The NTSB unanimously agreed on the probable causes of a May 2019 midair collision in Alaska that killed six and injured 10. The board cited obstructed views due to aircraft structure and passengers and the lack of an aural traffic alerts in crowded airspace.
The pilot and four passengers in a de Havilland Beaver floatplane operated by Mountain Air Service died, as well as one passenger in a de Havilland Otter operated by Taquan Air, when they collided at 3,350 feet. The rest of the passengers in the Otter survived along with the pilot. All the passengers on both aircraft were from the same cruise ship and were on noontime sightseeing flights to Misty Fjords National Monument near Ketchikan, where the aircraft were based.
According to the board Vice Chairman Bruce Landsberg, “see and avoid” was not sufficient in the high-traffic sightseeing area where the floatplanes were operating. Board Chairman Robert Sumwalt cited “preoccupation with matters unrelated to [flight] duties such as attempting to provide passengers with a scenic view and physiological limits on the human vision, reducing the time opportunity to see-and-avoid other aircraft.”
The NTSB also noted the Beaver pilot would have had his view obstructed just before the collision by the airplane’s structure as well as the passenger to his right. In addition, a window post would have impeded the Otter pilot from spotting the Beaver in time, according to the board’s findings. The board’s human performance specialist noted that the Otter pilot last recalled looking at his in-cockpit traffic display “about four minutes before the collision.”
The probable-cause finding from the board also cited the lack of an FAA requirement for aural and visual traffic alerts on airplanes carrying passengers.
Pretty much the same as the Coeur D’Alene tragedy.
Moral of these stories : Don’t go on sightseeing flights and if your flying your plane, stay high and have some sort of collision avoidance system.
Would adsb-out helped and is the airspace around the area where the collision occurred covered by adsb?
” is the airspace around the area where the collision occurred covered by adsb?”
If both airplanes had ADS-B out AND in, they’d be able to ‘see’ each other directly. There’s no such thing as “covered by ads-b” as in radar like coverage. Now then, would the pilots have been paying attention to an ads-b in traffic screen … likely not.
The article says that the Otter pilot had not checked his in-cockpit traffic display in about four minutes. ADS-B won’t do you much good if you don’t look at it. The Ketchican weather is notoriously rainy and overcast with low visibility. Unfortunately, when the cruise ships arrive, there is a flood of people who have booked the aerial tours, which puts pressure on the pilots to go regardless of conditions. To preserve a somewhat “sterile” cockpit, a separate tour guide should go along on the flights to communicate with the passengers and leave the flying to the pilot. But, that would take a seat away from a paying customer, so they don’t do it.
Unless something such as a freaking out or suddenly ill passenger creates a distraction, the chore of handling the guest communication & commentary isn’t really much of a load on the pilot. The routes are pretty well “canned”, and in fact I’ve taken tours where the commentary is recorded also.
Considering the sheer volume of sightseeing operations in places like Alaska and Hawaii coupled with the equipment & flight conditions, their overall safety record really seems quite remarkable. Now obviously, if your standard of comparison is scheduled airlines, well….
It’s been known for decades that “see-and-avoid” often doesn’t work. You can’t avoid what you can’t physically see.