — some of whom were looking for him. His son was a top runner on the Grants Pass High School cross-country and track teams, and Merker had recently won the pole vault event at the district meet.

“Night flying is very different from day flying and demands more attention of the pilot,” the report concluded. “Generally, at night it is difficult to see clouds and … a pilot flying under visual flight rules (VFR) must exercise caution to avoid flying into clouds or a layer of fog.”

Additionally, motion-sensing in the inner ear particularly tends to confuse a pilot who cannot see, the report reads.

“Because of inertia, the sensory areas of the inner ear cannot detect slight changes in the attitude of the airplane, nor can they accurately sense attitude changes that occur at a uniform rate over a period of time,” it said. “On the other hand, false sensations are often generated, leading the pilot to believe the attitude of the airplane has changed when in fact, it has not. These false sensations result in the pilot experiencing spatial disorientation.”

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