NBAA’s Safety Committee recently issued its annual update to its list of major safety concerns. One area of the committee’s 2021/2022 focus is preventable accidents, which the committee has broken down into three primary categories: loss of control in flight (LOCI), runway excursions (RE), and controlled flight into terrain (CFIT). Searching through NTSB records, AIN chose these accidents as representative of those categories:
Loss of control in flight: On July 26, 2021, the crew of a Bombardier Challenger 605 lost control while conducting a midday circling approach to Runway 11 at California's Truckee Tahoe Airport (KTRK) following the RNAV GPS Runway 20 approach. The Challenger caught fire on impact, claiming the lives of its two pilots and four passengers. Skies at Truckee were mostly clear, but visibility was just four miles. Westerly winds prevailed at 11 knots with gusts to 16. Although the aircraft operator held a Part 135 certificate, this flight was flown under Part 91.
Early in the arrival sequence, the crew requested and received permission from Oakland Center to circle to Runway 11 despite a possible tailwind component and a southeasterly downslope on the runway. As the aircraft passed the LUMMO waypoint about 10 miles north of KTRK, the tower controller offered the crew the option of crossing over the field and entering a left downwind for Runway 29 or continuing to Runway 11.
The crew stuck with their original choice of Runway 11 and reported that it was in sight. A tower controller cleared the flight to land on Runway 11, noting that ATC did not have the jet in sight. The flight crew’s acknowledgment of the clearance was their final radio communication. ADS-B flight path data showed that the Challenger overshot the Runway 11 centerline at low altitude and appeared to be trying to correct back at the time of the crash.
One eyewitness recalled noticing the aircraft's low altitude and abnormal flight path. Another said the airplane was in a nose-down attitude and steep left turn during its final few seconds of flight, while a third—located about 50 feet from the accident site—reported that it came from the northwest, about 20 feet above the trees, and appeared to be intact. The airplane entered a steep left turn and banked erratically before it impacted trees and then the ground. Three surveillance videos captured the flight’s final movements and were all consistent with the witnesses’ accounts.
The NTSB said the initial point of impact was with a tree that stood about 70 feet high and was about 120 feet west of the main wreckage. Portions of the right and left wings and control surfaces were found fragmented along the debris path. Additional airframe fragments were collocated with the main wreckage, which consisted of both engines, the empennage, and fuselage remnants.
Runway excursion: The Aug. 19, 2019, mid-afternoon crash of a Cessna Citation Latitude some 600 feet past the end of Runway 24 at Elizabethton (Tennessee) Municipal Airport (K0A9) following a highly unstabilized VFR arrival. That arrival became noteworthy as the jet crossed a ridgeline northeast of the field at an altitude low enough to trigger a terrain warning.
On approach, both pilots commented that the aircraft was traveling much too fast at the time. Approximately two minutes before touchdown, the pilot pulled the throttles to idle, where they remained for the rest of the arrival.
“In an attempt to slow the airplane for landing, the pilot partially extended the speed brakes when the airplane was below 500 feet agl, which is prohibited in the airplane flight manual (AFM)," the NTSB said in an accident report. "Five seconds before touchdown, the airplane's descent rate was 1,500 feet per minute (fpm), which exceeded the maximum allowed for landing per the AFM of 600 fpm.”
Additionally, the aircraft was approaching some 18 knots faster than the calculated Vref speed. The result was that the jet bounced four times on the runway before it finally left the paved surface.
At touchdown, the pilot did not extend the speed brakes as recommended but instead attempted to deploy thrust reversers. The reversers did not deploy because the aircraft was in mid-bounce and the command could not be executed due to the system’s logic.
These bounces and the pilot’s attempt to first open, then stow, the reversers created a system oscillation of sorts that left the engines unable to accelerate with the reversers still open. During the fourth bounce, the right main landing gear collapsed, and the aircraft left the pavement, finally stopping 600 feet past the runway threshold. The passengers and crew evacuated safely, but a post-crash fire destroyed the Latitude.
Controlled flight into terrain: Details are still being gathered about the Aug. 5, 2021, crash of a DHC-2 Beaver Mark 1 floatplane into a mountain near the Misty Fjords National Monument some 10 miles northeast of Ketchikan, Alaska. The flight was being operated as a VFR sightseeing tour for passengers of the Holland America Line cruise ship Nieuw Amsterdam, which was docked at Ketchikan, where the flight was scheduled to end.
The accident occurred just before midday and destroyed the Beaver while also claiming the lives of the five cruise ship passengers and one pilot aboard. A U.S. Coast Guard MH-60 Jayhawk crew that located the wreckage reported weather at the site as light rain and mist with moderate winds and two-mile visibility.
Alaska Public Media (APM) said that 21 people have perished in sightseeing tour accidents in the Ketchikan area since 2015. APM noted that the NTSB determined the probable cause of a 2015 tour accident that killed nine people to be the pilot’s decision to continue the flight in the face of deteriorating weather. In 2017, the NTSB asked the FAA to create more conservative rules for the Ketchikan air tour industry.
The board has since launched the Alaska Aviation Safety Initiative to determine what more can be done. Because the NTSB is just beginning its investigation into the July 5 accident, details of the Beaver pilot’s experience have not yet been made public.